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2011-08-18

読書の記録(2011年7月)

★★★★☆ オプティミストはなぜ成功するか (講談社文庫)


悲観主義者、楽観主義者を実験を通じて解き明かす。あらかじめ、自分の力で自体を変えられることを学んでいれば、無力感に陥らずにすむ。人生の早い段階でこれを学べば学ぶほど、無力に対して有効な免疫力をつけることができる。ということを立証。本書では動物の無気力学習に始まり、現代病とも言われる鬱の根本的な対処法に迫る。単なる自己啓発本に終わらず、様々なデータに基づいた解説が興味深かった。

★★★☆☆ イチローの哲学―一流選手は何を考え、何をしているのか


オリックス時代、イチロー選手の専属打撃投手であった奥村氏の目線から語られるイチロー像。そして、そこから多くの影響を受けた、彼自身の人生や考え方が書かれていた。良かったが、「イチローの哲学」と題する割には少し中途半端な印象。

★★★☆☆ 思考する機械コンピュータ (サイエンス・マスターズ)


amazonの評価が良くて購入。残念ながら、大学レベルの勉強をした人に取ったらあまり読み応えはないだろう。ただ、コンピュータ科学や情報工学の入門書には丁度良いと感じた。簡単すぎず、深入りもしすぎず、大まかな全体像をつかめるだろう。コンピュータとは何か。どんなことを学ぶのか。そんなことを知りたい人にお勧め。

★☆☆☆☆ アップルとグーグル 日本に迫るネット革命の覇者


アップルとグーグルという2大IT企業の個性に焦点を当てている点は良いが、こじつけがましく、あまりにも無理矢理な結論が目立ち、気分良く読み進めることができなかった。なんとなく、この二つの会社がどんなものか適当に知りたいだけの人、或いは“信者”などと言われるような人たちにはには面白く映るかもしれないが、正直得た物は無かった。

★★☆☆☆ 20歳のときに知っておきたかったこと スタンフォード大学集中講義


評判が良かったから読んでみたものの、正直自分には価値が分からなかった。"Thinking outside the box"なんてことはどの分野でも当然のごとく言われていること。様々な分野から実例を元に、主張をサポートしている点は評価できるが、その話の殆どはある程度最新の話題に目を通している人にすれば真新しさに欠る。また「有名な実験映像」と紹介されたバスケットボールの錯覚の話も、Daniel Simonsのオリジナルの実験を知っているが故に今更感や、「熊?」などと疑問を覚えたりもした。しかし確かにタイトルの示すように、10代の人が読む分には、読みやすくもあり、なかなかの良書ではあるのかもしれないと思った。

★★★★☆ イチロー式 集中力


イチローの発言をベースにしたイチロー式集中力の解説本。15分もあれば一通り目を通せるような本。しかしそれは悪い意味ではなく、しっかりとポイントの整理がなされ、結論も明解にまとめられているという意味。それぞれの結論を表現する図もよかった。

★★★★☆ この一言が人生を変えるイチロー思考―夢をかなえる一番の方法 (知的生きかた文庫)


この本がというよりも、様々なイチローの発言がイチロー像を強く目に浮かばせる。
「もがいても、もがいても、何を考えても、何トライしてもダメなときが人生にはあると思うんですけど、そういうときこそ、自分に重荷を課すということが、必要だと思うんです。自分はできないかもしれないけど、それをあえてやるぞっていうことは、すごく大事なことだって、最近思いますね。」(イチロー

★★★☆☆ 常識として知っておきたい日本の三大宗教―神道・儒教・日本仏教 (KAWADE夢文庫)


三大宗教の歴史的背景やしきたりなど、さらっとおさらいする感じ。タイトルにもあるように「常識として知っておきたい」ことを連ねる教科書的な位置づけ。個人的にはもう少しテーマ性を持った流れでまとめられていたらよかったと感じた。

★★★☆☆ ザ・グーグルウェイ グーグルを成功へ導いた型破りな戦略


googleの手法をビジネス的視点から分析してまとめた本。常識にとらわれないgoogleのやり方に、エンジニア心がワクワクさせられた。

2011-08-08

認知心理学12. Language: 言語

認知心理学もくじ

Today

  • How is language organized?
  • How are sentences produced and -comprehended?

  • language
    • a collection of symbols and rules for combining symbols, which can express an infinite variety of messages (CP 244)
  • grammar
    • A set of rules for producing correct sentences in a language (CP 244)

Properties of language

  • Despite all this variation, there are some characteristics that all languages share- and the course of development of language is amazingly similar despite the variety of outcomes.
  • So, some characteristics that are similar for all languages:

Language is..

