semantic indeterminacy in object relative clauses maryellen c. macdonald silvia p. gennari

Semantic indeterminacy in object relative clauses

Maryellen C. MacDonald Silvia P. Gennari

Introduction-Sentence Comprehension Research

Temporary syntactic ambiguity:“the man examined by the doctor”.

Vs.

Syntactically complex unambiguous structures:“the man that the doctor examined”. (ORC)

Introduction - Sentence Comprehension research

2 accounts:

1. The ambiguity resolution literature-debate between 2 approaches: (1) two-stage

(2) Constraint-based

Two stageinitial analysis + reanalysis Example: “the man examined by the doctor”

Comprehension difficulty: complexity of the reanalysis process.


Constraint-based approach (MacDonald et al 1994)

Alternative interpretations are partially activated due to certain constraints (frequency, plausibility etc).

Comprehension difficulty: competition between the interpretations.


2. The syntactic complexity literature -focus on : memory demands, thematic role

assignments, etc.In principal: ambiguity resolution mechanisms are

different from complex unambiguous structures, such as object relative clauses.

Traxler, Morris and Seely (2002) attempt


Two stage process of temporary ambiguous “that”:“the man that…” (ambiguous: either Sub.Rel or Obj.Rel)“the man that the…” (unambiguous: only Obj.Rel)

1. Trivial ambiguity2. No constraint-based approach involved !

So, is there a link between ambiguity resolution literature and complex syntactic structures after all?


Focus of this paperConnecting between complexity and ambiguity

resolution by asking:(1) Is constraint-based approach relevant to object

relative clauses research?

Does activation of competing interpretations can account for comprehension difficulty?

(2) Do object relative clauses present semantic indeterminacy as they unfold?

Processing difficulty in Object Relative Clauses

1. Contrasting object relatives and subject relatives(King and Just 1991):

a. Subject relative: “the reporter that attacked the senator admitted the error”.

b. Object relative: “the reporter that the senator attacked admitted the error”.

Which is harder to comprehend?


Similarity: words, number. Difference: word-order, final sentence meaning• Conflicting thematic roles Sheldon (1974):

Obj.Rel: "reporter” is simultaneously the AGENT of "admitted" and PATIENT of "attacked" extra burden.Subj.Rel: “reporter” is the agent of both verbs simpler meaning.

• Two un-integrated nouns-Obj.Rel: ("the reporter that the senator") before the verb memory loadSubj.Rel: alternating nouns and verbs (“the reporter that attacked the senator admitted the error”) rapid integration


• Noun referential properties (Gordon et.al 2001)Indexical expressions : "I"/"you"/proper names at the embedded subject position"the reporter that I attacked" reduces memory load

Vs.Descriptive NP'S ("the senator") increase memory load

In contrast


• Noun animacy (Mak et al. 2002)-a) The director that watched the movie received a prize. (Subj. Rel. -

Animate head)

b) The director that the movie pleased received a prize. (Obj. Rel. – Animate head)

c) The movie that pleased the director received a prize. (Subj. Rel. – Inanimate head)

d) The movie that the director watched received a prize. (Obj. Rel. – Inanimate head)


Constraint-based approach In ambiguity resolution literature-Trueswell et al. (1994): Noun animacy and its

semantic fit (theta-roles) had immediate effects on processing difficulty.

Constraint based approach need not only operate in ambiguous structures!

Semantic and syntactic indeterminacies may emerge from the activation of several alternative structures, in complex structures.


Comprehension difficulty in object relatives may emerge from the activation of several competing interpretations.

How many interpretations are there?Which of them are preferred over others?

Determined by language use: such as noun animacy configurations and thematic fit.


For example:

Different animacy configurations different competition processes between structural and semantic analyses different levels of indeterminacy and difficulty.

Different animacy configurations different competition processes between structural and semantic analyses different levels of indeterminacy and difficulty.

