ethnic identifiability: an experimental...

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Ethnic Identifiability: An Experimental Approach* James Habyarimana Georgetown University Daniel N. Posner University of California, Los Angeles Macartan Humphreys Columbia University Jeremy M. Weinstein Stanford University Abstract We report the results of an experimental project that investigates the determinants of ethnic identifiability – that is, how well individuals can correctly categorize the ethnic backgrounds of the people they encounter. Drawing on a subject pool of ninety-six university students from seven different ethnic groups, we find ethnic identifiability to be more difficult than is often assumed. We find that three factors determine the ability of subjects to identify the backgrounds of others: the characteristics of the person being identified (in particular, his or her ethnic group membership), the characteristics of the identifier (in particular, the extent of his or her exposure to other ethnic communities), and the level of information that the latter has about the former. We also investigate the ability of individuals to “pass” as members of other groups, and to identify “passers.” We find that “passers” are able to fool others roughly 45 percent of the time. Determinants of successful passing include the passer’s ethnic group membership, age, and SAT score. Our findings challenge micro-level theories of ethnic politics that assume that individuals can readily distinguish in-group members from out-group members. *The authors thank Chris Crabbe for his superb programming work; Dan Young, Donna Horowitz, and Kevin Thelen for their research assistance; the Russell Sage Foundation, the Harry Frank Guggenheim Foundation, the Harvard Academy for International and Area Studies, and the International Institute at UCLA for their financial support; and the staffs of the California Social Science Experimental Laboratory (CASSEL) at UCLA and the Center for International Studies and the Law School Library at USC. Extremely helpful comments were received from participants at the 9 th meeting of the Laboratory in Comparative Ethnic Processes (LiCEP), University of Wisconsin, 7-8 May 2004. Protocols for the experiment are available on request from the authors.

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Page 1: Ethnic Identifiability: An Experimental Approach*web.mit.edu/posner/www/papers/ethnic_identifiability.pdf · groups more readily identifiable – for example, the requirement that

Ethnic Identifiability: An Experimental Approach*

James Habyarimana Georgetown University

Daniel N. Posner

University of California, Los Angeles

Macartan Humphreys Columbia University

Jeremy M. Weinstein Stanford University

Abstract

We report the results of an experimental project that investigates the determinants of ethnic identifiability – that is, how well individuals can correctly categorize the ethnic backgrounds of the people they encounter. Drawing on a subject pool of ninety-six university students from seven different ethnic groups, we find ethnic identifiability to be more difficult than is often assumed. We find that three factors determine the ability of subjects to identify the backgrounds of others: the characteristics of the person being identified (in particular, his or her ethnic group membership), the characteristics of the identifier (in particular, the extent of his or her exposure to other ethnic communities), and the level of information that the latter has about the former. We also investigate the ability of individuals to “pass” as members of other groups, and to identify “passers.” We find that “passers” are able to fool others roughly 45 percent of the time. Determinants of successful passing include the passer’s ethnic group membership, age, and SAT score. Our findings challenge micro-level theories of ethnic politics that assume that individuals can readily distinguish in-group members from out-group members. *The authors thank Chris Crabbe for his superb programming work; Dan Young, Donna Horowitz, and Kevin Thelen for their research assistance; the Russell Sage Foundation, the Harry Frank Guggenheim Foundation, the Harvard Academy for International and Area Studies, and the International Institute at UCLA for their financial support; and the staffs of the California Social Science Experimental Laboratory (CASSEL) at UCLA and the Center for International Studies and the Law School Library at USC. Extremely helpful comments were received from participants at the 9th meeting of the Laboratory in Comparative Ethnic Processes (LiCEP), University of Wisconsin, 7-8 May 2004. Protocols for the experiment are available on request from the authors.

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Micro-level theories of ethnic politics nearly all depend on strong assumptions about the

ability of individuals to identify the ethnic backgrounds of the people with whom they interact.

Although a great deal of anecdotal evidence calls such assumptions into question, no systematic

research to date has attempted to assess how well individuals can distinguish in-group members

from out-group members or sort out-group members into their correct ethnic categories. This

paper reports the findings of an experimental project designed to fill this gap in knowledge.

Drawing on a sample of ninety-six undergraduate students from seven different ethnic groups,

we explore the determinants of what we term “ethnic identifiability.” Specifically, we test

whether subjects are able to classify the people whose images they are shown into the ethnic

categories with which the people themselves identify. We test how the characteristics of the

person viewing the images, the characteristics of the person whose images are viewed, and the

degree of information that the former has about the latter affect the probability of a correct ethnic

identification.1

We find that subjects are less able to distinguish in-group members from out-group

members and less able to sort non-co-ethnics into their correct ethnic categories than most

theories of ethnic politics assume. When shown pictures of other subjects, subjects miscoded in-

group members as out-group members 16 percent of the time and miscoded out-group members

as in-group members 7 percent of the time. Subjects were even less successful at identifying the

ethnic backgrounds of people from other ethnic groups. On average, subjects shown images of

1 By “correct identification,” we mean a match between the ethnic identity ascribed to the person by the

subject and the person’s own self-identification. For a more technical definition of “ethnic

identifiability,” see below.

1

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people from other ethnic groups miscoded the other person’s ethnic background 33 percent of the

time.

Asking students to come to a computer laboratory, look at images of other students on a

computer screen, and guess those students’ ethnic backgrounds is, admittedly, quite far removed

from the real world situations that theories of ethnic politics endeavor to capture. Particularly in

situations where the costs of ethnic misidentification are high, actors will have incentives to

collect additional information about the person whose background they are trying to identify, and

such information will go well beyond the cues available to students viewing other students’

images on a computer screen in a laboratory setting. Moreover, precisely in situations where

actors will have incentives to figure out other people’s ethnic backgrounds, the people being

identified are likely to have equally strong incentives either to hide their true identities or to

make their identities more apparent.

To better capture such real world situations, and to improve the external validity of our

experiment, we also test the ability of subjects to simulate and dissimulate – that is, to convince

others of their true ethnic backgrounds and to pass as members of ethnic groups other than their

own. We find that the rate of correct ethnic identification rises from a baseline average of 71

percent (when subjects are shown pictures of other subjects) to 89 percent when they are shown

brief videos in which the other subjects try to convince them of his or her true ethnic identity.

The identification rate drops to 55 percent when subjects are shown videos of other subjects

trying to pass. The implication is that when individuals want either to convince others of their

ethnic group membership or (contra the assumptions of many models of ethnic politics) fool

them about their ethnic background, many of them are quite able to do so.

2

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THE ASSUMPTION OF UNPROBLEMATIC ETHNIC IDENTIFICATION AND EVIDENCE FOR ITS IMPLAUSIBILITY

The assumption that individuals can seamlessly identify the ethnic backgrounds of the

people they encounter – or, at the very least, unproblematically distinguish in-group members

from out-group members – is implicit in nearly all micro-level theories of ethnic interaction and

politics. From theories of in-group sanctioning (Greif 1989; Landa 1994; Fearon and Laitin

1996) to theories that emphasize the ability of ethnic groups to police their boundaries (Barth

1969; Laitin 1995; Fearon 1999; Caselli and Coleman 2002) to theories of ethnic or racial

discrimination (Akerlof 1970, 1976; Becker 1971) to experimental treatments of minimal groups

(Tajfel, Billig, and Bundy 1971), models of face-to-face ethnic interaction almost always depend

on the ability of actors to distinguish accurately between in-group members and outsiders. For

in-group sanctioning to work, the group memberships of transgressors must be clear.2 For ethnic

boundaries to be policed, the line between insiders and outsiders must be unambiguous.3 For

discrimination to be possible, peoples’ group backgrounds must be easily identified. In all of

these cases, identification failure undermines the predictions of the model.4

2 For example, Fearon and Laitin’s in-group policing model explicitly stipulates that actors know when

they are interacting with in-group members versus outsiders (1996: 721).

3 Caselli and Coleman (2002), whose model emphasizes the policing of boundaries, make an important

theoretical advance by permitting actors in their model to take costly actions to change their identities.

But they maintain the position that, once changed, an actor’s identity will be self-evident to the other

players in the game.

4 Quite apart from the role it plays in theories of ethnic competition and conflict, the easy identifiability of

ethnic groups is also one of the underlying assumptions in many accounts of ethnicity itself. Chandra

(2004), for example, argues that identifiability is one of the characteristics that sets ethnic groups apart

3

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The strong implicit or explicit claim in these models that individuals can

unproblematically distinguish in-group members from outsiders flies in the face of evidence that

people’s ethnic backgrounds are sometimes extremely difficult to pin down. Despite widespread

assumptions to the contrary, people are often not very good – and often not as good as they

themselves believe – at classifying others in ethnic terms. The case study literature on ethnic

riots and communal conflict is filled with anecdotes illustrating this point. For example,

Horowitz relates the following story from Sri Lanka:

Sinhalese rioters suspected a man in a car of being a Tamil. Having stopped the

car, they inquired about his peculiar accent in Sinhala, which he explained by his

lengthy stay in England and his marriage to an English woman. Uncertain, but

able to prevent his escape, the rioters went off to kill other Tamils, returning later

to question the prospective victim further. Eventually, he was allowed to proceed

on his way, even though the mob knew it risked making a mistake, which in fact it

had: the man was a Tamil (2001: 130).

The eyewitness account of witness to a 1997 massacre by Hutu rebels in Buta, in southern

Burundi, offers a similar illustration:

There were 250 children, ages 11 to 19. On April 30, around 5:30, we heard

shots. In several minutes, the assailing rebels had become masters of the

seminary. The soldiers charged with protecting us had fled. A troop of rebels had

taken over the dormitories…The assailants gathered us in the middle of the room

from non-ethnic groups, and that this is one reason why ethnicity so frequently plays a role in situations

where information about other actors’ preferences, trustworthiness, and political orientation is limited

and/or costly to obtain.

4

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and demanded that we separate into Hutus and Tutsi. The students refused. They

were united. Then the leader of the group, an enraged woman, ordered their

killing. There were 70 students. The assailants fired their grenades (National

Catholic Reporter, 22 February 2002).