  • symbolic
    • arbitrary labels
    • The use of symbols, such as spoken or written words, to represent ideas (CP 244)
    • (except in the case of onimonipea) nothing inherent about this object that would lead me to call it x and not ‘chazwouzes’

  • generative
    • Almost limitless combination of words available to make statements
    • The capability to produce many different messages by combining symbols in different ways (CP 244)
    • you can make an almost unlimited number of statements from a relatively small number of possible sounds.

  • structured
    • Rules for expressing ideas (grammar)
    • The organization imposed on a language by its grammatical rules (CP 244)
    • there are rules by which the phonemes and sentences need to be arranged. We are able to learn these rules very quickly.

Organization of language

  • phoneme
    • unit of sound: th, a, aaa; there are about 100 phonemes across all languages, but only about 40 or so get used in a language- speakers of one language often have trouble with unfamiliar phonemes. Fa ra ra ra ra
    • only about 40 in English
    • The treth ef thes stestement shed be evedent frem thes bref demenstreten.
  • morpheme
    • The smallest unit of meaning in a language (CP 244)
    • English has around 50,000
    • Undesirables- un (not) desire (want) able (has the quality of) and s (plural) (There are 11 phonemes)

Organization of language

  • phrase/ propositions
    • groups of morphemes that convey a meaning: in the den, it’s raining
    • Formed according to rules of grammar.
  • sentence
    • organized sequences of words that express a thought or intention
    • organized by syntax
      • the rules that govern the placement of words and phrases in a sentence
      • in English, we don’t say: Why you did come here today?
      • yet we can parse a nonsense sentence such as: The sten befted down the flotway.
    • semantic
      • rules for organizing meaning (constrained by syntax)
      • The woman kissed her date.
        • Could have multiple meanings (is ambiguous), maybe she really likes middle-eastern fruit.
      • The woman kissed her anxious date.
        • meaning is clear because we know through syntax that an adjective modifies a noun and fruit can’t be anxious.

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/01.jpg

  • Language processing in the brain.
    • This view of the left hemisphere highlights the location of two centers for language processing in the brain:
    • Broca’s area: involved in speech production
    • Wernicke’s area: involved in language comprehension.

Aphasias

D
D

  • Broca’s aphasia
    • For them, speech is difficult to initiate, non-fluent, labored, and halting.
    • A language disorder attributed to damage in the frontal lobe of the brain (CP 247)
    • difficulty producing language
    • Paralysis on right side of body
    • Song repetition intact

D

The nature/nurture of language development

  • Nature provides:
    • 10 months- phoneme sensitivity (forming prototypes)
      • below 10 months of age can discriminate between all known phonemes.
    • ‘Perceptual magnet’
      • sounds get pulled closer to their prototypes.

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/02.jpg
(Werker, 1989)

What is learned

  • How to make phonemes.
  • How to combine phonemes to create words and sentences.

Schematic of language

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/03.jpg

Hierarchical organization of speech

  • Looking at how grammar constrains speech errors indicates hierarchical organization of speech.
  • Speech errors
    • slip of the tongue
      • A speech error (CP 250)
    • exchange error
      • An error in which two linguistic units are substituted for each other during sentence production (CP 250)
      • word exchange:
        • An error in which two words are substituted for each other during sentence production (CP 250)
        • usually occur between members of the same syntactic category. Both adjectives
        • “I’m not as think as you drunk I am.”
      • morpheme exchange:
        • An error in which two morphemes are substituted for each other during sentence production (CP 250)
        • it is the stems or suffixes that are exchanged. In this case, the stems slice and thin are interchanged with the suffixes ly and ed which remain in their original position
      • phoneme exchange:
        • initial consonants can be exchanged with other initial consonants
        • An error in which two phonemes are substituted for each other during sentence production (CP 250)
        • “lork yibrary”

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/04.jpg

NOAM CHOMSKY’S (1957) THEORY OF LANGUAGE

  • PHRASE STRUCTURE GRAMMAR
    • Divide these sentences into meaningful parts:



The strongyouthscarriedthe heavy boxes
  Noun phrase  Verb phrase
AdjectiveNounVerbNoun phrase
The doctorconsoled the grieving parent.
Noun phraseVerb phrase
The cottageacross the lakewas purchased
 Noun phraseVerb phrase
Noun phraseAdjective phraseverb phrase

Phrase Structure Grammar alone is insufficient.

