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Psy1302 Psy1302 Psychology of Psychology of LanguageLanguage
Language Acquisition IILanguage Acquisition II
Lecture 18Lecture 18
Reading AssignmentReading Assignment
Fisher & Gleitman (2002)Fisher & Gleitman (2002) I. Outline of the task of language learningI. Outline of the task of language learning II. Where language learning beginsII. Where language learning begins
– Categorization of Speech SoundsCategorization of Speech Sounds– Segmentation of Spoken WordSegmentation of Spoken Word– Role of Sound in Syntactic AnalysisRole of Sound in Syntactic Analysis– Distributional Analysis and Discovery of SyntaxDistributional Analysis and Discovery of Syntax
II. MeaningsII. Meanings– Primitive Categories of ExperiencePrimitive Categories of Experience– Compositional MeaningCompositional Meaning– Interactions between linguistic and conceptual categoriesInteractions between linguistic and conceptual categories
IV. Forms to meaningIV. Forms to meaning– Mapping problemMapping problem– Concrete words firstConcrete words first– Old words make new words easier to learnOld words make new words easier to learn
V. Where learning endsV. Where learning ends
What does What does ““tokibu tokibu gikoba gikoba gopila gopila tipolutipolu”
mean anyway?mean anyway?
Mapping Form to Mapping Form to MeaningMeaning
To learn a language is, by definition, to acquire a set of pairings between sounds or more abstract linguistic structures and their meanings.
Fisher & Gleitman (2002)
Artist: Henry Gleitman
Elephant!
Learning by Learning by AssociationAssociation
John Locke, 1690 Book 3, IX, 9:
If we will observe how children learn languages we shall find that .... people ordinarily show them the thing....and then repeat to them the name
You learn the meaning of elephant because You learn the meaning of elephant because whenever you hear “elephant” you see an elephant. whenever you hear “elephant” you see an elephant.
Association is formedAssociation is formed Of course often you see other things as well...Of course often you see other things as well...
Learning by Learning by AssociationAssociation
Gavagai!
Unconstrained inductionUnconstrained induction(or the radical indeterminacy of (or the radical indeterminacy of translation)translation)
Quine, 1960Quine, 1960
What could What could “gavagai” mean?“gavagai” mean?
Rabbit?Mammal?
Ears?
Brown?Fluffy?
Carrot eater?
ScurryingHopping
Thumping
Stay!
What a cutie!
Meal!Rabbit only until eaten!
That’s not a dog!
Chinchila rabbit?
Animal?
vegetarian?
Long ears?
Look!
Unconstrained inductionUnconstrained induction
RABBIT!
RABBIT
EAR and PAW
RABBIT
+ FLOOR
Sometimes I wonder
too!
Learning by Learning by AssociationAssociationPROBLEMSPROBLEMS1. Relying on Association could be 1. Relying on Association could be
slowslow– Have to rule out many alternate Have to rule out many alternate
hypotheseshypotheses– Yet, children sometimes learn words Yet, children sometimes learn words
in a single trial.in a single trial.
“Give me the chromium tray, not the blue tray.”Fast Mapping Carey & Bartlett
Learning by Learning by AssociationAssociationPROBLEMSPROBLEMS2. Some meanings cannot be 2. Some meanings cannot be
disentangled from situationsdisentangled from situations
GIVING RECEIVING
VERBS
PREPOSITIONS
ABOVE
BELOW
Learning by Learning by AssociationAssociationPROBLEMSPROBLEMS3. How do we learn words that do 3. How do we learn words that do
not refer to concrete objects?not refer to concrete objects?– ““nap”, “hour”nap”, “hour”– mental states: e.g. “think”mental states: e.g. “think”
Learning by Learning by AssociationAssociationPROBLEMSPROBLEMS4. We do not always see object or 4. We do not always see object or
action at the same time as we action at the same time as we hear the word.hear the word.
– “– “Where’s your mother?”Where’s your mother?”
– “– “Eat your peas”Eat your peas”
– – OPENING action occurs only 1/3 of OPENING action occurs only 1/3 of the times that “open” saidthe times that “open” said
Learning by Learning by AssociationAssociationPROBLEMSPROBLEMS5. Does not necessarily explain 5. Does not necessarily explain
how we learn to generalize word how we learn to generalize word to new instancesto new instances
– An object can be categorized at many levelsAn object can be categorized at many levels– And in many ways (by shape, size, texture, And in many ways (by shape, size, texture,
function)function)
ChairsChairs
http://en.wikipedia.org/wiki/List_of_chairs
Child sees only a few exemplars of dog....how does she learn to extend the word to all these different types of dogs?