In both of these examples, the attackers had difficulty coding the ethnic backgrounds of their

would-be victims. Similar uncertainty has marked the estimated two thousand backlash

incidents directed at Muslims and people of Arab descent in the aftermath of the September 11

terrorist attacks in the United States. More often than not, the victims of these hate crimes turned

out not to be Muslims or Arabs at all, but Sikhs, Indians, Pakistanis, Coptic Christians, and, in

one case, even an Iranian Jew (Human Rights Watch 2002).5 These examples starkly illustrate

that ethnic categorization is not nearly as straightforward as theories of ethnic conflict often

assume.6

Apart from challenging theories that assume that ascertaining a person’s ethnic

background is unproblematic, entertaining the possibility that people’s ethnic backgrounds might

not always be readily identifiable also opens the door to new hypotheses about the conditions

5 We cannot rule out the possibility that the perpetrators of these anti-Muslim acts simply did not know

that the Sikhs, Indians, and Pakistanis, and the others they attacked were not Arab Muslims, in which case

the miscodings would not be examples of ethnic misidentification as we treat it in this paper but simply of

not being aware that there were different categories into which the would-be victims might be coded.

6 The great lengths to which governments have historically gone to make members of particular ethnic

groups more readily identifiable – for example, the requirement that Jews wear the Star of David, that

Japanese-Americans wear markers indicating their Japanese descent, or that citizens carry national

identity cards with information about their ethnic or racial background (as is still the case in Israel,

Singapore, and Vietnam) – further underscores the difficulty that ethnic identification often presents.

5

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under which existing theories might and might not hold. Take, for example, the proposition that

ethnic identifiability varies across groups – a proposition for which our study provides strong

evidence. To the extent that this is the case, theorists of ethnic coalition building can use

identifiability as a determinant of coalition choice. Theorists of in-group policing can use it to

distinguish among communities with greater and lesser abilities to sanction their members, and

thus greater or lesser abilities to execute certain business transactions, organize collectively, or

prevent inter-group conflicts from degenerating into spirals of violence (Fearon and Laitin 1996).

Theorists of ethnic mobilization can use it to account for variation in the ease with which

political entrepreneurs may be able to organize – or organize against – particular communities.

Theorists of ethnic violence can use it to explain the form that conflict takes.

Regarding the latter, consider the wars in the north of Mali (1990-1995) and the south of

Senegal (1982-present). The two conflicts would seem to have much in common. Both involve

bids for separation by movements dominated by members of minority groups: the Tuaregs and

Maures in Mali and the Diola in the Casamance region of Senegal. However, differences in the

identifiability of the parties to each conflict have generated important differences in how group

members are mobilized and how violence is carried out. In Mali, the fact that the Tuaregs and

Maures – the “whites” – are readily identifiable has meant that ethnicity can be used to pressure

members of these groups, including intellectuals living in the capital, to join the rebel

movements. It has also allowed “black” sedentary groups and the Malian army to take reprisals

against arbitrary Tuareg and Maure civilians. The result has been a rapid polarization of camps

and the descent of the separatist struggle into communal violence. In Senegal, by contrast, such

ready association of individuals with ethnic groups has been more difficult. As a consequence,

the mobilization of partisans and the targeting of reprisals has been more difficult, and the

6

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intensity of violence has been much lower (Humphreys and ag Mohamed 2002). The contrasting

degree of ethnic identifiability has led to a sharp difference in the form of group mobilization and

the scope of violence in each case – a difference that would be hard to account for if we assumed

erroneously that all ethnic groups were equally identifiable.

As the foregoing discussion suggests, a finding that ethnic identifiability cannot be taken

for granted has important implications both for existing theories and for the development of new

ones. But how great is the distance between the assumption of unproblematic identifiability and

the reality? Anecdotes about the difficulty people sometimes have in pinning down the ethnic

backgrounds of others are suggestive, but what can be said systematically? How well, in fact,

can individuals sort the people they encounter into their correct ethnic categories? What factors

facilitate or impede their ability to do this? Are the members of some ethnic groups more easily

identified than others? What makes some people better identifiers than others? The experiments

we reported in this paper were designed to answer these questions.

RELATION TO PREVIOUS RESEARCH

Social psychologists have made important contributions to our understanding of how

individuals classify others into ethnic categories. The core of this body of research has been on

the relationship between prejudice and patterns of social categorization, a somewhat different

question from the one addressed in this paper. Nonetheless, these studies provide an important

methodological foundation for our experiment and are therefore worth reviewing.

In terms of experimental design, four major studies capture the evolution of approaches

to assessing how individuals categorize others into ethnic groups. Allport and Kramer (1946)

initiated this line of research with a study that asked a sample of university students to

7

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distinguish pictures of Jewish students from pictures of non-Jewish students. Participants were

given fifteen seconds to view each photograph before being asked to identify the person as

“Jewish,” “Non-Jewish,” or “Don’t Know.” Pettigrew, Allport, and Barnett (1958) improved on

this rudimentary design by introducing a stereoscope – a device that presents different images to

the left and right eye so that participants see a single merged object. The stereoscope enabled

Pettigrew and his colleagues to examine how individuals classify images that combine persons

from two different groups.

More recent research in this area has employed computer and video technologies to

explore the same questions. Blasovich, Wyer, Swart, and Kibler (1997) showed photos of white,

black, and ambiguous individuals to participants and measured the amount of time it took them

to identify the race of the person in the photo. Harris (2002) used a web-based survey of

university students in which participants were asked to categorize a set of photographs as white,

African-American, Latino, Asian-American, American Indian, Pacific Islander, or other. He

analyzed both the classifications the students made and their response times.

What determines identification success? The literature identifies a number of individual

and group-level factors that are associated with successful ethnic categorization. Early work

emphasized the role played by prejudice, as measured through questions about the subject’s

awareness of and opinion about members of other ethnic groups (e.g., Allport and Kramer 1946).

Secord (1959) introduced information into the experimental design, varying the directions given

to participants about their task. While some participants were told nothing about the race of the

people in the photographs, others were told that they all had “Negro” blood, no matter how white

they looked. Lent (1970) proposed that future studies introduce a new range of participant

characteristics including broader demographic variables, a subjective measure of the perceived

8

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situation of one’s racial group, a subjective measure of the relation of one to one’s group, and

objective measures of the relative position of each racial group in society. Most recently, Harris

(2002) focused on the impact of observer race, gender, and experience with other races on

identification choices. He found that whites and Asian-Americans more quickly classified

photographs and used many fewer racial groups to categorize the full set of photographs, while

other minority groups were more likely to see complexity in the photographs. Harris also

identified a strong relationship between a participant’s experience with other races and how he or

she classified the images.7

The experiment reported in this paper, while closest to Harris (2002), nonetheless goes

beyond this work in three important ways. First, the study involves a larger number of ethnic

groups than any other study to date. The early literature tended to focus narrowly on racial

categorization between blacks and whites or religious categorization between Jews and non-

Jews. Our study involves participants from seven different ethnic groups, encompassing a much

greater degree of phenotypical variation than in previous work.

Second, we go beyond Secord’s (1959) pioneering work in testing the effects of

information on ethnic identification. Participants in the experiment are exposed to three different

images of each subject, each providing a different level of information about the subject’s ethnic

background. First, they are shown a still photograph of the subject – a headshot – from which

7 The effects of ethnic group membership have also begun to be explored by experimental economists

(e.g., Fershtman and Gneezy 2001; Gil-White 2004; Ferraro and Cummings 2004). Yet in these studies

the emphasis is on the effects of ethnicity on behavior in experimental games rather than on the

identifiability of subjects. In fact, in all of these experiments, the identifiabilty of subjects as members of

particular ethnic groups is simply assumed.

9

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they can glean clues about the subject’s background from his or her appearance. Then they are

shown a brief video of the subject greeting them. This provides information about accent and

speech patterns, and thus further clues about the subject’s ethnic background. Finally they are

shown a brief video of the subject greeting them and saying his or her full name.8 By exposing

participants, in turn, to each of these levels of information, and asking them to guess the

subject’s ethnic background after each one, we are able to test the impact of information on

ethnic identification.

Finally, in addition to measuring the ability of individuals to identify the ethnic

backgrounds of others, we also explicitly test the ability of subjects to “pass.” In a world of

unproblematic ethnic identification, passing would not be an issue: it would be impossible. But

in a world where a person’s ethnic background cannot be determined with certainty without a

tremendous investment in information about the person’s family history, individuals will

sometimes have incentives to take advantage of the uncertainty of others to try to pass as

members of groups that will provide them with prestige, access, protection, or other benefits. As

noted earlier, this will particularly be the case in politically charged environments where the

costs of ethnic exposure are high. We test the ability of subjects to pass (and the ability of others

to catch them in their attempts) by recording video clips of subjects trying to convince people

that they are members of ethnic communities other than their own. We then show these videos

to other participants and ask them to guess the subject’s ethnic background.

8 A person’s name provides extremely important information about the subject’s ethnic group

membership (Isaacs 1975). Indeed, in Fershtman and Gneezy’s (2001) experimental study of

discrimination in Israel and Posner’s (forthcoming) analysis of ethnic voting in Zambia, names are

employed as the sole marker of ethnic group affiliation.

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DEFINING IDENTIFIABILITY

Before describing our experimental design, it will be useful to define formally what we

mean by ethnic identifiability. We define “successful” identification as a function of both the

characteristics of the identifier and the characteristics of the person being identified. Hence, for

individual A, individual B, and some information set I, we say that B’s identifiability for A, given

I, is given by the expected ability of A to place B in s, where s is one of a set of categories

{s1,s2,…sm}in an identity structure S, conditional upon criterion C, with the property that

criterion C places each element of the population into one and only one category.9 A group’s

identifiability, conditional upon an identity structure S and information set I, is measured by

taking the average across the individuals of that group of the average identifiability of each

individual within that group across the whole population. Thus, a group within structure S is

more identifiable than another if a typical member of that group is more likely to be placed into

their correct ethnic category by a typical member of the population.

EXPERIMENTAL DESIGN

The objective of the experiment was to determine whether participants could identify the

ethnic backgrounds of other participants when shown pictures and brief video clips of them. To

9 More formally, if gA(B |S,I) is A’s guess of the identity of B given structure S and information I, B’s

identifiability for A, (XBA | S,I), is defined as, (XBB | S,I)=Prob(gA(B |S,I)=s). We recognize that, in some

contexts, individuals may belong to multiple categories within any one identity structure, S. This is the

case for people who identify as mixed-race in the United States. For the purposes of simplicity, however,

we begin by assuming that individuals belong to only one category.