  • “The dog is chasing the cat.”
    • phrase structure simply tells us how we can partition this sentence into smaller grammatical units.
  • Which sentence is most like the KERNEL sentence(核文)?
    • “The cat is chasing the dog.”
      • Similar in PHRASE STRUCTURE
    • “The cat is being chased by the dog.”
      • Similar in MEANING

Another issue with phrase structure grammar

  • Flying planes can be dangerous
    • Surface structure mapped onto two meanings
    • flying planes are dangerous to the pilot.
    • the planes themselves are dangerous.
  • The problem is that the sentence can only be partitioned in one way; thus, the ambiguity cannot be resolved using different phrase structure rules.

NOAM CHOMSKY’S (1957) THEORY OF LANGUAGE

  • transformational grammar:
    • an alternative to the phrase structure grammar because it describes both the grammatical structure an how sentences can be transformed.
    • A set of rules for transforming a sentence into a closely related sentence (CP 252)
    • “The dog is chasing the cat.”
  • Transform the KERNEL into PASSIVE TENSE:
    • “The cat is being chased by the dog.”
  • Transform the KERNEL into a NEGATION:
    • “The dog is not chasing the cat.”
  • Transform the KERNEL into a QUESTION:
    • “Is the dog chasing the cat?”
  • Transform the KERNEL into a ALL THREE:
    • “Isn’t the cat being chased by the dog?”
  • Transformational grammar alone is insufficient.
    • Puffy clouds relax the couch.”
  • Transform the Kernel into PASSIVE TENSE:
    • “The couch is relaxed by puffy clouds.”
  • Transform the Kernel into a NEGATION:
    • Puffy clouds do not relax the couch.”
  • Transform the Kernel into a QUESTION:
    • “Do puffy clouds relax the couch?”
  • ''PROBLEM'': Although transformational grammar provides the rules for transforming sentences into various meanings, it does not guarantee that a sentence will be meaningful.
    • Chomsky tried to rectify this problem by placing constraints on which words could be used and substituted in a sentence.
    • In this example, the verb relax requires an animate object.
      • Clouds and couch’s don’t relax.

NOAM CHOMSKY’S (1957) THEORY OF LANGUAGE

  • To help understand these problems with transformational grammar, Chomsky included two levels.

1. surface structure:

2. deep structure:

    • the meaning of a sentence
    • The underlying meaning of a sentence (CP 254)
    • Allows the extraction of the kernel from various transformations

EVIDENCE FOR TRANSFORMATIONAL GRAMMAR: ''Chase & Clark (1972)''

  • Processing negative transformations
    • STAR IS TO RIGHT OF PLUS. +- (KERNEL SENTENCE)
  • Negative transformation:
    • STAR IS NOT LEFT OF PLUS. +- (TRANSFORMATION)
  • To evaluate this sentence, we first mentally transform it to its kernel sentence:
    • ''STAR IS TO RIGHT OF PLUS. +- (KERNEL SENTENCE)''
  • This transformation takes time to process.

Semantic influence on syntactic parsing

  • Animate vs. inanimate nouns
    • The defendant examined by the lawyer turned out to be unreliable.
      • Eye-tracking data show that people slow down when they reach “by the lawyer” in the first sentence.
      • The reason is that Ss expect the verb examined to be the main verb which should then be followed by a noun phrase.
    • The evidence examined by the lawyer turned out to be unreliable.
      • Ss do not experience this slow down because there assumption that examined is the main verb is correct.
  • In other words, the context (whether the sentence begins with and animate or inanimate noun) influences the ease of later comprehension.

Semantic Context and Word Recognition

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/05.jpg

  • When we read something semantic context can facilitate recognition of later words
    • Ex: we’ve all encountered handwriting that is difficult read, an we can often use previous words to identify an illegible word.
    • We don’t have any trouble reading and comprehending either of these two sentences even though the two sentences contain a physically identical word.
    • The context in both sentences allows us to correctly guess which word comes next and thus we interpret it correctly.

  • high-constraint sentence:
    • Produce an expectation for a given word.
    • A sentence that produces a high expectation for a particular word (CP 257)
    • John kept his gym clothes in a locker
    • John kept his gym clothes in a closet
  • In H.C. sentences reaction times are slower when the word is not expected.
  • low-constraint sentence:
    • Produce an expectation for a broader range of words.
    • A sentence that produces an expectation for a broader range of words (258)
    • The lady was a competent chef
    • The lady was a competent cook
  • In L.C. sentences both the expected and unexpected word have equally fast reaction times.