Given all the above problems with Given all the above problems with the the learning by associationlearning by association account…account…
How do children ever learn the How do children ever learn the mappings between form and mappings between form and meanings?meanings?
Successful comprehension of any Successful comprehension of any intended linguistic expression cannot intended linguistic expression cannot be achieved without some be achieved without some commonality of thought.commonality of thought.
Language LearningLanguage Learning
Language learning is possible because Language learning is possible because babies can organize categories in babies can organize categories in much the same ways as their adult much the same ways as their adult caretakers do.caretakers do.
Language LearningLanguage Learning
Child sees only a few exemplars of dog....how does she learn to extend the word to all these different types of dogs?
Dogs
Shmogs
Word LearningWord Learning Children develop reasonable biases in how Children develop reasonable biases in how
to interpret meanings of novel wordsto interpret meanings of novel words– Development of these biases may be influenced Development of these biases may be influenced
by naming practices of the target language by naming practices of the target language being learned being learned
They draw on various sources of They draw on various sources of information in learning word meaningsinformation in learning word meanings
– Social cuesSocial cues– Linguistic cuesLinguistic cues
State of the learner’s linguistic knowledge State of the learner’s linguistic knowledge will dictate sources of information recruitedwill dictate sources of information recruited
Word Learning BiasesWord Learning Biases
Mutual ExclusivityMutual Exclusivity Assume that every object has just Assume that every object has just
one name (E. Markman)one name (E. Markman) Less limited: assume that there Less limited: assume that there
are no synonyms (E. Clark)are no synonyms (E. Clark)
Mutual Exclusivity in Mutual Exclusivity in ActionAction Experimenter “Look here’s a dax”Experimenter “Look here’s a dax”
Mutual Exclusivity in Mutual Exclusivity in ActionAction Child ....that’s a telephone Child ....that’s a telephone
it can’t be a daxit can’t be a dax
Mutual Exclusivity in Mutual Exclusivity in ActionAction Child ....so that other thing must Child ....so that other thing must
be a dax!be a dax!
18 months-olds can do this…
Social PerspectiveSocial Perspective
Word learning occurs in a social contextWord learning occurs in a social context Child is NOT attempting to map a word to Child is NOT attempting to map a word to
something in the worldsomething in the world Child is attempting to discover another Child is attempting to discover another
person’s intention to referperson’s intention to refer– Referent = the thing/event/action in the world that Referent = the thing/event/action in the world that
an instance of the word refers toan instance of the word refers to– Meaning = the concept that is paired with a wordMeaning = the concept that is paired with a word
Word learning is an attempt at mind reading!Word learning is an attempt at mind reading!
Joint ReferenceJoint Reference
Joint Reference: when speaker and Joint Reference: when speaker and listener both interpret a phrase as listener both interpret a phrase as referring to the same thingreferring to the same thing
Achieved through joint attention Achieved through joint attention based onbased on– Prior linguistic contextPrior linguistic context– Shared goals or world knowledgeShared goals or world knowledge– Visual attention to physical contextVisual attention to physical context
Baldwin (1991)Baldwin (1991)Social Cue - Joint Social Cue - Joint ReferenceReference
1
2
1
2
Follow-In:Mom looks at same thing.
Disjoint:Mom looks at different thing.
Mom then says: “Oh, look at the toma! See that toma? Wow, that’s a toma!” Child then asked to identify “toma”.
18 months-olds succeed at tracking where mom is looking and using that to determine what is the “toma.”
Children make use of the linguistic context in which words appear
Verb vs. nouns
Mass nouns (e.g. sand)
Count nouns (e.g., dog)
Linguistic ContextLinguistic Context
$#>@)(!&%
He’s sebbing!
Brown, 1957
Using Linguistic Using Linguistic ContextContext
Look, a seb!
Using Linguistic Using Linguistic ContextContext
Brown, 1957
Using Linguistic Using Linguistic ContextContext
Look, some seb!