11

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distinguish between participants whose images were being shown and participants who were

viewing these images – each participant in the experiment played both roles – we refer to

participants playing the first role as “subjects” and those playing the second role as

“respondents.”

The participants in the experiment consisted of undergraduate students from the

University of California, Los Angeles (UCLA) and the University of Southern California (USC).

The participants were recruited from seven ethnic groups that have large presences on both

campuses: African Americans, Arabs, Asians, Caucasians, Indians, Persian/Iranians, and

Latino/as. Approximately 54 percent of the participants were recruited through ethnic student

associations on each campus. The other 46 percent were recruited from the regular subject

population of the California Social Science Experimental Lab (CASSEL) at UCLA. In neither

recruitment mechanism did we identify participants by evaluating their appearance. In the case

of those recruited through the student associations, we took membership in the association to

indicate membership in the ethnic group – an assumption we later confirmed with a question

about subjects’ ethnic backgrounds in an initial questionnaire. In the case of the students

recruited through the CASSEL subject pool, we determined group memberships through the

responses given in a screening questionnaire.10 We can thus rule out the possibility that our

10 We approached students who had signed up for other experiments at CASSEL and asked them to fill

out a short screening survey that contained a question about their ethnic background. We then contacted

students from our target groups and invited them to participate in the experiment.

12

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recruiting methods might have biased our sample in favor of individuals who were particularly

“identifiable” as members of their respective groups.11

Before the experiment began, we collected three different images of each subject with a

digital camera. Each image was designed to provide more information about the participant’s

ethnic background than the previous one. First we recorded a headshot. Then we recorded a

brief video clip in which the participant greeted the camera and said “Hello, I am looking

forward to playing the game with you.”12 Then we recorded another brief video clip in which the

participant again greeted the camera, but this time also gave his or her full name (e.g., “Hello, I

am looking forward to playing the game with you. My name is John Doe.”). All three images

were filmed in front of an identical blue background. Participants also filled out a brief

questionnaire in which we collected information about their age, gender, ethnic background,

place of birth, parents’ educational background, exposure to various media, and SAT scores.

We also randomly drew a sub-sample of our participants and invited them to record three

additional videos in which they explicitly stated their ethnic backgrounds.13 For the first two

videos, we asked them to pretend that they were in a situation in which it was important that they

convince the person would view the video of their true ethnic background. By “true ethnic

11 We should note that we cannot rule out the possibility that members of campus ethnic associations

might be more “typically” Latino, Asian, Arab, and so forth in their appearances than members of the

broader student population. However, we think this is unlikely.

12 The subjects said that they were “looking forward to playing the game” because these images were also

used in a series of experimental games in which players saw pictures of their partners before playing each

round (see Habyarimana et al. 2004).

13 We invited thirty-six participants to record the additional images, of whom thirty-two accepted our

invitation and had their images recorded.

13

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background” we explained that we meant the ethnic background that the participant used to

identify him or herself. We filmed two versions of this “simulation” video. In one, we asked the

participant to pretend that the person who would see the video was a co-ethnic. In the other, we

asked the participant to pretend that the person who would view the video was a non-co-ethnic.

Finally, we asked the participants to pretend that they were in a situation in which it was

important that they convince the person who would view the video that they belonged to an

ethnic group different from their own. That is, we asked them to try to “pass.” We asked them

to choose an ethnic group (other than their own) from a list of the seven groups included in the

experiment, and we filmed a “dissimulation” video in which the subject attempted to pass as a

member of that group. The instructions for this exercise are reproduced in Appendix A.

After we had collected the images of all subjects, we contacted all the participants by

email to invite them to visit our project web site to sign up for the experiment. Although 120

subjects had their images recorded, only 96 participated in the experiment. The experiment took

place at CASSEL at UCLA and at a computer classroom in the Law School library at USC.

When participants arrived at the lab/computer classroom they were given a card assigning them

to a computer and instructed to put on a pair of headphones that we provided.

Respondents were then shown a series of still images and videos of twenty-three subjects

and asked to guess each subject’s ethnic background.14 Respondents were told that they would

be paid 20 cents for each correct guess. They were also told that

14 The fact that all respondents had previously had their images recorded, and knew that their images

would later be shown to other participants, increases our confidence that respondents believed that the

subjects whose images they were being shown were real. Also, because respondents were not playing an

14

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in some of the video clips you will see, the person will actually tell you what their

ethnic background is. Recognizing that it is sometimes advantageous for people

to try to “pass” as members of groups other than their own, it is possible that

some of the people may be lying about their ethnic backgrounds. You should

keep this in mind when you guess the backgrounds of the people whose images

you see. To earn the most money from this game, you will have to use your

judgment to figure out when people are telling the truth, and when they might be

giving you false information.

Respondents were first shown a headshot of each subject and asked if they knew the

person. Since roughly half of the respondent-subject pairings were between participants from the

same university, it was possible that respondents might know the subjects with whom they were

matched. If this was the case, then the respondent might have had information about the

subject’s ethnic background that went beyond the information provided within the context of the

experiment. The “do you know this person?” question was included to guard against this

possibility. If a respondent indicated that he or she knew the subject, then the subject’s

photograph was replaced with that of another subject.

Once the respondent indicated that he or she did not know the subject, the respondent was

asked to indicate his or her best guess of the subject’s ethnic background from a list of the seven

groups participating in the experiment. Respondents were also asked to indicate their certainty

about their guess on a four-point scale ranging from “a random guess” to “most certain.” We

also measured the respondent’s certainty in a second way, by recording the response time

interactive game with the subjects, it was less crucial than in most experiments that they believed their

partners were real.

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between the moment the headshot appeared (or the video ended) and the time they entered their

guess about the subject’s ethnic background.

Respondents were then shown the “greeting” video of the same subject and asked the

same two questions. They were told that they were free to change their answers if they saw

something in the video that caused them to reassess their earlier guess. Finally, respondents

were shown the “greeting with name” video and, again, asked to guess the subject’s ethnic

background and to indicate their certainty about their guess.

If the respondent happened to be paired with one of the thirty-two subjects for whom we

had recorded a simulation/dissimulation video, then the respondent was shown one additional

video. Approximately half of the time they were shown the dissimulation video and half of the

time they were shown the simulation video. If the respondent was shown the simulation video

and if the subject in the video was a co-ethnic, then the respondent was shown the “co-ethnic

simulation” video; if the subject was a non-co-ethnic, then the respondent was shown the “non-

co-ethnic simulation” video. After seeing the video, the respondent was again asked to guess the

subject’s ethnic background and to indicate his or her certainty about the guess. The instructions

read to subjects for the experiment are provided in Appendix B.

After viewing the images and guessing the ethnic backgrounds of the twenty-three

subjects, respondents completed a questionnaire that collected further information about the parts

of the world they had visited and/or lived in; whether they had a roommate and, if so, of what

ethnic background; and, for each of our seven ethnic groups, whether they would feel

comfortable having a member of that group as a close kin by marriage. At the conclusion of the

experiment, respondents were paid their winnings. In addition to their $5 show up fee, the

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maximum a respondent could have earned was approximately $15.60. On average, respondents

earned $11.13.

ARE THERE DIFFERENCES IN GROUP IDENTIFIABILITY?

Table 1 reports the percentage of successful identifications (by which we mean viewings

in which the respondent’s guess of the subject’s ethnic identity matches the way the subject self-

identifies), broken down by subject and respondent group type. Included in brackets under each

identification success rate is the total number of respondent-subject pairings of that type. We

further break down the results by the level of information that respondents had about subjects.

Table 1(a) presents identification success rates at our lowest level of information, when

respondents were shown headshots of the subjects. Table 1(b) presents success rates at

intermediate levels of information, when respondents were shown the recorded video greetings

prepared by the subjects. Table 1(c) presents success rates for viewings at our highest level of

information, when respondents were shown video greetings of the subjects in which the subjects

provided their names.

Reading down the columns, it is clear that some ethnic groups are much more identifiable

than others. Respondents had relatively little difficulty correctly identifying Asian, Caucasian,

and African American students at all three levels of information. Identification success rates

surpassed 95 percent for Asian subjects and 80 percent for subjects from the other two groups.

Respondents had much more difficulty correctly categorizing Arab, Indian, and Persian/Iranian

students. At low levels of information – roughly analogous to a situation in which the

respondent passed the subject on the street – identification success rates were below 45 percent.

For Arab students, identification success rates were only 26 percent. As these results suggest,

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and as we will show more systematically in a moment, the ethnic group membership of the

subject is by far the most important predictor of identification success.

Figure 1 provides a graphical representation of the distribution of identification success

rates across individual subjects within each ethnic group. Subjects from each ethnic community

are ranked from least to most identifiable. As the Figure makes clear, there is substantial

variation in the extent of ethnic identifiability across the members of each community in our

sample.15 Subjects from groups that are most easily identified in aggregate (Asian, Caucasian,

and African American) tend to cluster at high levels of identification success even at the

individual level. Although there are individuals within each of these groups that cannot be easily

identified, the graphs are heavily weighted toward the right, with high most subjects identified

correctly 100 percent of the time, or nearly so. For Arabs, Indians, and Persians/Iranians,

however, the situation looks quite different. The mean identification success rate is much lower

and the distribution of rates across individuals is more varied.

Might the differences in identification success rates at the group and individual levels be

the result of a priori beliefs on the part of respondents about the likelihood that subjects of

different types will appear in the sample? For example, might identification rates for Arabs be

low because it never occurred to most respondents that Arab students would be in the subject

pool? While we intentionally selected groups that were well-represented on the UCLA and USC

campuses, this is reasonable surmise. As a check, we compared the total distribution of ethnic

guesses with the actual distribution of ethnic groups in our sample of subjects. The close match

between the two increases our confidence that the low rates of identification success among

15 Unfortunately, our group samples are too small to (necessarily) capture the whole range of phenotypical

variation within each group.

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some subject types reflect the difficulty of categorizing members of those groups, not a priori

beliefs about the likelihood that they would be encountered in the sample population. In

addition, prior to being asked to identify subjects’ backgrounds, the respondents had already

participated in two rounds of experimental games in which they had been exposed to 30

viewings of other subjects (see Habyarimana et al. 2004). So they almost certainly had a good

sense of the broad ethnic composition of the subject pool.