Contextual factors

  • Although he was continually bothered by the cold…
  • When we read this partial sentence, the word cold is somewhat ambiguous without any prior context.
  • Thus, it is unclear whether cold refers to the temperature or whether it refers to the subjects health.

Processing ambiguous words: ''Swinney & Hakes, 1976''

  • Swinney tested whether a clarifying context made an ambiguous sentence easier to comprehend.
  • ambiguous sentence
    • A sentence that has more than one meaning (CP 252)
  • 2 tasks simultaneously while listening to pairs of sentences.
    • Task 1- rate how related 2 sentences are
      • requires comprehension
    • Task 2- push a button when a particular phoneme is heard.
      • slower response when they are having trouble comprehending the sentence
  • IV: type of text (ambiguous or contextualized)
  • DV: RTs for button press

  • Target phoneme: /k/ (in corner)
  • (1) Rumor had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several ''bugs/ insects'' in the __c__orner of his room. (ambiguous)

  • Findings: RT for bugs > RT for insects
    • In the control condition bugs was replaced with insect and responses were significantly faster when word insect.

  • (2) Rumor had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other ''bugs'' in the __c__orner of his room. (contextualized)
    • In this version the preceding context sets up the word bugs for the correct interpretation.
    • 1 interpretation: correct context activates only a single meaning of the word
  • Findings: RT for +1 > RT for +2

What happens to alternative interpretations of words?

  • BUG- insect related meaning/ spy-related meaning
  • Swinney, 1979
    • Swinney did another experiment to test whether ambiguous words activated multiple meanings of the word or only one meaning.
    • Same study except phoneme detection task became lexical decisions.

  • lexical decision task
    • A task that requires people to decide whether a string of letters is a word (CP 257)

  • Ss heard this sentence:
  • Rumor had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several bugs -in the corner-- of his room.
    • The asterisks represent when the lexical decision task occurred. Immediately after bugs or after a delay of four syllables.
  • Test words:
    • Appropriate interpretation: ANT
    • Inappropriate interpretation: SPY
    • Unrelated: SEW
  • However, it is those four syllables that disambiguate the word bugs.

  • Results
    • IV: timing of lexical decision task
    • DV: RT for lexical decision
    • At -: ANT = SPY < SEW
    • At --: ANT < SPY = SEW
  • What we see is that when the task occurs immediately after the word, bugs both ant and spy are faster than the non-related word.
  • But there is no difference in reaction times between ant and spy.
  • However, when the task occurred after the delay responding to ant was significantly faster than responding to either spy or sew.
  • →both meanings of an ambiguous word are activated momentarily, and the context allows the Ss to select the correct meaning quickly.
  • Activating both meanings in ambiguous words is an advantage.
    • If only one, the most frequent, meaning was activated, it would takes a great deal of time longer to have go back and activate and select the alternative meaning when we ran into a sentence requiring the alternative.

Individual differences

  • Factors influencing ambiguity resolution
    • Reading skill
      • Poor readers are unable to suppress the inappropriate meanings of ambiguous words.
    • working memory capacity
      • The amount of information that can be kept active in working memory (CP 261)
  • Since Ken really liked the boxer, he took a bus to the nearest…
    • Boxer: the dominant meaning is that of a fighter, while the less dominate meaning is that of a dog.
  • Readers with small capacities had trouble resolving the ambiguous word if it turned out to refer to a dog (the less dominate meaning).
    • Good readers have larger working memory capacities, thus keeping both meanings active in working memory is easy.
    • However, poor readers have smaller capacities and are therefore only able to maintain the dominant meaning for any length of time.

error recovery heuristic

  • A strategy for correcting comprehension errors (CP 261)
  • Used for correcting comprehension errors
    1. Reinterpret the inconsistent word
    2. Check previous words that might have lead to the difficulty
    3. Read on for further information
    4. Elaborate on the inconsistency to make it consistent

Read out loud the sentence that will appear below

''CINDERELLA WAS SAD BECAUSE SHE COULDN’T GO TO THE DANCE THAT NIGHT. THERE WERE BIG TEARS IN HER BROWN DRESS. ''(CARPENTER & DANEMAN, 1981: Error recovery heuristics)