“The movie that the director…” “The director that the movie…”

“wrote”Theta roles: AGENT, THEME

“was written by”Theta-roles: AGENT, THEME

---- “was given to”Theta-roles: GOAL, THEME

---- “pleased”Theta-roles: CAUSE, EXPERIENCER

Current study: Testing indeterminacy in object relative clauses

Three studies:1. Gated sentence completions - in order to

assess which alternative interpretations are dominant as the sentence unfolds.

2. Self-paced reading- comparing reading times in object relatives to an unambiguous control condition, passive relatives.

3. Predicting reading time- relating completion data (study 1) and reading data (study 2)

Study 1: Gated sentence completions

Study 1: Gated sentence completions

This study investigates which interpretations speakers entertain at several points within object relative clauses of varying noun animacy.

• Animate/inanimate head clauses• Completion tasks at several positions:

1. “The N that…”2. “The N that the…”3. “The N that the N…”4. Passive: “The N that was Ved”

Study 1- gated sentence completion

Why a passive prompt?Because nouns animacy and thematic roles are

the same in Obj.Rel clauses and in passive relatives. Thus they provide a good control condition.

Example:“The director that the movie pleased” “The director that was pleased” (passive relative)

Study 1- Expectations

1. Noun animacy would play a critical role in determining which interpretation is entertained by the reader.

2. Since animate nouns can play more roles in an event active animate-heads would show more indeterminacy than inanimate ones.

3. Active Obj.Rel would differ than passive ones,and show greater indeterminacy because of later verb appearance.

Study 1 - MethodsParticipants: 64 students of University of Wisconsin-Madison. 16 per each of the 4

questionnaires. 8 per each list.Material: Traxler et al.’s (2002)

-4 positions/conditions = 4 questionnaires-Fillers

Study 1 – Completions coding

According to1. Syntactic structure - NP’S, VP’S, PP’S (and their order)Example: “the movie that [I saw]” np-v2. Thematic role: (Haegeman, 1991, and Belletti and Rizzi,

1988,Dowty 1991)Agent (including institutional actors i.e. “school”)Patient (affected participants)Theme (moving objects)Experiencer (of a certain state)Goal (directed participants)Location (times or places)

Study 1 – Results

Study 1 – Results:1. Completions at “The N that”…

(1) subject relatives(2) object relatives

Thematic role Structure Animacy

Agents, Experiencers Sub.Rel: 85%Obj.Rel: 15%

Animate heads(“the director that...”)

Themes

Second role: agent

Sub.Rel: 35%Obj.Rel: 65%

Inanimate heads(“the movie that…”)

Study 1- Results1. Completions at “the N that”…

• Animate agents are preferred in the subject position within the object relative clause. (i.e “the movie that the director.....”)

Overall: animate and inanimate nouns are each

associated with distinct thematic roles and structures.

Study 1-Results 2. Completions at “The N that the…”

All completions were in the format of object relative clauses (presence of “the”)-

• Animate heads were either:- patients of agent-patient verbs (hire, expel)- themes of experiencer-theme verbs (see, like)

Ex:“The employee that the manager hired/liked.”

• Inanimate heads were always themes.Ex:

“The movie that the director made”.

Study 1- Results 2. Completions at “The N that the”

• There were more alternative interpretations (=indeterminacy) in the animate-head condition.

• For both animate and inanimate heads there was an animate noun in the subject position of the relative clause.

Overall: the set of noun and role choices was perceived as more constrained.

Study 1- Results 3. Completions at “The N that the N”…

• Inanimate-animate configurations-(“the movie that the director”) were mostly completed with a single relative clause verb (“wrote”).Thematic roles: Theme head-noun, Agent for the RC subject.

• Animate heads (“the director that the movie”) showed a variety of equally likely verb phrases and thematic roles.

Table 3

Study 1- Results3. Completions at “The N that the N”…

Overall:Marked differences across conditions• Animate-inanimate configurations - greater

indeterminacy regarding thematic roles, VP structures etc.

• Inanimate-animate configurations – mostly the same syntactic and semantic analysis.