OTHER DETERMINANTS OF IDENTIFICATION SUCCESS

Our results so far suggest that identification success rates vary significantly across ethnic

groups. In particular, African American, Asian, and Caucasian subjects appear to be far easier to

identify than Arab, Indian, Latino/a or Persian/Iranian subjects. Next, we explore the other

factors that make successful identification more likely.

Are Some Groups Better at Categorizing than Others?

Reading across the rows in Table 1, it is apparent that the members of some ethnic groups

are more successful respondents than others. The variation in success rates across respondent

types is much narrower than the variation across subject groups (compare the degree of variation

in the row and column marginals), but there are nonetheless meaningful differences.

Persian/Iranian respondents exhibit the highest rates of identification success, surpassing the

average success rate in the sample (when headshots are viewed) by 10 percentage points.

Interestingly, the range of variation narrows as the amount of information that

respondents have about subjects increases. The gap between the most and least successful ethnic

groups decreases substantially (from 17.5 percent to 11.7 percent) as information levels increase

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from headshots to video greetings with names. More information dilutes the advantage that

some respondent groups have in identifying the backgrounds of others.

Does it Help to be an In-Group Member?

The design of the experiment also enabled us to assess the impact of “co-ethnicity” – a

respondent being paired with a subject from the same ethnic group – on identification success

rates. Approximately 25 percent of the 2,203 total viewings in the experiment were co-ethnic

pairings.

Table 1 provides a rough sense of how identification success rates vary depending on the

make-up of the pairing. For each type of subject, we highlight in bold the respondent type with

the highest identification success rate. To the extent that individuals are better able to identify

members of their own ethnic community than outsiders, we would expect the bold cells to be

arrayed along the diagonal. A quick look at Tables 1(a-c) reveals a near diagonal, particularly at

high levels of information. African Americans are the only group that deviates substantially

from this expectation.16

Table 2 provides clearer evidence of the importance of co-ethnicity for identification

success. On average, across all viewings, identification success rates for co-ethnic pairings were

83.8 percent as compared to 66.8 percent for non-co-ethnic pairings. This finding is robust across

16 We suspect that this result is a product of the miscoding by African American respondents of one

subject – a very light-skinned person who self-identified as African American. This said, one would need

to explain why African American respondents were more prone to miscoding this subject than members

of other groups. Previous work by social psychologists offers one potential answer: non-minority groups

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all three levels of information. Not surprisingly, the importance of co-ethnicity varies across

ethnic groups. For groups that are difficult to identify on average (e.g., Arabs, Indians, and

Persians/Iranians), identification success rates in co-ethnic pairings are substantially higher than

in non-co-ethnic pairings. The identification success rate for Persian/Iranian subjects, for

example, is more than twice as high in co-ethnic as in non-co-ethnic pairings. Co-ethnicity does

little to improve success rates where ethnic groups are already easy to identify (compare the

Persian/Iranian row with that for Asian, Caucasian, or even Latino subjects).

How Important is Information?

A key innovation in our experimental design is the introduction of different levels of

information. Across all viewings, the effect of information is small yet significant (see Table 2).

The identification success rate at high levels of information (when respondents are shown a

video greeting in which the subject revealed his or her name) is 75.6 percent as compared to 70.9

percent at low levels of information (when respondents were just shown a headshot of the

subject). This difference of 4.7 percentage points is much smaller than the co-ethnic effect

described above.

Increasing information also increases respondents’ certainty in their guesses. Average

certainty was 3.09 on scale from 1 (“a random guess”) to 4 (“most certain”) when respondents

were shown just the headshot and rose to an average of 3.33 when they were shown the video

image with the subject providing his or her name – a difference that is statistically significant.

tend to place individuals with unique features (including darker skin color) in what they call “extreme”

racial categories (Pettigrew, Allport, and Barnett 1958).

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As with co-ethnicity, information has a more powerful impact on identification success

when the subject is from a group that is not easily identifiable. For example, Arab subjects are

identified successfully 36.1 percent of the time when they provide their names and only 26.1

percent when respondents are shown just a headshot. Providing names of Latino/a, Indian, and

Persian/Iranian subjects also has a powerful impact on identification success.

Do Individual Characteristics Matter?

We also explored the impact of respondents’ individual-level characteristics on

identification success rates. In particular, we assessed the impact of respondents’ exposure to

and attitudes toward members of other groups on their ability to correctly categorize subjects.

Respondents with significant exposure to particular ethnic groups exhibited higher

success rates in identifying subjects from these groups than respondents without such exposure.

We assessed the level of exposure by asking respondents to list the ethnic backgrounds of their

roommates. When respondents had roommates of the same ethnic group as the subject being

viewed, the identification success rate was 82.2 percent. Respondents without roommates from

the same ethnic group as the subject achieved success rates of only 67.8 percent.

A second measure of exposure is the respondent’s age. Because our sample was

composed entirely of college students, there was not a great deal of variation in age. It was,

however, possible to compare recent arrivals to the university campus with those who had

already completed a year or more. Given the ethnically diverse student populations at both

UCLA and USC, this extra time on campus almost certainly exposed many respondents to more

people from outside their own ethnic groups than they had been exposed to previously, and this

may have led to higher identification success rates. Consistent with this hypothesis, students

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aged 19 and older recorded success rates of 4.6 percentage points higher than those 18 and

younger. The age effect provides an additional indication that exposure to a diversity of ethnic

groups may be an important predictor of identification success rates.

The ability of individuals to correctly identify the ethnic backgrounds of the people they

encounter may also be a function of attitudes toward members of different communities. Indeed,

this intuition is at the core of the literature on prejudice and ethnic categorization that we

reviewed earlier. To assess the impact of respondents’ attitudes on identification success, we

asked a battery of questions designed to measure the perceived social distance between

themselves and members of each of the six other groups in the experiment (Bogardus 1932). In

particular, we asked respondents whether they would feel comfortable having someone from

each ethnic group as a “close kin by marriage.” We then tested whether such attitudes had any

effect on the ability of respondents to categorize members of each group. As the results reported

in Table 2 reveal, that higher degrees of comfort with a subject’s ethnic group are, in fact,

associated with higher success rates in guessing the identity of that group’s members.

PUTTING IT ALL TOGETHER

Thus far, we have analyzed the factors that affect identification success rates

independently of one another. Table 3 presents the results of a series of probit regressions that

assess their effects together. For ease of interpretation, we report marginal coefficient estimates

(with values for the other explanatory variables set to their means). Column 1 reports a model

that includes only respondent-specific determinants of identification success with low

information (headshot only). As we might expect from the results reported in Table 2, measures

of respondents’ exposure to and attitudes toward members of the subject group enter

significantly. Respondents who have a roommate of the subject’s ethnic group and who feel

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comfortable with a family member marrying someone of that ethnic group are more likely to

successfully identify the subject’s ethnic background. In addition, moving from a non-co-ethnic

pairing to a co-ethnic pairing increases the probability of identification success by 15 percentage

points. Age is substantively, but not statistically, significant in this specification.17

Columns 2 and 3 introduce subject group effects, where the omitted ethnic group

category is Caucasian. The results confirm the findings from Table 2: Arabs, Indians,

Persians/Iranians, and Latino/as are significantly more difficult to identify than Caucasians,

African Americans, and Asians. For example, compared to a Caucasian subject, an Arab subject

is 57.7 percent less likely to be correctly identified. Although the introduction of subject group

effects cuts the co-ethnic coefficient in half, the underlying finding remains: respondents are

much better able to identify members of their own groups than outsiders. Column 3, which

includes both subject group effects and respondent characteristics, makes it clear that the former

dominates the latter. Once subject characteristics are controlled for, social distance and

roommate effects disappear. However, a new variable – the number of world regions in which

the respondent has lived – enters negatively and significantly.

Column 4 adds respondent group effects to produce a complete model. The results

reinforce our earlier finding that, at low levels of information, some ethnic groups are

systematically better able to identify subjects than others. If a respondent is Persian/Iranian or

17 Increases in the level of education of the respondent’s father (a rough measure of the respondent’s

socio-economic status) are associated with a higher probability of identification success, while having

lived in the region in which the subject’s ethnic group originated tends to reduce the likelihood of success.

We do not read too much in to these findings, however, since both of these effects cease to be significant

when controls for subject characteristics are added to the model.

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Asian, her probability of identification success increases 11.5 or 8.5 percentage points

respectively, relative to a Caucasian respondent.

Column 5 replicates the complete model (from column 4) on the sample of high

information viewings. While subject group effects are still strong, they are substantially reduced

in size. Subject’s names provide a powerful source of information for most respondents and this

reduces the difficulty of identifying members of the most difficult-to-classify subject groups.

The significance of being in a co-ethnic pairing also disappears, indicating that co-ethnicity

provides an advantage only at low levels of information – perhaps because respondents can draw

on visual cues that may not be obvious to others. The respondent group effect among

Persians/Iranians also disappears at high information levels.

Thus far, we have defined identification success in terms of whether the respondent

identifies the subject in terms of the ethnic group with which the subject self-identifies. An

alternative, less stringent, definition of success is whether the guess of the respondent accords

with the modal guess of all respondents who were shown pictures of that subject. We replicate

our main model using this broader understanding of identification success in column 6.

The results suggest that subject group effects become less important when we give

respondents the cushion of needing only to match the best guess of the population. Under these

circumstances, respondents tend to correctly guess the ethnic backgrounds of the most

identifiable subjects from each group. When they misidentify individuals, they tend to do so in a

similar way to the respondent population in general.

All of the models in Table 3 also report the association between identification success

and the certainty of the respondent about his or her guess. Certainty is measured in two different

ways: in terms of the time elapsed before the respondent enters his or her response and in terms

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of the level of certainty he or she indicates. In every specification, longer response times are

associated with lower identification success and greater certainty is associated with higher

success. The latter suggests that respondents are able to make fairly accurate assessments of

whether or not they are likely to be correct in their guesses. A multinomial logit specification

using the full model in column 3 (not shown) reveals that respondents take longer to respond

when they are shown the image of a subject from an ethnic group that is, on average, difficult to

identify.

