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TVJT : DISTRIBUTION OF SUBJECTS AS A FUNCTION OF AGE and YES RESPONSES. NUMBER OF TIMES CRITICAL STATEMENTS WERE ACCEPTED. Did the puppet say it WELL?. NELS 35. SCALAR IMPLICATURES IN CHILDREN: FAILURES OR SKILLFUL STRATEGIES?
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TVJT: DISTRIBUTION OF SUBJECTS AS A FUNCTION OF AGEandYESRESPONSES NUMBER OF TIMES CRITICAL STATEMENTS WERE ACCEPTED Did the puppet say it WELL? NELS 35 SCALAR IMPLICATURES IN CHILDREN: FAILURES OR SKILLFUL STRATEGIES? Francesca Foppolo & Maria Teresa Guasti - University of Milano-Bicocca For correspondance: francesca.foppolo@unimib.it SCALAR IMPLICATURES (SI): examples & derivation DO CHILDREN DERIVE SCALAR IMPLICATURES? • MECHANISM OF SI COMPUTATION (Chierchia, 2002) • SIs are part of the recursive interpretation of a sentence • For any expression with a scalar item, the strengthened • interpretation is computed by adding an implicature • (=negation of stronger alternatives)to its plain value • Plain/scalar value are compared • SI is adopted, only if it leads to a more informative statement A:Some linguists work in Milan B: Where do the other linguists work? some but not all linguists work in Milan C: Lyn has 2 children D: I think she wants athird Lyn hasexactly 2 children What is said [literal meaning]: SOME (= at least one), TWO (= at least two) What could have been said instead [alternatives]: ALL, THREE Scales: <some, all>; < n, (n+1)>, <, > where is informationally stronger than Make your contribution as informative as it’s required (Maxim of Quantity) What is conveyed [scalar implicature]: NOT ALL, NOT THREE 5 0 0 EXPERIMENT 1 - Guasti et al. (2004): Replication of Noveck (2001) Sentence Evaluation Task (SET): SOME ELEPHANTS HAVE TRUNKS Do you agree? Making the experimental goals clear Training: A friend of mine calls this AN ANIMAL BUT... there is a better way to describe it: THIS IS A PIG. Results: compare Fig.3 with Fig. 1&2 SET: DISTRIBUTION OF CHILDREN AFTER TRAINING • RESULTS 1 (SET) • CHILDREN (7 YEARS OLD) ARE MORE LOGICAL THAN ADULTS (Some = some even all) • TRAINING HAS AN EFFECT: CHILDREN BECOME LIKE ADULTS • ADULTS’ DERIVATION OF SI: 50% SET: DISTRIBUTION ADULTS (NO TRAINING) SET: DISTRIBUTION OF 7 YEAR-OLD-CHILDREN BEFORE TRAINING SET: DISTRIBUTION OF ADULTS(no training) DISTRIBUTION OF CHILDREN 15 15 10 5 0 15 10 5 0 S U B J E C T S S U B J E C T S S U B J E C T S 10 0 1 2 3 4 5 0 1 2 3 4 5 0 1 2 3 4 5 1 3 4 5 NUMBER OF TIMES CRITICAL STATEMENTS WERE ACCEPTED NUMBER OF TIMES CRITICAL STATEMENTS WERE ACCEPTED NUMBER OF TIMES CRITICAL STATEMENTS WERE ACCEPTED Fig. 3 Fig.2 Fig.1 EXPERIMENT 2 – Developmental study using the Truth Value Judgment Task Critical trial: an example Exp: What’s happening in the story? Puppet: SOME OF THE SMURFS ARE GOING ON A BOAT • RESULTS 2 (TVJT) • CHILDREN AT 6 & 7 DERIVE SI AS MUCH AS ADULTS: interestingly, adults’ & 7 year olds’ performance improved in this task: 9/19 adults & 16/18 children interpreted “some” logically in SET, while only 1/12 adults and 2/15 did so in TVJT • ONLY 50% OF THE CHILDREN AT 4 & 5 DERIVE SI: interestingly,they don’t behave at chance: half consistently accept, and half consistently reject the critical statements AGE & TASK affect subjects’ performance Subjects N. Age 15 7 12 6 12 5 12 4 12 Adults Material 5 critical stories 6 story-fillers Procedure Truth Value Judgement Task • CONCLUSIONS so far: • CRITICAL AGE FOR EMERGENCE OF SI: at 6 children are like adults, deriving SI “not all”; at 5 only half of the children are adult-like • TASK INFLUENCES SUBJECTS’ ANSWERS: more “logic” responses in children and adults if non natural setting • BIMODAL DISTRIBUTION OF SUBJECTS: subjects are consistent in their answers • CHILDREN PERFORMANCE DEPENDS ON SCALE: SI related to discrete scales emerge earlier PRAGMATIC FAILURES OR RESPONSE STRATEGIES ? Papafragou & Musolino (2004) – testing different scales 5 year old children – 3 scales: <some, all>, <two, three>, <start, finish> Derivation of SI by children: DISCRETE SCALE (65%) LOGIC SCALE (12,5%) ASPECTUAL SCALE (10%) Interestingly, subjects held a bimodal distribution: 6/10 always rejected the critical statements 3/10 always accepted them (1/10 behave at chance) SCALE matters TURN PAGE
A piece of Some (obj) Two Some (subj) The owl lighted up TWO candles False The dwarf picked up SOME OF the carrots Underinformative Baloo closed TWO bins True Batman bought SOME OF the pears True TWO clowns went fishing Underinformative ALL the soldiers rode a horse False ALL the monkeys had a biscuit True SOME OF the Smurfs went by boat Underinformative Which features of the experimental design adopted in all the experiments so far could have encouraged the use of a strategy in responding? • different groups of subjects were tested on different scales separately, so that each subject was tested on the same kind of statement 4 times in the course of the experiment (in P&M) • the critical stories had all the same underlying structure and the same outcome (some children remarked this similarity across stories, despite the presence of the fillers in between) • this fact could contribute to make the whole situation “artificial”, putting pragmatic norm