  • Read out loud the sentence that will appear on the next slide

''THE YOUNG MAN TURNED HIS BACK ON THE ROCK CONCERT STAGE AND LOOKED ACROSS THE RESORT LAKE. TOMORROW WAS THE ANNUAL FISHING CONTEST AND FISHERMEN WOULD INVADE THE PLACE. SOME OF THE BEST BASS GUITARISTS IN THE COUNTRY WOULD COME TO THE SPOT. THE USUAL ROUTINE OF THE FISHING RESORT WOULD BE DISRUPTED BY THE FESTIVITIES.'' (CARPENTER & DANEMAN, 1981)


Beyond the words: inferences

  • The angry swarm of bees flew out of the hive and landed on Joan's hand. Her hand was soon very sore and she regretted having bothered the insects.
  • In this case we are able to use language to imply something without explicitly asserting it.

''Bransford, Barclay & Franks, 1972''

http://dl.dropbox.com/u/3770752/wiki/cognitive/13/06.jpg

  • Studied the effects of inferences on memory.
  • Three turtles rested on a floating log, and a fish swam beneath them.
  • Specifically they studied how subjects would falsely recognize implied statements.

  • Recognition sentence:
    • Three turtles rested on a floating log, and a fish swam beneath them.
  • Comparison condition:
    • Three turtles rested beside a floating log, and a fish swam beneath it.

  • Recognition sentence:
    • Three turtles rested beside a floating log, and a fish swam beneath them.
  • Comparison condition:
    • Three turtles rested beside a floating log, and a fish swam beneath it.
  • Here they do not make a false recognition because the comparison sentence is not implied by the recognition

認知心理学もくじ

2011-08-02

認知心理学11. Semantic Organization: 意味的組織化

認知心理学もくじ

Today

  • How do we store meaning?

What is semantic memory?

  • Memory of meaning
  • Based on relationships between concepts
  • Organized hierarchically
  • Will organized presentation lead to better recall?
  • hierarchical organization:
    • Influences the amount of information retrieved
    • And the time required to retrieve information.

Recall: random vs. hierarchical: ''Bower, Clark, Winzenz, & Lesgold, (1969)''

  • Ss presented with different nested category lists.
    • 28 words in each
    • Studied each hierarchy for 1 min
  • IV: Hierarchical organization or random presentation
  • DV: number of words recalled in a free recall task.

In the hierarchical organization condition the items were presented with the conceptual hierarchies you just saw.
In the random condition Ss saw the same words but they were inserted randomly within each spatial tree.
For example, if the conceptual hierarchies include instruments, plants, minerals, and body parts.
Each spatial tree would include items from each category randomly placed.


http://dl.dropbox.com/u/3770752/wiki/cognitive/12/hierarchical%20organization.jpg

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/random%20org.jpg

Recall: random vs. hierarchical: ''Bower, Clark, Winzenz, & Lesgold, (1969)''

  • Results:

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/result.jpg

  • A hierarchy can be used as a effective retrieval plan for cuing recall.

Sentence Verification Task

  • The amount of time it takes a person to respond provides clues about the organization of semantic memory
  • sentence verification task

Semantic Network Model: ''Collins & Quillian, (1969)''

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/semantic%20network%20model.jpg

  • semantic network
    • model of organization where related concepts are arranged in a network
  • This represents the way concepts are organized in the mind
    • Nodes
    • Links
  • Features true of all animals stored at the top level.
    • Animals eat
  • Features true of specific, basic-level categories are stored in the middle level.
    • Birds have wings
  • Features specific to a certain species are stored at the bottom level.
    • Canaries are yellow
  • A semantic network suggests that semantic information is organized based on relationships.

Effectiveness of Semantic Networks: ''Holley & Dansereau (1984)''

  • Ss study a 3000-word passage.
  • 1/2 Ss received training on constructing semantic networks.
  • Test:
    • Multiple choice
    • Short answer & essay
  • Using semantic networks is a good method for organizing knowledge.

Sentence Verification

  • As those first studies demonstrated both hierarchical and semantic organization increase, the amount of information subjects are able to recall, and several theories have been proposed to account for this.
  • Two theories:
    1. hierarchical network model: uses hierarchical relations for semantic info.
    2. semantic feature-comparison model: match test items to features in the category.