MAKING SENSE OF MISIDENTIFICATION

Table 4 explores ethnic misidentifications. We distinguish between two different kinds

of misidentification: false positives (where, for example, a respondent shown an image of a non-

Latino identifies him as Latino) and false negatives (where a respondent shown an image of a

Latino identifies him as something other than Latino) – Figure 2 illustrates. As Table 4 makes

clear, the frequency of false positives and false negatives varies significantly across groups.

Whereas respondents incorrectly identified non-Caucasians as Caucasian 11 percent of the time,

they incorrectly identified non-African Americans as African American less than 1 percent of the

time. Meanwhile, Arabs, Indians, and Persians/Iranians were extremely likely to be

misidentified as members of other groups. This happened nearly three-quarters of the time with

the Arab subjects in our sample and more than half the time with Indian and Perisan/Iranian

subjects.

In contradiction to theories that assume that ethnic groups are able to police their

boundaries, we find that subjects miscoded fellow group members as non-group members 16

percent of the time and miscoded non-group members as group members 7 percent of the time.

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The gap between these two types of misidentification suggests that a bias runs against admitting

non-co-ethnics to one’s group. This is a rather remarkable finding given that the stakes for

making a Type I error were effectively zero in the context of the experiment.

Apart from its intrinsic interest, data on misidentification can also help measure the social

distance between ethnic groups. Groups whose members are commonly mistaken for one

another could be coded as “close” and those whose members are rarely or never mistaken for one

another could be coded as “distant.” Although Casselli and Coleman (2002) base a theoretical

model of conflict on a similar notion of social distance, we know of no attempts to measure

social distance in this way empirically. Table 5 provides two approaches to measuring the

distance between ethnic groups. Table 5(a) presents the distance between ethnic groups

calculated as the average of false positives and false negatives. Higher rates of misidentification

within a given pairing indicate greater proximity of the two groups. Reading down the columns,

it is clear that there is significant variation in the distance between ethnic groups. Arabs, for

example, are most often misidentified as Caucasian, Latino/a, and Persian/Iranian. They are

misidentified least often as African American and Asian. Interestingly, this measure of social

distance correlates with one based on affinities (as operationalized by willingness to accept a

person into one’s family by marriage). Caucasian, Latino/a, and Persian/Iranian respondents are

the most willing to accept Arabs as members of their families while Asians indicate an

unwillingness to accept Arabs into their families.

Table 5(b) presents a measure of social distance based purely on false positives –

potentially a cleaner measure of how often the identities of members of different groups are

confused by observers. The patterns are similar to those generated earlier. Again, Caucasian,

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Latino/a, and Persian/Iranian subjects are most likely to be misidentified as Arabs, while African

American and Asian subjects are virtually never misidentified.

HOW DIFFICULT IS IT FOR SUBJECTS TO PASS?

One of the strengths of this study’s design lies in our ability to control and vary the level

of information that respondents have about subjects’ backgrounds. Even so, the regulated

information we provide does have an aspect of artificiality. In real world situations where the

stakes of misidentification are high, individuals will often collect additional information about

other peoples’ backgrounds before they make their decisions about how to assign these people to

ethnic categories. Although still one-sided (only the subject speaks, and no opportunity is

provided for the respondent to interrogate the subject), the simulation and dissimulation videos

described earlier provide a better approximation of such real world interactions. They also

permit us to investigate the ability of individuals to pass as members of groups different from

their own.

Table 6(a) reveals that rates of identification success reach their highest levels for

viewings in which the subject sees a simulation video.18 The identification success rate across all

viewings reaches 88.5 percent in the simulation sub-sample, exceeding the success rate at even

the highest previous levels of information (the video in which the subject provided his or her

name), where the success rate was 75.6 percent. Providing subjects with the opportunity to

18 This holds across all ethnic groups except for African Americans. Again, because one key subject in

the African American sample was light-skinned, many African American respondents, along with others

in the general population, assumed that the subject was trying to pass as an African American even when

the subject provided an explanation for her appearance in the simulation video.

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convince respondents of their true ethnic background has a particularly powerful impact on

raising identification success rates for those groups that were most difficult to identify at lower

levels of information.

But providing subjects with the opportunity to mislead respondents about their ethnic

backgrounds substantially reduces identification success rates. As Table 6(b) indicates, the

overall success rate drops to 55.2 percent with dissimulation, from a success rate of 77.3 percent

for the dissimulation sub-sample when respondents viewed only a video greeting in which the

subject provided his or her name. As with identifiability, the ability to pass is something that

varies with the ethnic group of the subject. Arabs, Caucasians, Indians, and Latinos are

particularly good at passing, reducing the ability of respondents to correctly identify them by

between 27 and 39 percentage points.

Recall that the subjects that participated in the dissimulation exercise were told to pretend

that they were in a situation in which it was important that they convince the person who would

view the dissimulation video that they belonged to an ethnic group different from their own. We

provided subjects with a list of ethnic groups and asked them to select one of which they would

try to pass as a member. Given these instructions, subjects should have chosen a group in which

they thought they could reasonably expect to pass successfully. The choices that subjects made

should therefore provide some indication of the “revealed” distance between groups. Although

the sample of dissimulators is small (N = 32), it is clear that subjects tended to choose groups in

which they were more likely to pass successfully. Arabs, for example, were most likely to

dissimulate as Latino/as or Persians/Iranians, which supports our conjecture based on the

findings in Table 5 that these three groups are more proximate to one another. Arab subjects did

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not tend to dissimulate as African American or Asian (and vice versa) – groups we measured as

particularly distant from Arabs (again, see Table 5).

In Table 7, we examine the determinants of successful passing. We employ three

different definitions of successful passing. In the first (columns 1-3), we ask whether the

respondent correctly identified the true ethnicity of the subject in spite of the fact that he or she

viewed a dissimulation video. A second definition (column 4) asks whether the respondent, after

seeing the dissimulation video, changed her answer from the correct to an incorrect ethnic

category.19 A final definition (column 5) asks whether the ethnic guess of the respondent

matched the ethnic group in which the subject was trying to pass. Thus, while the first definition

effectively asks “did the respondent see through the dissimulating subject’s attempt to pass?” this

third definition asks “did the subject fool the respondent into believing that he or she really

belonged to the group in which he or she professed to be a member?”

Column 3 shows that a number of individual and subject group effects are important for

successful passing. The older a subject is and the higher his or her SAT scores, the less likely

the respondent will be able to correctly identify him or her when he or she is trying to pass. Co-

ethnicity also gives a respondent a leg up, making it more difficult for the subject to deceive him

or her. Finally, group effects again loom large. Asians have more difficulty trying to pass

(relative to Caucasians), while Indians and Latinos are substantially more successful.

A number of these effects remain large and significant as we move to increasingly

stringent definitions of success. In particular, when we ask whether subjects were able to

convince respondents of their false identity (definition 3, reported in column 5), age and SAT

19 Recall that respondents had first seen, in secession, the head shot, video greeting, and video greeting

with name before they were then shown the dissimulation video of the same subject.

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score emerge as powerful predictors. Asians, again, face the most difficulty in credibly

convincing others that they are not in fact Asian. And, interestingly, Latino/a respondents are

significantly less likely to believe the false story that subjects are telling (in columns 4 and 5).

One explanation for this finding is that many subjects tried to pass as Latino/a by speaking in

Spanish in their dissimulation video and “true” Latinos/as were able to see through this ruse.

POTENTIAL WEAKNESSES OF THE EXPERIMENTAL DESIGN

Our main goal in this paper has been to document that seamless ethnic identifiability

cannot be assumed and to show that it varies in systematic ways across groups. Our

experimental results make both of these points clear. But how far can we go in asserting their

generalizability?

Three major concerns regarding external validity merit consideration. The first is with

respect to the criterion we employ for determining successful ethnic identification – i.e., whether

there is a match between the respondent’s guess and the way the subject identifies him or herself.

How individuals choose to identify themselves may not always be related to how they “should”

be identified, as determined by genetics or family lineage. Indeed, previous work in social

psychology explicitly avoids the self-identification criterion, instead relying on panels of experts

to identify the ethnic group of a subject. Such an approach sounds odd in today’s world, where

ethnicity tends to be viewed more as a product of subjective self-definition than of genetics.

Nonetheless, the self-identification criterion is not beyond criticism. To the extent that the

failure of respondents to identify subjects correctly is a function of how the subjects themselves

choose to self-identify, this would lead us to overestimate subject group differences in

identifiability.

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A second concern relates to the small sample size of some of our subject groups. While

our overall subject and respondent populations are similar to or larger than those in previous

experiments of this type, it is nevertheless fair to assert that our samples are unlikely to capture

the full range of phenotypical variation within each ethnic group in the real population.

Moreover, it is difficult for us to assess how our sample of university students differs

phenotypically or attitudinally from those who never made it to college (or at least, not to the two

selective universities from whose student populations our participants were drawn). To the

extent that students who “look ethnic” face discrimination that makes it more difficult for them

to gain entry to selective universities, it is possible that our sample substantially understates the

true range of variation in identifiability.

A final issue is the relative weakness of our results on the importance of exposure to and

attitudes toward other ethnic groups. Most of these individual-level effects are swamped by the

power of subject group dummy variables in the full model specification. Because we conducted

this experiment on a university campus where most individuals are exposed to a whole range of

ethnic groups on a regular basis, our sample may bias the results against finding strong

individual-level effects of attitudes and exposure. The strength and consistency of our finding on

the importance of age lends plausibility to this argument, suggesting that there is something

systematically different about students that are just arriving on campus as compared to those who

have been immersed in a diverse environment for some time.

CONCLUSION: IMPLICATIONS FOR THEORIES OF ETHNIC POLITICS

Our experimental evidence undermines the assumption, implicit or explicit in much of

the micro-level theoretical work on ethnic politics, that ethnic identifiability is a non-issue. In

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contradiction to the assumption that individuals can seamlessly pigeonhole the people they

encounter into their correct ethnic categories, our respondents were unable to correctly identify

the ethnic backgrounds of the subjects whose images they are shown more than 30 percent of the

time. Our findings also show that identifiability varies across ethnic groups, across individuals

within groups, across levels of information, and across co-ethnic and non-co-ethnic pairings.

Our exploration of “passing” also generates results that are relevant to theories of ethnic politics.

In particular, the experiment suggests that members of some ethnic groups are much better able

to pass than others, and that these group-specific effects are far more important than individual-

level factors, including experience and intelligence.

