chapter seven: the basics of experimentation ii: final considerations, unanticipated influences, and...

Chapter Seven:The Basics of Experimentation II:Final Considerations, Unanticipated Influences, and Cross-Cultural Issues

Participants Types of participants


Three guidelines to help you choose participants for your research project:



Precedent



Precedent Availability



Precedent Availability Nature of the Problem

Types of participants Precedent

An established pattern

Types of participants Precedent

An established pattern If your literature review indicated that a particular type of

participant has been used successfully in prior research projects in your area of interest, they you may want to consider using this type of participant.

Types of participants Availability

Types of participants Availability

Availability refers to using an easily accessible population from which to draw participants.

Types of participants Type of Research Project

Types of participants Type of Research Project

Often the type of research project will determine the type

of participant you decide to use.

Number of Participants Once you have decided what type of participant to use

in your research project, you must then determine how many participants you are going to test.



In making this decision, there are numerous factors that you must take into account:



In making this decision, there are numerous factors that you must take into account:

Finances

Number of Participants In making this decision, there are numerous factors that

you must take into account: Finances


you must take into account: Finances Time


you must take into account: Finances Time Availability

Number of Participants Finances


How much will it cost to test each participant?


How much will it cost to test each participant? Animals need to be purchased and cared for.


How much will it cost to test each participant? Animals need to be purchased and cared for. It may be necessary to pay humans for their

participation.


How much will it cost to test each participant? Animals need to be purchased and cared for. It may be necessary to pay humans for their

participation. Does the person who actually conducts the experiment

need to be paid?

Number of Participants Time

Number of Participants Time

As you test additional participants, time requirements will increase, especially if you test participants individually.

Number of Participants Availability


The sheer number of participants that are available may influence how many you choose in your experiment.



The less within-group variability (i.e., the more homogeneous the participants), the fewer participants we will need.



The less within-group variability (i.e., the more homogeneous the participants), the fewer participants we will need.

The greater the within-group variability (i.e., the more heterogeneous the participants), the greater the number of participants we will need.

Number of Participants Power


The number of participants tested is related to the power of our statistical test.


The number of participants tested is related to the power of our statistical test.

Power is the probability that a statistical test will be significant (i.e., the experimental hypothesis is accepted when it is true).

Apparatus IV presentation

Apparatus IV presentation

Often the nature of the IV will influence the type of apparatus one chooses to use.

Apparatus IV presentation DV recording


How the DV will be recorded:


How the DV will be recorded: Use of a prepared data sheet in a naturalistic

observation study


How the DV will be recorded: Use of a prepared data sheet in a naturalistic

observation study Use of video recording equipment when its presence

will not cause reactivity effects.

The Experimenter as an Extraneous Variable Experimenter Characteristics

Experimenter Characteristics Physiological


Characteristics such as age, sex, and race can have an influence on participants’ responses.



Psychological



Psychological Characteristics such as hostility, anxiety, introversion or

extraversion can also have an influence on participants’ responses.

Experimenter Expectancies Experimenter expectancies are expectations that cause

him/her to behave toward participants in such a manner that the expected response is, indeed, more likely shown.

Experimenter Expectancies Rosenthal effect


The experimenter’s preconceived idea of appropriate responding influences the treatment of participants and their behavior.


The experimenter’s preconceived idea of appropriate responding influences the treatment of participants and their behavior.

The results of experimenter expectations are often called Rosenthal effects because Rosenthal and his colleagues were among the first to systematically study them.

Controlling Experimenter Effects Physiological and Psychological Effects


At present the most common procedures for controlling general experimenter characteristics are to:



Use standardized methods



Use standardized methods Use careful training to a set standard when the

experimenter administers procedures



Use standardized methods Use careful training to a set standard when the

experimenter administers procedures Standardize appearance, attitude, and so forth as much

as possible.


If findings are replicated with a different experimenter, then experimenter effects are less likely to be a factor.


If findings are replicated with a different experimenter, then experimenter effects are less likely to be a factor.

A thorough literature review will help make you aware of any relevant experimenter variables in your area of research interest.

Controlling Experimenter Effects Experimenter Expectancies


The instructions that the experimenter gives to the participants should be carefully prepared so their manner of presentation will not influence the participants’ responses.


The instructions that the experimenter gives to the participants should be carefully prepared so their manner of presentation will not influence the participants’ responses.

Any instructions concerning scoring the participants’ responses should be as objective and concrete as possible and established before the experiment is started.


Instrumentation and Automation


Instrumentation and Automation Tape-record experimenter instructions to participants


Instrumentation and Automation Tape-record experimenter instructions to participants Printed instructions


Instrumentation and Automation Tape-record experimenter instructions to participants Printed instructions Computer displays


Instrumentation and Automation Tape-record experimenter instructions to participants Printed instructions Computer displays

Automated equipment can ensure the accurate recording and storage of response data.