Study 1- 4. Passive completions at “the N that was V”

Similar results across animacy conditions 70% - completed with a main sentential verb.30% - completed with by-phrases and prepositional

phrases.Overall:• Little indeterminacy with passives compared to

active object relative clauses (with same number of words).

• Passive relatives are perceived as already complete (even though the agent/cause role is missing).

Study 1 - Discussion

1. Animacy does play a role in determining available alternative interpretations.

2. Animate-head active object relatives show greater indeterminacy than inanimate-heads. (particularly at “the N that the N”)

3. Object relative clause subject position prefers animate entities.

4. Thematic roles: Inanimate nouns= Theme Animate nouns= Agent/Experiencer5. Passive relatives had more restricted analysis than active

ones. (less available interpretations).

Study 2 – Reading comprehension

This study examines reading time patterns in comprehending Obj.Rel clauses of different animacy, to evaluate the constraint-based hypothesis from study 1:

comprehension difficulty is due to competition among alternative

interpretations, and the degree of indeterminacy as the relative clause unfolds .

Study 2 - Expectations

1. More comprehension difficulty for active compared to passives (particularly at the position of the verb).

2. More comprehension difficulty with animate-head active clauses than in inanimate ones, particularly in 2 critical positions:- the relative clause subject.- the relative clause verb.

Study 2 – inconsistency between study 1 completions and the material

Material (Traxler et.al 2002)

Study 1 - completions

Animate-heads co-occur with inanimate relative clause subjects .(“the director that the movie”)

Tendency to use animate nouns.

Animacy choice in relative clause subject position.

Cause-Experiencer verbs, such as please, amuse, annoy. (“the director that the movie pleased”)

Agent-Theme verbs.

(“the student that the teacher suspended”)

thematic roles of animate-heads in the RC verb position.

Study 2- Methods

Participants: 63 native-English students (Wisconsin Uni.)Materials: 28 items – 4 versions each. Example of an item of reading:

1a) The musician that the accident terrified was in the headlines the next day. (active-animate)

1b) The accident that the musician caused was in the headlines the next day. (active-inanimate)

1c) The musician that was terrified by the accident was in the headlines the next day. (passive-animate)

1d) The accident that was caused by the musician was in the headlines the next day. (passive-inanimate)

Study 2- Methods

• Materials: verbs and nouns were matched for frequency and word-length.

• Procedure: word-by-word self-paced reading paradigm + Comprehension question

• Residual reading time calculation

Subject’s reading time

per wordWord length

Residual reading

time

Study 2- Comprehension responsesResults

Table 5 RC condition Mean SD

Active – Animate head .69 .25 Active – Inanimate head .84 .20 Passive – Animate head .81 .18 Passive – Inanimate head .84 .16

Study 2 - Results

Overall: 1. Animate-heads were more difficult than

inanimate ones. (mainly with actives)2. Active object relatives were more difficult

than passives, mainly because of low correct responses to active animate-head relatives.

Study 2 - Reading time results1. Animate heads are more

difficult than inanimate ones.

2. Animate-heads are more difficult than both

inanimate and animate-head passives.

3. Inanimate heads did not differ from passives.

Both active conditions had longer reading times than any passive condition.

1. Passives did not differ themselves.

2. At the main -ed verb: Inanimate-heads only

differed from inanimate-head passives.

(same for the other 2 points)

Study 2 - discussion

• Animate-head object relatives are more difficult to process than inanimate ones.

• Points of highest difficulty:(1) RC subject - earliest possible point. Significance only with animate-heads.(2) RC verb- animate-head condition was most difficult . (in agreement with “the N that the N” completions).

• Inanimate-heads differed from passives most at the verb positions.

Study 3 – Predicting reading times

This study examines whether the preferred interpretations of study 1, predict reading times at each position of the relative clause.

How? 1. Proportional measures: 2. Non-proportional measures:

By regressing the proportion of interpretations from study 1, at different positions, onto the reading time of subsequent positions from study 2.