Apart from the caution our findings suggest for models that depend on the ability of

actors to categorize their interacting partners, our results have at least four implications for

theories of ethnic competition and conflict more generally.

First, the results suggest that collective action may be easier for some ethnic groups than

for others. It has been suggested that one of the reasons that ethnicity so often emerges as an

axis of political mobilization is because ethnic groups possess institutions that facilitate the

punishment of defection by in-group members. But if identifiability is not perfect, then the

ability of groups to police their members will be undermined and the advantage they have for

collective action will disappear. To the extent that identifiability varies systematically across

ethnic groups, the ability of ethnic groups to achieve collective ends should vary as well.

Second, the results show that passing may be easier for some individuals and groups than

for others. Much contemporary work on ethnicity underscores the fact that individuals

sometimes have incentives to pass. Our findings confirm that people are indeed able to do this,

but they also show that individuals’ ability to pass varies with group and individual-level

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characteristics. This has implications for the permeability of group boundaries and the ability of

groups to police them.

Third, the findings suggest that in bilateral transactions, individual choices may depend

on how much information a player has about the identity of his or her partner. Theorists cannot

assume that individuals play strategies conditional on the identity of their partner, or that the

identity of individuals is common knowledge within ethnic groups or the population at large.

The impact of a partner’s identity on a player’s strategy will be a function of the degree of

information that the player has about the partner, and thus the certainty that he or she has about

the partner’s background.

Finally, the experiment makes it clear that the costs involved in gathering information

about the ethnic identity of individuals may vary across groups. Theories that rely on within-

group punishment strategies as an enforcement mechanism cannot realistically ignore the costs

that may be incurred in establishing the ethnic identity of particular individuals. Our findings

suggest that these costs may be higher for some groups than others.

While the assumption that the ethnic backgrounds of individuals are readily apparent has

facilitated theoretical analysis, it has also prevented us from studying important aspects of ethnic

processes that should no longer be overlooked. Variation in identifiability may have real

consequences, as the stories of ethnic identification in Sri Lanka and Burundi suggest. Taking

these differences seriously – and incorporating them into models of ethnic politics – is a critical

next step in producing better theories that link ethnicity to cooperation and conflict.

34

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BIBLIOGRAPHY Akerlof, George, 1970, “The Market for ‘Lemons’: Quality Uncertainty and the Market

Mechanism,” Quarterly Journal of Economics 84, pp. 488-500. Akerlof, George, 1976, “The Economics of Caste and of the Rat Race and Other Woeful Tales,”

Quarterly Journal of Economics 90, pp. 599-617. Allport, Gordon and Bernard Kramer, 1946, “Some Roots of Prejudice,” The Journal of

Psychology 22, p. 9-39. Barth, Fredrik, 1969, Ethnic Groups and Boundaries (Boston: Little Brown). Blasovich, Jim, Natalie Wyer, Laura Swart, and Jeffrey Kibler, 1997, “Racism and Racial

Categorization,” Journal of Personality and Social Psychology 72, p. 1364-1372. Becker, Gary S., 1971, The Economics of Discrimination, 2nd edition (Chicago: University of

Chicago Press). Bogardus, Emory, 1933, “A Social Distance Scale,” Sociology and Social Research 17, p. 265-

71. Caselli, Francseco and Wilbur John Coleman, 2002, “On the Theory of Ethnic Conflict,” mimeo,

Department of Economics, Harvard University. Chandra, Kanchan, 2004, Why Ethnic Parties Succeed: Patronage and Ethnic Headcounts in

India (New York: Cambridge University Press). Fearon, James D., 1999, “Why Ethnic Politics and ‘Pork’ Tend to Go Together,” mimeo,

Department of Political Science, Stanford University. Fearon, James D. and David D. Laitin, 1996, “Explaining Interethnic Cooperation,” American

Political Science Review 90 (4), p. 715-35. Ferraro, Paul J. and Ronald G. Cummings, 2004, “Experimental Approaches to Understanding

Intercultural Conflict over Resources,” mimeo, Department of Economics, Georgia State University.

Fershtman, Chaim and Uri Gneezy, 2001, "Discrimination in a Segmented Society: An

Experimental Approach," Quarterly Journal of Economics 116, No. 1, p. 351-377. Gil-White, Francisco J, 2004, “Ultimatum Game with an Ethnicity Manipulation: Results from

Bulgan Sum, Mongoloa,” in Joseph Henrich et al., Foundations of Human Sociality: Economic Experiments and Ethnographic Evidence from Fifteen Small-Scale Societies (New York: Oxford University Press), pp. 260-304.

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Greif, Avner, 1989, “Reputation and Coalitions in Medieval Trade,” Journal of Economic History 49 (December), pp. 857-882.

Habyarimana, James, Macartan Humphreys, Daniel N. Posner, and Jeremy M. Weinstein, 2004,

“Ethnic Preferences and Ethnic Institutions: Results from Experimental Work in California,” unpublished paper.

Harris, David, 2002, “In the Eye of the Beholder: Observed Race and Observer Characteristics,”

PSC Research Report No. 02-522, Population Studies Center, University of Michigan. Horowitz, Donald L., 2001, The Deadly Ethnic Riot (Berkeley and Los Angeles: University of

California Press). Human Rights Watch, 2002, “‘We Are Not the Enemy’ Hate Crimes Against Arabs, Muslims,

and Those Perceived to be Arab or Muslim After September 11,” 14, 6 (November). Humphreys, Macartan and Habaye ag Mohamed, 2002. “Senegal and Mali.” Working Paper on

the Economics of Crime and Violence in Sierra Leone, World Bank / Center for United Nations Studies at Yale. Presented at Yale, April 12-15.

Isaacs, Harold, 1975, “Idols of the Tribe,” in Nathan Glazer and Daniel P. Moynihan, Ethnicity:

Theory and Experience (Cambridge, MA: Harvard University Press), pp. 29-52. Laitin, David D., 1995, “Marginality: A Microperspective,” Rationality and Society 7 (January),

pp. 31-57. Landa, Janet Tai, 1994, Trust, Ethnicity, and Identity: Beyond the New Institutional Economics

of Trading Networks (Ann Arbor: University of Michigan). Lent, Richard, 1970, “Binocular Resolution and Perception of Race in the United States,” British

Journal of Psychology 61, p. 521-33. Pettigrew, Thomas, Gordon Allport, and Eric Barnett, 1958, “Binocular Resolution and

Perception of Race in South Africa,” British Journal of Psychology 49, p. 265-278. Posner, Daniel N., forthcoming, Institutions and Ethnic Politics in Africa (New York: Cambridge

University Press). Secord, Paul, 1959, “Stereotyping and favorableness in the perception of Negro faces,” Journal

of Abnormal Social Psychology 59, p. 309-315. Tajfel, H., Billig, M. G., Bundy, R. P., and Flament, C., 1971, “Social categorization and

intergroup behavior,” European Journal of Social Psychology 1, p. 149-178.

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Table 1: Identification Success a. Headshots Only Ethnic Group of Subject (whose image is viewed)

African American

Arab

Asian

Caucasian

Indian

Latino/a

Persian/Iranian

Total

African American

72.41 (29)

17.65 (17)

93.48 (46)

85.19 (54)

18.18 (11)

65.85 (41)

25 (32)

65.22 (230)

Arab

89.47 (19)

43.75 (16)

96.88 (32)

86.05 (43)

33.33 (12)

44.44 (27)

41.67 (12)

70.19 (161)

Asian

80 (50)

23.68 (38)

97.18 (142)

82.20 (118)

55 (20)

64.10 (78)

35.14 (37)

74.12 (483)

Caucasian

81.16 (69)

25 (52)

94.81 (135)

87.34 (237)

48.39 (31)

47.58 (124)

35 (60)

70.48 (708)

Indian

84.62 (13)

27.78 (18)

86.96 (23)

62.69 (27)

100 (5)

57.14 (12)

37.50 (8)

63.48 (115)

Latino/a

81.25 (32)

22.22 (27)

91.38 (58)

82.93 (82)

10 (10)

63.64 (88)

40 (25)

68.32 (322)

Persian/ Iranian

80.56 (36)

33.33 (12)

100 (34)

87.50 (48)

80 (5)

70 (30)

78.95 (19)

80.98 (184)

Ethn

ic G

roup

of R

espo

nden

t (w

ho v

iew

s sub

ject

’s im

age)

Total

80.65 (248)

26.11 (180)

95.11 (470)

84.40 (609)

44.68 (94)

57.95 (409)

38.86 (193)

70.90 (2203)

b. Video Greeting Ethnic Group of Subject (whose image is viewed)

African American

Arab

Asian

Caucasian

Indian

Latino/a

Persian/Iranian

Total

African American

72.41 (29)

17.65 (17)

95.65 (46)

83.33 (54)

18.18 (11)

65.85 (41)

31.25 (32)

66.09 (230)

Arab

89.47 (19)

37.50 (16)

96.88 (32)

83.72 (43)

41.67 (12)

55.56 (27)

50 (12)

72.05 (161)

Asian

82.00 (50)

23.68 (38)

95.77 (142)

86.44 (118)

60 (20)

58.97 (78)

32.43 (37)

74.12 (483)

Caucasian

78.26 (69)

25 (52)

96.30 (135)

87.76 (237)

58.06 (31)

50 (124)

40 (60)

71.89 (708)

Indian

92.31 (13)

22.22 (21)

91.30 (23)

74.07 (27)

100 (5)

38.10 (21)

25 (8)

62.61 (115)

Latino/a

81.25 (32)

25.93 (27)

91.38 (58)

82.93 (82)

20 (10)

67.05 (88)

40 (25)

69.88 (322)

Persian/ Iranian

83.33 (36)

33.33 (12)

100 (34)

81.25 (48)

80 (5)

70 (30)

78.95 (19)

79.89 (184)

Ethn

ic G

roup

of R

espo

nden

t (w

ho v

iew

s sub

ject

’s im

age)

Total

81.05 (248)

46 (180)

95.53 (470)

85.06 (609)

51.06 (94)

58.19 (409)

40.93 (193)

71.67 (2203)

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c. Video Greeting with Name Ethnic Group of Subject (whose image is viewed)

African American

Arab

Asian

Caucasian

Indian

Latino/a

Persian/ Iranian

Total

African American

86.21 (29)

23.53 (17)

84.78 (46)

85.19 (54)