Hierarchical Network Model: ''Collins and Quillian (1969)''

  • But if semantic information is hierarchically organized, it should also influences the time it takes to retrieve information.
  • Two primary assumptions:
    1. Moving from one level of the hierarchy to another takes time.
    2. Having to retrieve features contained at each level takes additional time

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/semantic%20network%20model.jpg

  • First assumption is that it takes more time to move between levels.
    • For example responding to the question "is a salmon animal?" should take longer then answering "whether a salmon is a fish".
  • The second assumption states that it will take even more time if we have to retrieve the features contained within each level
    • Subjects should respond faster to salmon is a animal than to a salmon breathes.

  • Ss respond T or F to property and category questions.

Category QuestionsProperty Questions
A canary is a animal.A canary eats.
A canary is a bird.A canary can fly.
A canary is a canary.A canary is yellow.
  • category question
    • ask about a set of relations. Is one category a member of another
  • property question
    • ask about features contained within each category level.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/Collin.jpg

  • Hear:
    • A canary can fly. or A canary can sing.
  • Verify:
    • A canary is a bird.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/Canary.jpg

Problems

  • Instances in which RT’s are not influenced by the levels of the hierarchy.
    • A Chimpanzee is a primate.
    • A Chimpanzee is a animal.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/chimp.jpg

  • the model predicts that Ss should respond faster to primate than to animal.
  • However, responding is slower for primate rather than animal.

  • Hierarchical model doesn’t account for the typicality effect.
    • Canary is a bird.
    • Ostrich is a bird.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/Canary.jpg

  • According to the typicality effect, typical members of a category should be easier to classify then less typical members.
  • Thus, we should and do respond faster to canary is a bird rather then a ostrich is a bird.
  • However, the hierarchical model predicts that there will be no difference in response times between the to because they are same distance away from the next level.

Feature-Comparison Model: ''Smith, Shoben, & Rips (1974)''

  • The feature-comparison model attempted to overcome the limitations of the hierarchical model by proposing an alternative approach
  • Assumptions
    1. Semantic meaning can be represented in memory as feature lists
    2. Classifications are made by comparing features rather than examining links in a network

Feature-Comparison Model: ''Smith, Shoben, & Rips (1974)''


CanaryBird
Physical objectPhysical object
LivingLiving
AnimateAnimate
FeatheredFeathered
Flies
Yellow
Sings

Feature-Comparison Model

  • defining feature:
    • Features the object must have to be a member of the category
    • Distinguishes between two types of features
    • その物体の種に共通すること

  • characteristic feature:
    • Features usually present but not necessary for category membership
    • 鳥の中でカナリアを区別するための特徴


Canarytypes of feature
Physical objectD
LivingD
AnimateD
FeatheredD
FliesC
YellowC
SingsC
  • Two stages:
    1. Compare all the features between the two concepts to determine similarity.
      1. If initial comparison reveals high or low similarity, then a decision can be made immediately
    2. If similarity lies between the two extremes examine just the defining features
      1. Needed when the similarity between the category concept and the example decreases

  • To determine if a canary is a bird, we would compare all the features of a canary with all the features of a bird.
    • For example we often make very quick decisions about classification because the two items are highly similar.
  • When two items are very highly similar, we have no need to focus on the defining characteristics within the second stage.
  • In other words, we should be quicker to classify typical examples robin, sparrow and blue jay as birds.
  • Then, examples that are less typical of the category like chicken, goose, and duck.

  • What about negative examples?
    • A bat is a bird.
    • A bat is a bottle of wine.

  • We see that when we have a highly typical positive example, a canary is a bird, we can make an immediate judgment without having to rely on the defining features of the category.
  • Feature-Comparison Model predicts the opposite for negative examples that share similar features
  • Bats are not birds, but they have certain features that are highly similar to birds.
  • And because they share many feature, it is difficult to make a quick rejection during the initial feature comparison.
  • Therefore the probability increases that you will engage in the second processing stage and examine the similarity between the concepts defining characteristics.
  • So the feature-comparison model accounts for why some false statements are evaluated quicker then others which the hierarchical model failed to do.
  • A negative response also.
  • however, because the items are highly dissimilar, we can make an immediate judgment about classification which we could in the first example.

  • category-size effect:
    • members of smaller categories can be classified quicker then members of larger categories
  • So determining that a canary is bird, will be faster than determine that a canary is an animal.
  • However, this also true for the hierarchical model.
  • Classifying a canary as a bird takes fewer inferences then having to classify it as a animal.
  • In other words, the example should be more similar to smaller category then to the larger category.
  • However, there cases when the category size effect is violated.
  • The feature model is able to account for these violations because its predictions are based on similarity rather than category size.