Rationale :The more likely an interpretation, the less competition, and less difficulty to activate. (and vice versa).

By regressing :- number of thematic role interpretations at each point.- number of verbs.

Rationale :The more interpretations or verbs provided for a given item, the more competition. (and vice versa)

Study 3 – Expectations

1. Frequency distribution of preferred interpretations:

“The N that…” and “The N that the…” “The N that the N” subsequent verbs2. Semantic Vs. syntactic measures:Thematic completions would account for more variance than syntactic alternatives. why?

Study 3 - Expectations

• Thematic roles and animacy at a certain position would be better predictors of reading times at the subsequent position:Mostly in: -RC subject position -verbs positions

3. Active and passive reading times should be predicted by their varying degrees of semantic indeterminacy at all relevant positions.

Study 3 - Procedure

3 different measures:1. Syntactic structure2. Thematic role3. Animacy For each positionProportion of completions consistent with the

“correct” analysis in the material (traxler et.al 2002).

Study 3 - Procedure

1. Syntactically-completions into the-N-verb structure were considered “correct”. (“the director that the movie pleased”).

For both animate and inanimate head relatives• “the N that..” = np-vp• “the N that the…” = np-v• etc •

Study 3 - Procedure

2. Thematically-Closest in meaning to the material. (traxler 2002)Inanimate head nouns Animate head

nouns

Theme followed by agent/experiencer

Exp’/patient/goalfollowed by agent/cause.

“The N that…”

“The N that the…”


Experiencer-causeExperiencer-theme

“The N that the N”


Experiencer/patient followed by agent/cause/adjs

Passives

Study 3 - Procedure

Non-proportional measures-1. The number of alternative thematic role

interpretations for each point.Example: “the-N-that-the N” received either theme-agent interpretations or theme-experiencer ones 2 alt.int in total.

2. The number of verbs usedExample: “the director that the movie…” had a certain verb completion (“was written by”..)

• An index of the number of interpretations.• More verbs for animate entities.

Study 3 - Results

Active object relative clauses:Table 7

Study 3 - Results

“The N that the…” - was predicted at the previous 2 positions (“the N that”+”the N that the”) by:

-the proportion of “correct” animacy completions.

-the proportions of “correct” syntactic.-the proportion of "correct" thematic

interpretations.

How will we know if semantic predictors increased the variance significantly? By a multiple regression model

Example: ”A regression model with only the structurally

“correct” analyses at the-N-that accounted for 38% of the variance, whereas the addition of the number of alternative interpretations at the-N-that-the into the regression model increased the variance to 56%, a significant increase”.

Study 3 - Results

Examples of scatter plots for different predictors at the different word positions in Study 3

Structure completions proportion at “the N that”

Thematic proportion at “the N that the”

Number of interpretations at “the N that the”

Number of verbs at “the N that the N”

Structure proportion at “the N that the N”

Thematic proportion at “the N that the N”

Study 3 - Results

Main aux verb- The proportion of “correct” thematic roles at the the-N-that-the-N position was a better predictor than the structural count.

The main verb-the thematic role count at position the-N-that-the-N was the best predictor.

Active and passives-the proportion of correct thematic interpretations in the completions predicted longer reading times in active and passive structures.

Study 3 - discussion

• “Correct” completions predicted comprehension difficulty at subsequent positions.

• Semantic measures were stronger predictors than structural measures at all positions, and both in passives and actives.

• At verb positions, activation of correct interpretations was slower and competition stronger.

• Thematic roles were stronger predictors than animacy.

The degree of competition between

alternative interpretations (semantic information) substantially contributes to the degree of comprehension difficulty, thus explaining differences across relative clause types.

Study 4

Just kidding…

Thanks for listening!

semantic indeterminacy in object relative clauses maryellen c. macdonald silvia p. gennari

Documents

object relative clauses1

doctorcomprehension

contrasting object relatives

complex unambiguous

complex syntactic structures

relthe man

memory demands

memory load vs