Controlling Experimenter Effects Single-blind experiment

Controlling Experimenter Effects Single-blind experiment

The experimenter has no knowledge regarding which participants receive which treatment(s).

Participant Perceptions as Extraneous Variables Demand characteristics


Features of the experiment that inadvertently lead participants to respond in a particular manner.


Features of the experiment that inadvertently lead participants to respond in a particular manner.

Participants in psychological research may attempt to figure out how they are supposed to respond and then behave in this manner.

Participant Perceptions as Extraneous Variables Demand characteristics Good participant effect

Participant Perceptions as Extraneous Variables Demand characteristics Good participant effect

The tendency of participants to behave as they perceive the experimenter wants them to behave.

Participant Perceptions as Extraneous Variables Response Bias


Yea-sayers


Yea-sayers Participants who tend to answer yes to all questions.



Nay-sayers



Nay-sayers Participants who tend to answer no to all questions.

Participant Perceptions as Extraneous Variables Response set

Participant Perceptions as Extraneous Variables Response set

The experimental context or testing situation influences the participants’ responses.

Controlling Participant Effects Demand Characteristics


We can conduct an experiment in which both the experimenter and the participants are unaware of which treatment is being administered to which participants.


We can conduct an experiment in which both the experimenter and the participants are unaware of which treatment is being administered to which participants. Such experiments are known as double-blind experiments.

Controlling Participant Effects Yea-saying

Controlling Participant Effects Yea-saying

The most typical control for yea-saying (and nay-saying) is to rewrite some of the items so that a negative response represents agreement (control for yea-saying) or a positive response represents disagreement (control for nay-saying).

Controlling Participant Effects Response Set


The best safeguard against response set is to review all questions that are asked or items to be completed to see if a socially desired response is implied in any manner.


The best safeguard against response set is to review all questions that are asked or items to be completed to see if a socially desired response is implied in any manner.

The answer given or response made should reflect the participant’s own feelings, attitudes, or motives rather than an attempt to appear intelligent or well-adjusted or otherwise “normal.”

The Interface Between Research and Culture Culture

The Interface Between Research and Culture Culture

Lasting values, attitudes, and behaviors that are shared by a group and transmitted to subsequent generations.

The Interface Between Research and Culture Cross-cultural psychology

The Interface Between Research and Culture Cross-cultural psychology

A branch of psychology whose goal is to determine the universality of research results.

The Interface Between Research and Culture Culture, Knowledge, and Truth


Etic


Etic A finding that is the same in different cultures.


Etic A finding that is the same in different cultures. Represents an absolute truth.



Emic



Emic A culture-specific finding



Emic A culture-specific finding Represents a truth relative to a specific culture.

The Interface Between Research and Culture Ethnocentric


Other cultures are viewed as an extension of one’s own culture.


Other cultures are viewed as an extension of one’s own culture.

If other cultures are viewed as an extension of one’s own, the result may be research findings that cannot be generalized beyond one’s own culture.

The Effect of Culture on Research Choice of the Research Problem


In some cases there may be no doubt that the choice of your research problem is culture dependent.


In some cases there may be no doubt that the choice of your research problem is culture dependent.

For example, studying the nature of a crowd at a rock concert.

The Effect of Culture on Research Choice of the Research Problem Nature of the Experimental Hypothesis


Cultural differences may lead to different experimental hypotheses.


Cultural differences may lead to different experimental hypotheses.

For example, studies of personal space.

The Effect of Culture on Research Choice of the Research Problem Nature of the Experimental Hypothesis Selection of the IV and the DV

The Effect of Culture on Research Choice of the Research Problem Nature of the Experimental Hypothesis Selection of the IV and the DV

For example, IV presentation and DV measurement may be accomplished by computer in technologically advanced cultures but not in cultures unfamiliar with computers.

Methodology and Analysis Issues Participants and Sampling Procedures


The basic question here is whether the sample of participants is representative of the culture from which they were drawn.


The basic question here is whether the sample of participants is representative of the culture from which they were drawn.

For example, extreme differences may exist between samples drawn from large urban centers and those drawn from rural areas.

Methodology and Analysis Issues Participants and Sampling Procedures Type of Survey or Questionnaire Used

Methodology and Analysis Issues Participants and Sampling Procedures Type of Survey or Questionnaire Used

Although an existing survey or questionnaire may work in a few instances, most likely the researcher will not be able to use it for research in a different culture.

Methodology and Analysis Issues Participants and Sampling Procedures Type of Survey or Questionnaire Used Cultural Response Set


A cultural response set is the tendency of a particular culture to respond in a certain manner.


A cultural response set is the tendency of a particular culture to respond in a certain manner.

If differences exist among the groups tested in various cultures, a cultural response set may be operating.

chapter seven: the basics of experimentation ii: final considerations, unanticipated influences, and...

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