Brown, 1957
State of the learner’s State of the learner’s linguistic knowledge and linguistic knowledge and information recruitedinformation recruited• • Initially, child has impoverished information Initially, child has impoverished information
about linguistic context and the structure about linguistic context and the structure of the worldof the world– Don’t understand many wordsDon’t understand many words– Don’t understand much about syntaxDon’t understand much about syntax
Shared physical context must be keyShared physical context must be key Speakers attention can be inferred through:Speakers attention can be inferred through:
– eye gazeeye gaze– body orientationbody orientation– gesturesgestures
Vocabulary growthVocabulary growth
By the age of 3 years, children have been By the age of 3 years, children have been learning about 8 new words a daylearning about 8 new words a day
AgeAge Language DevelopmentLanguage Development
1-2 months1-2 months Cooing (oh, ah)Cooing (oh, ah)
6 months6 months Babbling (ba)Babbling (ba)
8 months8 months Reduplicated Babbling (bababababa)Reduplicated Babbling (bababababa)
10 months10 months Variegated Babbling (badago)Variegated Babbling (badago)
1 year1 year First words (mummy)First words (mummy)
Repeating sound sequencesRepeating sound sequences
1-1.5 years1-1.5 years One word stage (3-50 words) One word stage (3-50 words)
2 years2 years Two-word or Telegraphic stageTwo-word or Telegraphic stage
2-2.5 years2-2.5 years Word SpurtWord Spurt
3 years3 years Intelligible to strangersIntelligible to strangers
Receptive vocabulary: 1200-2000 Receptive vocabulary: 1200-2000 wordswords
4 years4 years Speak grammaticallySpeak grammatically
6 years6 years Receptive vocabulary: 14,000 wordsReceptive vocabulary: 14,000 words
Some Milestones in Language Development
What caused the rapid What caused the rapid vocabulary vocabulary development?development? Conceptual Development?Conceptual Development? Changes in Representations of Changes in Representations of
the Input?the Input?– What kinds of words are easily What kinds of words are easily
learned through observation?learned through observation?– What kinds of words rely on What kinds of words rely on
knowledge of words and syntax for knowledge of words and syntax for learning?learning?
Vocabulary Vocabulary CompositionComposition
Common Nouns
Predicates
Close Class
Perc
en
t of
Tota
l V
ocab
ula
ry 60
50
40
30
20
10
0
# of Words in Vocabulary
from Bates, E., Dale, P. S., & Thal, D. (1995).
Experiment: Limits of Experiment: Limits of ObservationObservation Question: Which words are easier Question: Which words are easier
to learn from observation? to learn from observation? To answer question: Gleitman & To answer question: Gleitman &
colleagues asked adult speakers colleagues asked adult speakers who are “cognitively mature” to who are “cognitively mature” to view SCENES of what mothers are view SCENES of what mothers are saying to their children and see saying to their children and see which words they could learn.which words they could learn.
Experiment with English SpeakersSnedeker, Gleitman, and Brent (1999)
Stimuli preparation1. Videotape English speaking mothers playing with their 18-24 month old children
2. Transcribe video tape for mothers’ 24 most frequent nouns and 24 most frequent verbs.
3. For each of the most frequent word, randomly select 6 uses of the word.
4. Edit each instance for 40 second clips. Audio was removed and a beep is sounded at instant word uttered.
Final Guess
On to Next Mystery Word
watch clip #6
watch clip #5
watch clip #4
watch clip #3
watch clip #2
watch clip #1
Subject’s Task: Identify the “mystery word” represented by the beep.
Guess word.
Guess word again.
Guess word again.
Guess word again.
Guess word again.
Guess word again.
Percent Correct Identification in English
Snedeker, Gleitman, and Brent (1999)
0%
5%
10%
15%
20%
25%
30%
35%
EnglishPer
cen
tag
e o
f C
orr
ect
Iden
tifi
cati
on
Noun Verb
Why nouns differ from Why nouns differ from verbs in ease of verbs in ease of acquisitionacquisition Nouns typically name objects and Nouns typically name objects and
Verbs typically name eventsVerbs typically name events Objects persist, events typically do notObjects persist, events typically do not Object concepts and event concepts Object concepts and event concepts
are organized differentlyare organized differently– Hierarchies for objectsHierarchies for objects– Dimensions for eventsDimensions for events– Leads to multiple salient categorizations Leads to multiple salient categorizations
for all event WITHIN a language (fewer for for all event WITHIN a language (fewer for object)object)
Dividing words up into Concreteness Categories English Experiment -- Snedeker, Gleitman, and Brent (1999)
* BLOC = Basic Level Object Category
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
24 Nouns vs. 24 Verbs 12 BLOCs vs. 12 Non-BLOCs
(Nouns)
13 Observables vs. 11 Unobservable
(Verbs)
Per
cen
tag
e o
f C
orr
ect
Iden
tifi
cati
on
NounVerb
24 Nouns
24 Verbs
*BLOCNon-BLOC
e.g. dog
e.g. thing
ObservableUnobservable
e.g. throw
