Ling 240: Language and Mind Structure Dependence in Grammar Formation TWO HYPOTHESES ABOUT YES/NO QUESTIONS How do we form yes/no Qs? a. The man is tall. Is the man tall? b. The book is on the table. Is the book on the table? c. I can go. Can I go? Move the first Aux Move the first Aux The ordinal order of X is determined by position in a sequence => a structure independent A structure independent rule ignores higher-order structural units, relying only on linear order Does ‘Move the first Aux’ rule work? ‘Move the first Aux’ rule doesn’t work when there is more than one Aux (1) The man who is tall is in the other room. which becomes: (2) *Is the man who ___ tall is in the other room? (3) Is the man who is tall ___ in the other room? Structure Dependent the correct hypothesis must therefore recognize the internal structure of sentences Move the highest Aux The height of X is determined by the number of nodes that dominate X => structure dependent UG narrows down the hypotheses space Input is compatible with infinite number of hypotheses Claim: Innate principles (and parameters) guide learning (Universal Grammar) Prediction: children will not make types of errors that violate UG principles Summary: Adult Mental Grammar of English Rule: Move the highest Aux. Mental Grammar only allows the structuredependent version of the rule. What do kids do? What types of mistakes do they make? (Crain & Nakayama 1987) Do children ever consider “move the first” rule? Null hypothesis: children do not have innate grammatical knowledge that makes them ignore structure-independent rules. Prediction: children should consider the “move the first” rule, because the rule is simple, concrete and perfectly compatible with their experience. Crain and Nakayama 1987 “Elicited production” experiment Participants: English-speaking children (N=30, Age: 3;2 – 5;11) Group 1: 3;2 – 4;7 (Mean 4;3) Group 2: 4;7 – 5;11 (Mean 5;11) Hey Tommy, look at this! Look at this picture! Tommy Experimenter Jabba the Hutt Tommy, do you think the girl is tall? Experimenter Tommy Jabba the Hutt Experimenter Noooo! She is not tall! Tommy Jabba the Hutt Yeah I agree…but I wonder what Jabba would say… Tommy Experimenter Jabba the Hutt Hey Tommy, why don’t you ask Jabba if the girl is tall? Ask Jabba if the girl is tall! Tommy Experimenter Jabba the Hutt Experimenter Is the girl tall? Tommy Jabba the Hutt Experimenter No… Tommy Jabba the Hutt He was right! Tommy, give him a strawberry! Tommy Experimenter Jabba the Hutt Materials Pretest sentences: to ensure that children understood the task and could form simple yes/no questions. a. The girl is tall b. The man is tired c. The pig next to the tree is red Materials Test sentences a. b. c. d. e. f. [The dog that is sleeping] is on the blue bench. [The ball that the girl is sitting on] is big. [The boy who is watching Mickey Mouse] is happy. [The boy who is unhappy] is watching Mickey Mouse. [The boy who is being kissed by his mother] is happy. [The boy who was holding the plate] is crying. “Ungrammatical” questions We are interested in whether children consider the “move the first” rule… *Was the boy who __ watching TV is crying? structure-independent, or “TYPE III” error “Ungrammatical” questions “Good” results would be If children never made any ungrammatical questions at all. Even stronger results would be: If children made various ungrammatical questions, but they never made TYPE III errors. Results I: did they make ungrammatical questions? YES. Group I Group II Total 81 87 168 Grammatical 31 (38%) 70 (80%) 101 (60%) Ungrammatical 50 (62%) 17 (20%) 67 (40%) Are there any Type III (structureindependent) errors? Was the boy who __ watching TV is crying? Group I Group II Type I 30(60%) 9 (53%) Type II 10 (20%) 5 (29%) Type III 0 0 Type I = extra Aux. Is the boy who is watching TV is happy? Type II Restart. *Is the boy who is watching TV, is he happy? *Was the boy who __ watching TV is crying? structure-independent, or “TYPE III” error Children never made Type III errors. suggests that they never consider structure-independent movement rules: “move the first…”. Do children ever consider “move the first” rule? Null hypothesis: children do not have innate grammatical knowledge that makes them ignore structure-independent rules. Prediction: children should consider the “move the first” rule, because the rule is simple and perfectly compatible with their experience. Remaining question Could they get the right pattern from input directed to them? (Legate & Yang 2002) The CHILDES database A huge database of spontaneous speech by young children (age 2 – 6) Transcriptions of parent-child linguistic interactions What kinds of questions do children hear from adults? Legate and Yang (2002) Child: Adam (2;7 - ) Total parental utterances: Number of questions: The crucial sentences: 46,499 20,651 0 Child-directed speech does not involve the crucial data Is John happy? is = the first, and the highest Is the boy who was watching TV crying? is = NOT the first, but the highest So… Input directed to children does not involve the crucial data to distinguish “move the first Aux” from “move the highest Aux” Therefore, the input does not tell children that “move the first” is wrong. Innate linguistic knowledge /UG (Universal Grammar) UG restricts the range of possible rules that children consider in the course of language acquisition