Limitations

  • Relies on similarity ratings based on features to make predictions.
    • Weak predictions
  • Classifications require computation
    • Uses features to detect the degree of similarity
  • Little support for the use of defining features

  • we have very little evidence that feature comparison is really what people do.
    • Therefore, the predictions made with this model are weak.
    • On the other hand, the hierarchical network model doesn’t even make these predictions.
  • Computation was emphasized in the last chapter on the categorization of novel pattern. And it was essential for that.
    • But once we have classified a concept, is it really necessary to continue to compute the degree of similarity?
    • It would seem to be much easier to use associations among concepts.
    • For example, once we have learned that a robin is a bird, is it really necessary to compute the degree of similarity between the two every time.
    • It would be easier just to directly use the information you had learned.
  • The model proposes that we use defining features only in the second stage and not the first.
    • However, we can argue that all features are more or less defining.
    • Even characteristic features can be used to define, and only the more defining features are used in the 2nd stage.
    • But again, there is almost no empirical evidence that subjects actually do this.
    • And there is some evidence that the opposite is true.

Limitations: ''Keil & Batterman (1984)''

  • This smelly mean old man with a gun in his pocket came to your house one day and took your color television set because you parents didn’t want it anymore and told him he could have it. Could he be a robber?
  • This very friendly and cheerful woman came up to you and gave you a hug, but then she disconnected your toilet bowl and took it away without permission and never returned it. Could she be a robber?

Limitations

Spreading activation models: ''Collins and Loftus (1975)''

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/01.jpg

  • The spreading activation model is similar to the semantic network models, because of its emphasis on concepts joined together by links.
  • However, in the spreading activation model, the length of each link represents the degree of semantic relatedness between two concepts.
    • For example sunsets are more closely related to sunrises and clouds than to the color red.
  • This model also accounts for the typicality effect.
    • Shorter links suggest that the object is a more typical example of the category, while longer links indicate that the object is not a typical member of the category.

  • Assumptions:
    • Activation decays with time
      • Street to cloud. Takes longer.
    • Activation decays with distance
      • red to house
    • Activation from a node is proportional to the number of pathways (fan effect)

  • fan effect
    • 概念に伴う連合の数が多いと,再認課題においてプローブへの反応時間が増大する現象である。


Testing spreading activation: ''Meyer & Schvaneveldt (1975)''

  • lexical decision task
Word or Nonword?
BALF
BUTTER
BREAD-> BUTTER
RIVER -/->BUTTER
  • The important part is that people respond faster to butter when they had first seen bread rather than river.
  • Spreading activation accounts for this because activation of a word should activate related words.
    • Butter should be activated by bread but not by river.
  • Thus, activation of one word makes it easier to identify related words result in faster response times for related words but not unrelated words.

Testing spreading activation: ''Ratcliff & Mckoon (1988)''

  • spreading activation predicts that activation of information continue beyond a single node.
  • Lion and tiger are associated.
  • And tiger is associated with stripe but lions aren’t associated with stripes.
  • According to the model activation should spread form lion to stripes , but stripe should be less activated then tiger because activation decreases with distance.
-LION ---->(TIGER) -> STRIPE
-LADDER -> (???)--> STRIPE
  • And this is exactly what we find.
  • Subjects are faster to respond to stripe when lion is presented first than when ladder is presented first.
  • Furthermore, subjects respond faster to tiger after being primed lion then responding to stripe after being primed with lion
  • Activation can spread to more distant nodes

Limitations

  • Too flexible.
  • Hard to test the model
  • Predictions of what will not happen are difficult to generate
  • Advantage to semantic networks is that they are flexible.
    • We can introduce new assumptions when the current ones fail to account for empirical findings.
  • One seemingly advantage to the spreading activation model is feature matching allows for the verification of semantic relations.
  • However, the downside is that it is hard to test this.
    • Flexibility is useful to point. If a model becomes so flexible that we can use it to account for all the data; then, it losses its predictive power.
    • And a models predictive power comes from it being able to also predict what will not happen.
  • Thus, it is hard to test this model because the assumptions inherent to it make it difficult to predict when something will not happen.
  • However, people still like this model.
    • It is fairly simple to understand the assumptions are clear.
    • We can also use variants of it study other issues cognitive psychologists are interested such as how we integrate information

So Far…..