e.g. think
Proposal for Proposal for Vocabulary Vocabulary DevelopmentDevelopment1. Scenes:1. Scenes:
– Child relies on situational context Child relies on situational context alonealone
– Can learn only very concrete words: Can learn only very concrete words: object labelsobject labels
Proposal for Proposal for Vocabulary Vocabulary DevelopmentDevelopment2. Nouns:2. Nouns:
– Object labels Object labels richer richer representation of linguistic contextrepresentation of linguistic context
– – Utterance = set of known nounsUtterance = set of known nouns– Child can learn concrete relational Child can learn concrete relational
words spatial prepositions many words spatial prepositions many verbsverbs
Hear 3 nouns (man, apple, you)….man…..GORP…apple….youVs.Hear 2 nouns (man, apple)….man…..GORP…apple
How knowing some How knowing some words will help words will help learning…learning…
Proposal for Proposal for Vocabulary Vocabulary DevelopmentDevelopment3. Syntactic Frames:3. Syntactic Frames: Learning relational words allows Learning relational words allows
the child learn the basic grammar the child learn the basic grammar of her languageof her language
Utterance is represented as a Utterance is represented as a syntactic structure + known wordssyntactic structure + known words
This representation allows the child This representation allows the child to learn more abstract wordsto learn more abstract words
Examples of words Examples of words learnedlearned by 12 months (scenes):by 12 months (scenes):
– mommy, bottle, telephone, cup, himommy, bottle, telephone, cup, hi by 20 months (nouns):by 20 months (nouns):
– go, sit, hug, hand, big, upgo, sit, hug, hand, big, up 30+ months (frames):30+ months (frames):
– by, around, listen, think, other,by, around, listen, think, other,
Snedeker & Gleitman (2002)Snedeker & Gleitman (2002)
Targets Targets – Videotaped interactions of 4 mother-child pairsVideotaped interactions of 4 mother-child pairs– 24 most common 24 most common verbsverbs chosen as targets chosen as targets– for each target 6 instances randomly selectedfor each target 6 instances randomly selected
Ss participated in one of 7 Information Ss participated in one of 7 Information ConditionsConditions– ScenesScenes– NounsNouns– FramesFrames– Scenes + NounsScenes + Nouns– Scenes + FramesScenes + Frames– Nouns + FramesNouns + Frames– Scenes + Nouns + FramesScenes + Nouns + Frames
Scenes ConditionScenes Condition
Final Guess
On to Next Mystery Verb
Etc….
Task: Subjects guess mystery verb from watching 6 instances of word use in video clips. The video clips are silent except beeps replace the moments the mystery word were uttered.
Example: “play”
beep
beep
Guess Word.
Guess Word Again.
Nouns ConditionNouns Condition
On to Next Mystery Verb
Example: “play”
Task: Subjects shown the nouns co-occurring with the mystery verb in 6 sentences, the same sentences as those in the video clips with the beeps.
Guess Word.
Guess Word Again.
Guess Word Again.
Guess Word Again.
Guess Word Again.
Final Guess
1. elephant, piano
2. mommy
3. I, it, you
4. it, you
5. drums
6. music, you
1. Can kax SIRN the bussit?
2. Noggle SIRN?
3. Can po SIRN while lo nirp nu?
4. Lo are gonna SIRN nu?
5. SIRN the neps.
6. Lo SIRN tuggy wilm.
Frames ConditionFrames Condition
On to Next Mystery Verb
Example: “play”
Task: Subjects guess the mystery verb from the 6 sentence frames. The sentence frames are constructed by replacing words in the 6 utterances with nonsense words.
Guess Word.
Guess Word Again.
Guess Word Again.
Guess Word Again.
Guess Word Again.
Final Guess
Correct Identification Correct Identification Varies with Information Varies with Information ConditionCondition
Nouns Scenes
Frames
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
% C
orr
ect
on
Fin
al
Tri
al
p < .05
Correct Identification Correct Identification Varies with Information Varies with Information ConditionCondition
Scenes
Scenes+Nouns
Full Info
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
% C
orr
ect
on
Fin
al
Tri
al
p < .05
p < .05
Correct Identification Correct Identification Varies with Information Varies with Information ConditionCondition
Nouns Scenes
Scenes+
Nouns
Frames
Scenes+
Frames
Nouns+
Frames
Full Info
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
% C
orr
ect
on
Fin
al
Tri
al
p < .05
p < .05
p < .05
Word LearningWord Learning
Children develop reasonable biases in how Children develop reasonable biases in how to interpret meanings of novel wordsto interpret meanings of novel words
– Development of these biases may be influenced Development of these biases may be influenced by naming practices of the target language by naming practices of the target language being learned being learned
They draw on various sources of They draw on various sources of information in learning word meaningsinformation in learning word meanings
– Social cuesSocial cues– Linguistic cuesLinguistic cues
State of the learner’s linguistic knowledge State of the learner’s linguistic knowledge will dictate sources of information recruitedwill dictate sources of information recruited