aside RESULTS A different experimental design: BLOCKING STRATEGIES Subjects n. 40 5-year-old children (Age range: 4,11-5,11; Mean Age: 5,4; SD: ,15) n. 40 Adults control Materials 16 critical trials = underinformative statements containing different scalar items (in contexts that verify “three”, “all”, “whole” respectively): 4 items with TWO – like Two Smurfs went on a boat 8 items with SOME OF - 4 items like Some of the clowns went fishing 4 items like The dwarf picked up some of the carrots 4 items with A PIECE OF – like Cinderella decorated a piece of the tree 32 control trials - to check the understanding of the scalar items involved in the inference Procedure TVJT 4 conditions were created, 12 statements each: 8 control + 4 critical statements, one for scale 10 subjects were randomly assigned to each condition so that each subject was shown only one occurrence of each target item to avoid a parallelism across stories, the structure of the stories used to test different scales varied a lot, and the same initial structure was used to test different statements (with different outcomes) 1 characters + 3/5 objects 5 characters + 2 alternatives this allowed a greater variability of the material presented to each subject and a comparison of performance across different scalar items WITHIN the same subject • Significant effect of AGE (F(1, 78) =28.85, p<.0001) & ITEM (F(3, 234)=5.54, p<.001) and interaction among these factors (F(3, 234)=6.89, p<.0001) • Children derivation of SI: two=97,5% significantlyhigher than other items: a piece of = 62,5% (p=.0003) some (subj.) = 70% (p=.006); some (obj.) = 75% (p=.03) (difference between some subj./obj. position:n.s.) • Children performance on control items: above 92% for all the items except a piece of (p<.006): 80% correct • FINAL DISCUSSION • Individual variability across items indicate that subjects were answering according to the item, as they normally do in conversations, and not resorting to a strategy • The emergence of the ability in deriving SI is linked to the scalar item involved: different scales may be lexicalised at different stages in development • High performance on controls indicate that children know the scalar items: this is not enough for SI • Younger children are more sensible to the “anomalies” of the experimental setting and less ready to detect the “rules” of the game • INTERESTINGLY: • Subjects do not split in 2 groups anymore: not necessarily the answer given to the 1st scalar item is reiterated for the others • 5 year-olds performance with SI improve a lot in this experiment, compared to the results obtained by P&M with the same task (but different design): 65% vs 97,5% for TWO; 12% vs 72,5 % for SOME References Brain, M. and B. Roumain (1981). Children’s comprehension of “or”: Evidence for a sequence of competencies. Journal of Experimental Child Psychology 31:46-70.Chierchia, G., S. Crain, M. T. Guasti, A. Gualmini and L. Meroni (2001). The Acquisition of Disjunction: Evidence for a Grammatical View of Scalar Implicatures. In Proceedings of the 25th Boston University Conference on Language Development.Sommerville, Cascadilla Press. Chierchia, G. (2002) Scalar Implicatures, Polarity Phenomena, and the Syntax/Pragmatics Interface. Manuscript, University of Milan-BicoccaChierchia, G., M. T. Guasti, A. Gualmini, L. Meroni, S. Crain, F. Foppolo (2004). Semantic and pragmatic competence in children and adults’ comprehension of “or”. In Experimental Pragmatics, eds I.Noveck and D. Sperber, Palgrave. Crain, S. and R. Thornton (1998). Investigations in Universal Grammar. A Guide to Experiments on the Acquisition of Syntax and Semantics. The MIT Press, Cambridge, MA.808 Foppolo F., Guasti M. T., Chierchia G. (2004) Pragmatic inferences in children’s comprehension of scalar items. Talk presented at Second Lisbon Meeting on Language Acquisition Lisboa, 1-4 June 2004 Grice, P. (1975). Logic and Conversation. In P. Cole and J. Morgan (eds.) Syntax and Semantics 3: Speech Acts. Academic Press, New York. Grice, P. (1989) Studies in the Way of Words. Harvard University Press, Cambridge, MA.Guasti M. T., Foppolo F., Chierchia G. (2004) (in prep.) Scalar Implicatures in Child Language: failures or skilful strategies? Guasti M. T., Chierchia G., Foppolo F., Gualmini A., Meroni L.(2004) Why Children and Adults Sometimes (but not always) Compute Implicatures.To appear in Language and Cognitive Processes Guasti M. T. (2002) Language Acquisition. The Growth of Grammar. MIT Press. Cambridge, MA.Hirschberg, J. (1985). A Theory of Scalar Implicatures. Doctoral dissertation, University of Pennsylvania, Philadelphia, PA.Horn, L. (1972). On the Semantic Properties of Logical Operators in English. Doctoral Dissertation, UCLA, CA. Levinson, S. (2000) Presumptive meaning. Cambridge, MA :MIT Press. Noveck, I. (2001). When children are more logical than adults: Experimental investigations of scalar implicatures. Cognition, 78, 165-188.Papafragou A. and J. Musolino (2003) Scalar Implicatures at the Semantic-Pragmatics Interface. Cognition, 80, 253-282.Smith C. L. (1980) Quantifier and question answering in young children. Journal of Experimental Child Psychology, 30:191-205. e-mail: francesca.foppolo@unimib.it NELS 35 - Storrs, Oct22-24 2004