9.09 (11)

82.93 (41)

34.38 (32)

69.57 (230)

Arab

78.95 (19)

56.25 (16)

93.75 (32)

81.40 (43)

66.67 (12)

66.67 (27)

41.67 (12)

74.53 (161)

Asian

82 (50)

36.84 (38)

95.07 (142)

82.20 (118)

75 (20)

73.08 (78)

29.73 (37)

76.60 (483)

Caucasian

82.61 (69)

40.38 (52)

95.56 (135)

86.92 (237)

61.29 (31)

71.77 (124)

55 (60)

78.25 (708)

Indian

100 (13)

27.78 (18)

82.61 (23)

81.48 (27)

80 (5)

61.90 (21)

37.50 (8)

68.70 (115)

Latino/a

87.50 (32)

29.63 (27)

89.66 (58)

84.15 (82)

30 (10)

71.59 (88)

48 (25)

72.98 (322)

Persian/ Iranian

72.22 (36)

33.33 (12)

94.12 (34)

79.17 (48)

80 (4)

86.67 (30)

94.74 (19)

80.43 (184)

Ethn

ic G

roup

of R

espo

nden

t (w

ho v

iew

s sub

ject

’s im

age)

Total

82.66 (248)

36.11 (180)

92.77 (470)

84.24 (609)

57.45 (94)

73.35 (409)

48.19 (193)

75.62 (2203)

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Table 2: Determinants of Identification Success

Percent of Subjects Correctly Identified

Difference (p-value)

Subject is From

Respondent’s Ethnic Group

83.77 (536)

In-group/ Out-group

Pairing

Subject is Not From Respondent’s Ethnic Group

66.77 (1667)

17.00 (0.00)

Low (Headshot)

70.90 (2203)

Level of Information

High (Video Greeting with Name)

75.62 (2203)

4.72 (0.00)

Respondent Does Not Have a Roommate

from the Subject’s Ethnic Group

67.82 (1731)

Exposure to Members of the Subject’s Ethnic Group

Respondent Has a Roommate from the Subject’s Ethnic Group

82.20 (472)

14.38 (0.00)

18 Years or Younger

67.39 (506)

Respondent’s Age

19 Years or Older

71.95 (1697)

4.56 (0.05)

Respondent Would Not Feel Comfortable Having Someone of the Subject’s Ethnic

Group as Close Kin by Marriage

62.10 (694)

Social Distance between Respondent and Members of Subject’s Ethnic Group

Respondent Would Feel Comfortable

Having Someone of the Subject’s Ethnic Group as Close Kin by Marriage

74.95 (1509)

12.85 (0.00)

Table 2 Notes: All comparisons (except the second) are based on viewings in which the respondent sees a headshot of the subject. Column 4 reports the p-value of a test of the null hypothesis that the identification success rates are equal across the two categories.

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Table 3: Determinants of Successful Ethnic Identification

Dependent Variable: Does the Ethnic Guess of the Respondent Match the

Self-Reported Ethnic Group of the Subject?

Dependent Variable: Does the Ethnic Guess of the Respondent Match the “Best Guess” of

the Population? (1) (2) (3) (4) (5) (6)

-0.093 -0.099 -0.100 -0.103 -0.080 -0.085 Seconds Elapsed Before Response (2.94)** (3.36)** (3.36)** (3.50)** (3.77)** (4.07)**

Certainty of Respondent 0.164 0.109 0.109 0.107 0.116 0.103 (9.53)** (5.64)** (5.63)** (5.53)** (7.23)** (7.06)**

Co-ethnic Pairing 0.150 0.070 0.053 0.062 0.027 0.045 (5.00)** (3.25)** (2.14)* (2.64)** (1.18) (2.12)*

Respondent Age > 18 0.047 0.051 0.047 0.036 0.046 (1.96) (2.15)* (1.97)* (1.94) (2.18)*

Respondent is Female 0.041 0.029 0.024 -0.012 0.048 (1.95) (1.38) (1.05) (0.56) (2.60)**

-0.015 -0.001 0.007 0.016 0.035 Respondent is UCLA Student (0.54) (0.02) (0.25) (0.60) (1.52) 0.016 0.016 0.014 0.006 0.015 Respondent’s Father’s Education

(2.03)* (1.95) (1.85) (0.81) (2.34)* -0.007 -0.016 -0.027 -0.023 -0.021 Number of World Regions

Respondent has Visited (0.95) (2.13)* (2.39)* (2.05)* (2.23)* -0.097 0.005 -0.017 0.037 -0.006 Respondent has Lived in Region of

Ethnic Group of Subject (2.59)** (0.17) (0.53) (1.12) (0.23) -0.041 0.022 0.025 0.012 0.008 Respondent has Close Friend from

Region of Subject’s Ethnic Group? (1.12) (0.75) (0.83) (0.43) (0.31) 0.066 0.019 0.042 0.032 0.016 Respondent is Comfortable with

Someone of Subject’s Group Marrying Relative

(3.24)** (1.14) (2.18)* (1.59) (0.98)

0.118 0.031 0.042 -0.023 0.048 Respondent has Roommate of Same Ethnic Group as Subject? (4.61)** (1.26) (1.76) (0.99) (2.03)* African American Subject -0.102 -0.106 -0.106 -0.074 -0.060

(0.77) (0.79) (0.79) (0.64) (0.73) Arab Subject -0.577 -0.576 -0.566 -0.475 -0.236

(4.09)** (3.88)** (3.78)** (3.67)** (2.98)** Asian Subject 0.124 0.113 0.115 0.045 0.061

(1.55) (1.34) (1.36) (0.64) (0.92) Indian Subject -0.363 -0.369 -0.356 -0.246 -0.307

(3.56)** (3.57)** (3.44)** (3.02)** (4.25)** Latino/a Subject -0.240 -0.261 -0.250 -0.138 -0.125

(2.69)** (2.83)** (2.72)** (1.61) (2.20)* Persian/Iranian Subject -0.424 -0.430 -0.413 -0.337 -0.316

(5.34)** (5.28)** (5.04)** (4.41)** (5.16)** -0.005 -0.030 0.022 African American Respondent (0.16) (0.92) (0.70)

Arab Respondent 0.085 -0.005 0.062 (1.88) (0.10) (1.75)

Asian Respondent 0.085 -0.010 0.057 (2.72)** (0.48) (2.00)*

Indian Respondent 0.048 -0.030 0.040 (1.03) (0.68) (0.97)

Latino/a Respondent 0.021 -0.042 0.005 (0.69) (1.41) (0.17)

Persian/Iranian Respondent 0.115 0.012 0.021 (2.80)** (0.33) (0.59)

Information Level Headshot Headshot Headshot Headshot Video w Name Headshot Observations 2203 2203 2203 2203 2203 2203

Table 3 Notes: Probit estimation, with marginal coefficient estimates (at mean values for the explanatory variables). Robust Z statistics are in parentheses. Significantly different than zero at 95% (*), 99% (**) confidence. Regression disturbance terms are clustered at the subject level. The omitted ethnic group category of subjects and respondents is Caucasian.

40

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Table 4: Distribution of False Positives and False Negatives by Group

False Positives (Type I Errors)

False Negatives (Type II Errors)

African American

0.87 (1955)

19.35 (248)

Arab

4.45 (2023)

73.89 (180)

Asian

1.10 (1733)

4.89 (470)

Caucasian

11.36 (1594)

15.60 (609)

Indian

3.51 (2109)

55.32 (94)

Latino/a

7.80 (1794)

42.33 (411)

Ethn

ic G

roup

Persian/Iranian

6.12 (2010)

61.14 (193)

Table 5: Measures of Social Distance

a. Average of False Positives and False Negatives African

American

Arab

Asian

Caucasian

Indian

Latino/a Arab

1.24 (5)

Asian

0.22 (2)

0.53 (5)

Caucasian

2.02 (10)

17.34 (73)

0.22 (2)

Indian

1.01 (5)

10.23 (24)

0.96 (5)

3.97 (10)

Latino/a

6.1 (35)

11.73 (54)

2.42 (21)

12.13 (112)

6.54 (37)

Persian/ Iranian

1.62 (8)

16.61 (62)

0.88 (4)

11.15 (69)

17.94 (45)

10.45 (53)

b. False Positives Only African

American

Arab

Asian

Caucasian

Indian

Latino/a Arab

0.81 (2)

Asian

0 (0)

0 (0)

Caucasian

4.03 (10)

32.22 (58)

0.43 (2)

Indian

2.02 (5)

5.56 (10)

0.85 (4)

0.49 (3)

Latino/a

9.27 (23)

18.33 (33)

1.91 (9)

6.40 (39)

5.74 (7)

Persian/ Iranian

3.23 (8)

16.11 (29)

0.21 (1)

6.24 (38)

24.47 (23)

5.87 (24)

41

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Table 6: Identification Success with Simulation and Dissimulation a. Simulation (truth-telling) Ethnic Group of Subject (whose image is viewed)

African American

Arab

Asian

Caucasian

Indian

Latino/a

Persian/ Iranian

Total

African American

50 (2)

25 (4)

100 (13)

100 (11)

100 (2)

83.33 (6)

100 (5)

88.37 (43)

Arab

66.67 (3)

100 (8)

100 (11)

100 (2)

100 (3)

100 (2)

96.30 (27)

Asian

80 (5)

25 (4)

97.37 (38)

78.57 (28)

100 (3)

92.86 (12)

77.78 (9)

86 (100)

Caucasian

81.82 (11)

66.67 (9)

100 (38)

96.67 (60)

100 (2)

86.39 (22)

100 (12)

93.55 (155)

Indian

40 (5)

100 (5)

100 (3)

100 (2)

100 (2)

100 (1)

83.33 (18)

Latino/a

66.67 (3)

33.33 (3)

90.91 (11)

72.73 (11)

100 (2)

81.25 (16)

100 (6)

80.77 (52)

Persian/ Iranian

60 (5)

100 (6)

75 (12)

100 (1)

75 (4)

100 (3)

80.65 (31)

Ethn

ic G

roup

of R

espo

nden

t (w

ho v

iew

s sub

ject

’s im

age)

Total

73.08 (26)

46.43 (28)

98.32 (119)

89.71 (136)

100 (12)

86.57 (67)

94.74 (38)

88.50 (426)

b. Dissimulation (trying to pass) Ethnic Group of Subject (who is trying to pass as a member of a different group)

African American

Arab

Asian

Caucasian

Indian

Latino/a

Persian/ Iranian

Total

African American

40 (5)

0 (3)

88.89 (9)

50 (14)

0 (6)

42.86 (7)

45.45 (44)

Arab

33.33 (3)

25 (4)

87.50 (8)

28.57 (7)

0 (3)

50 (2)

100 (1)

46.43 (28)

Asian

40 (5)

14.29 (7)

87.18 (39)

41.67 (24)

66.67 (3)

18.18 (11)

28.57 (7)

55.21 (96)

Caucasian

50 (6)

22.22 (9)

84.62 (39)

65 (60)

0 (5)

25 (24)

28.57 (14)

55.41 (157)

Indian

0 (0)

100 (6)

57.14 (7)

0 (0)

16.67 (6)

100 (2)

54.17 (24)

Latino/a

66.67 (3)

0 (5)

80 (20)

62.50 (24)

35.71 (14)

66.67 (3)

57.97 (69)

Persian/ Iranian

66.67 (3)

33.33 (3)

92.31 (13)

37.50 (8)

50 (2)

50 (4)

85.71 (7)

67.50 (40)

Ethn

ic G

roup

of R

espo

nden

t (w

ho v

iew

s sub

ject

’s im

age)

Total

48 (25)

15.15 (33)

86.57 (134)

55.56 (144)

21.43 (14)

25.37 (67)

48.78 (41)

55.24 (458)

42

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Table 7: Determinants of Successful Passing

Dependent Variable: Does the Ethnic Guess of the Respondent Match the Self-Reported Ethnic Group of the

Subject?

Dependent Variable: Does the Respondent Change His/Her Guess from the Correct to the Incorrect

Category?

Dependent Variable: Does the Ethnic Guess of the Respondent Correspond with the Ethnic Group in

which the Subject Tried to Pass?

(1) (2) (3) (4) (5) Subject Age -0.098 -0.097 -0.098 -0.039 0.066

(2.98)** (2.38)* (2.46)* (1.92) (2.32)* Subject Female -0.045 0.139 0.125 -0.004 -0.140

(0.32) (1.03) (0.95) (0.05) (1.33) -0.004 0.039 0.039 -0.027 -0.053 Father’s Education (0.08) (0.96) (0.93) (1.24) (1.25)

SAT Score -0.088 -0.215 -0.221 0.014 0.168 (1.00) (2.28)* (2.32)* (0.30) (2.15)*

-0.333 -0.340 -0.197 0.138 African American Subject (1.21) (1.24) (2.64)** (0.84)

Arab Subject -0.231 -0.249 -0.013 0.084 (1.08) (1.20) (0.11) (0.88)

Asian Subject 0.470 0.469 -0.211 -0.392 (3.47)** (3.45)** (3.55)** (3.37)**

Indian Subject -0.241 -0.261 0.148 0.087 (1.99)* (2.25)* (1.50) (0.90)

Latino/a Subject -0.298 -0.303 0.196 0.285 (2.06)* (2.07)* (2.10)* (1.88)

Persian/Iranian -0.001 -0.001 -0.071 -0.039 Subject (0.01) (0.00) (1.04) (0.33)

0.136 0.149 -0.066 -0.018 Co-ethnic Pairing? (2.50)* (2.86)** (1.45) (0.33) -0.040 -0.013 0.098 African American

Respondent (0.49) (0.20) (1.13) Arab Respondent 0.096 -0.032 0.049

(0.90) (0.31) (0.34) Asian Respondent -0.014 0.029 0.015

(0.20) (0.55) (0.21) 0.123 -0.053 -0.009 Indian Respondent (1.10) (0.57) (0.09) 0.089 -0.138 -0.118 Latino/a Respondent (1.08) (2.65)** (1.80)

Persian/Iranian 0.224 -0.043 -0.129 Respondent (2.87)** (0.67) (1.67)

Observations 432 432 432 432 432 Table 7 Notes: Probit estimation, with marginal coefficient estimates (at mean values for the explanatory variables). Robust Z statistics are in parentheses. Significantly different than zero at 95% (*), 99% (**) confidence. Regression disturbance terms are clustered at the subject level. The omitted ethnic group category is Caucasian.

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Figure 1: Percentage of Viewings with Correct Identification, by Group and Level of Information

African Americans: Headshot

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14

average = 80.7%

perc

ent c

orre

ct

African Americans: Greeting w Name

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10 11 12 13 14

average = 82.7%

perc

ent c

orre

ct

Arabs: Headshot

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9

average = 26.1%

perc

ent c

orre

ct

Arabs: Greeting with Name

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9

average = 36.1%

perc

ent c

orre

ct

Asians: Headshot

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23

average = 95.1%

perc

ent c

orre

ct

Asians: Greeting with Name

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23

average = 92.8%

perc

ent c

orre

ct

Caucasians: Headshot

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

average = 84.4%

perc

ent c

orre

ct

Caucasians: Greeting with Name

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33

average = 84.2%

perc

ent c

orre

ct

44

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Figure 1 (cont’d): Percentage of Viewings with Correct Identification, by Group and Level of Information

Indians: Headshot

0

20

40

60

80

100

1 2 3 4 5

average = 44.7%

perc

ent c

orre

ct

Indians: Greeting with Name

0

20

40

60

80

100

1 2 3 4 5

average = 57.5%

perc

ent c

orre

ct

Latinos: Greeting with Name

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23

average = 73.3%

perc

ent c

orre

ct

Latinos: Headshot

0

20

40

60

80

100

1 3 5 7 9 11 13 15 17 19 21 23

average = 58.0%

perc

ent c

orre

ct

Persians/Iranians: Headshot

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10 11

average = 38.9%

perc

ent c

orre

ct

Persians/Iranians: Greeting with Name

0

20

40

60

80

100

1 2 3 4 5 6 7 8 9 10 11

average = 48.2%

perc

ent c

orre

ct

45

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Figure 2: Types of Misidentification

Subject is Latino/a Yes No

Yes

Correct Identification

False Positive

Respondent Identifies

Subject as Latino/a No

False Negative

Correct Identification

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APPENDIX A: INSTRUCTIONS FOR COLLECTION OF SIMULATION/DISSIMULATION IMAGES

Thank you for attending this extra session. You were one of the participants we selected

randomly for some additional image recordings. We will pay you $10 for your participation today.

As part of the experiment, we are interested in knowing whether people are able to guess the

ethnic backgrounds of people whose images they see. To help us to explore this issue, we would like to

make some extra recordings in which you actually state your ethnic background and try to convince other

people of it.

What is your ethnic background? _______________

First, we want to redo the three images we collected earlier. [RECORD HEADSHOT, VIDEO

WITH GREETING, VIDEO WITH GREETING AND NAME]

Now, we would like to make two recordings in which you try to convince the person who will

view the video clip that you are _______. Some people do this by saying something about where their

family is from; others use words from a language they know. You can say anything you think might be

helpful to convince others of your ethnic background. We will limit your recording to 20 seconds.

For the first recording, imagine that you are speaking to someone else who also describes

themselves as _______. What would you say to them to convince them that you are also _______? You

have 20 seconds. Take a moment, if you like, to think about what you would like to say. [RECORD IN-

GROUP SIMULATION VIDEO]

For the second video clip, think about what you might say to someone who does NOT self-

identify as _______ if you wanted to convince them that you are _______. You have 20 seconds. Again,

take a moment, if you like, to think about what you would like to say. [RECORD OUT-GROUP

SIMULATION VIDEO]

Now we will record a final video clip in which we will ask you to try to convince somebody that

you are NOT, in fact, _______. Imagine instead, that you want to convince the person who will view the

video clip that you are from any one of the ethnic groups on this list.

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African American

Arab

Asian

Caucasian

Indian

Persian/Iranian

Latino/a

If you wanted to convince the person that you were not _______ but from another ethnic group, which

group would you choose?

Now think about what you might say to convince the person that you are a member of this group.

You have 30 seconds. [RECORD DISSIMULATION VIDEO]

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49

APPENDIX B: INSTRUCTIONS FOR ETHNIC IDENTIFICATION GAME20

Welcome back to the Human Interaction Project. For your participation today, you will receive a

show-up fee of $5 along with whatever you win in the games you will play today.

Today you will be participating in a single game. The purpose of the game is to investigate how

well people are able to identify the ethnic backgrounds of the people they encounter in everyday life.

Lots of theories in political science, sociology, and other disciplines assume that individuals can readily

identify the ethnic backgrounds of the people they interact with. This experiment is designed to test

whether this is really the case.

To do this, we are going to show you a series of photographs and brief video clips of different

people and ask you to guess the ethnic backgrounds of the people you see.

In some of the video clips you will see, the person will actually tell you what their ethnic

background is. Recognizing that it is sometimes advantageous for people to try to “pass” as members of

groups other than their own, it is possible that some of the people may be lying about their ethnic

backgrounds. You should keep this in mind when you guess the backgrounds of the people whose images

you see. To earn the most money from this game, you will have to use your judgment to figure out when

people are telling the truth, and when they might be giving you false information.

First, you will be asked whether you know the person. Here we mean, do you know this

individual personally, outside of the context of this experiment. It is quite possible that you may have

20 The ethnic identification experiment described in this paper was part of a larger experiment, the results

of which are reported in Habyarimana et al. (2004). Subjects had therefore already participated in two

rounds of experimental games, and seen images of other subjects in the context of playing these games.

This was the first time, however, that they were made aware that the project sought to assess the effects of

ethnic group membership on their decision-making, and this was the first time that they were explicitly

asked to identify the ethnic backgrounds of other players.

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50

seen an image of this person before, as part of one of the earlier rounds of the experiment. Please only

indicate that you know the person if you have had a prior interaction with this individual in real life.

After viewing the picture of the person, you will be asked to guess the person’s ethnic identity

and to indicate your level of certainty about your guess.

You will see a series of three or four images of each person. Each image will provide you with

slightly more information about the person’s ethnic background. Each time, you will be asked to answer

the same questions. You should feel free to change your answers as you go along if the additional

information that you receive causes you to re-think your initial guess.

You will be paid 20 cents for each correct guess about the person’s ethnic identity. By “correct guess,”

we mean identifying the person in the same way that the person identified themselves to the

experimenters.