  • amodal
    • the knowledge used in these systems are abstracted from our sensory experiences.
    • Knowledge that is abstracted from sensory experiences (CP 233)
  • modal
    • knowledge is represented as sensory experiences (CP 233)
  • They are not representative of the perceptual experiences we actually encounter

Amodal model

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/02.jpg

  • Neurons in feature maps produce sensory representation.
  • Perceptual states are abstracted into non-representational format.
  • Feature lists and semantic networks.

Perceptual Symbol Systems

  • assumes that verification of semantic statements occurs through mental simulations.
  • are directly stored in LTM.
  • modal approach because it stores sensory experiences such as audition, vision, taste, smell, and touch.
  • receive information from LM by reenacting or simulating perceptual experiences.

「鷹が飛んでいる」という文を見せたあとに、翼を開いている鷹の絵と翼を閉じている鷹の絵の双方に対してマッチングタスクを行ったところ、 前者の方がその意味する状況に即しているので反応時間は速くなるという例(Zwaan et al. , 2002)。

  • Form of grounded or embodied cognition.
    • Memories are mental simulations of past events- of how we have perceived things and interacted with them.
  • Can also be used to explain sentence verification tasks

Modal systems

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/03.jpg

  • Simulation is the reenactment of perceptual, motor, and introspective states acquired during experience with the world, body, and mind.
  • As an experience occurs (e.g., easing into a chair), the brain captures states across the modalities and integrates them with a multimodal representation stored in memory (e.g., how a chair looks and feels, the action of sitting, introspections of comfort and relaxation

Zwaan, Stanfield & Yaxley (2002)

  • The ranger saw an eagle in the sky.
  • The ranger saw an eagle in the tree.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/04.jpg

Zwaan & Yaxley (2003)

  • Presented Ss with words pairs placed above or below each other.
AtticLakeSwanCandleTaxiNose
BasementBoatSinkFlamePeachMouth
  • Results: subjects faster when word alignment matched alignment of our images.

  • Their first study showed that we are faster to respond when the picture matches the sentence.
  • This suggests that we have different representations for what objects should look like from different perspectives.
  • They argues that is people do use images to help them make the decision; then, using the position of words should work as well.

Pecher, Zelenberg, & Barsalou

  • Simulating:
    • is the reenactment of perceptual, motor, and introspective states acquired during experience with the world, body, and mind.
  • As an experience occurs, the brain captures states across the modalities and integrates them with a multimodal representation stored in memory

  • This suggests that subjects are simulating the perceptual information.
  • If they weren't, subjects should not respond slower to shifts in modality.
  • Semantic networks don’t predict this.
  • Regardless of modality, it’s depend on the how far activation needs to spread to activate that node.

Glenberg & Kaschak (2002):

  • Q: Does the sentence make sense?
    • もし意味が通るようならジョイスティックを上へ、そうでないなら下へ
  • You closed the drawer.
  • You opened the drawer.

Wu (1995)

  • Ss list features of nouns (watermelon) or noun phrases (half a watermelon).
  • Perceptual symbols (half a watermelon would reveal hidden features, red and seeds) predicts more features will be listed for the noun phrase
  • Amodal systems predict no difference because half a watermelon doesn’t contain anymore features than a whole watermelon.
  • Results
    • Ss listed many more characteristics of noun phrases over nouns alone.

Limitations of Perceptual Symbol Systems

  • Not clear as to how information is integrated.
  • Needs to combine perceptual information with the organization of semantic networks.

Clusters of Knowledge

  • semantic network
    • show association but not how an object is used.
    • A theory proposing that semantic information is organized in long-term memory by linking concepts to related concepts (CP 212)
  • perceptual symbol system
    • describe how objects are used but does not represent associations.
  • Although semantic networks are good at organizing large bodies of knowledge, they do not represent clusters of knowledge so well

The ACT Model: ''Anderson (1976)''

  • Assumptions:
    • Knowledge is stored in a semantic network.
    • Network consists of interconnected nodes.
    • Activation spreads from active nodes to activate new nodes and pathways
  • Predicts that the more alternative paths activation can take the slower retrieval will be.
  • Designed to be applicable to variety of cognitive tasks (scanning, inferences, retrieval etc..)
  • Act assumptions a pretty much the same as assumptions in the semantic network.

ACT Model and Retrieval: ''Anderson (1976)''

  • Ss studied sentences
    1. A hippie is in the park.
    2. A hippie is in the church.
    3. A hippie is in the bank.
    4. A captain is in the park.
    5. A captain is in the church.
    6. A debutante is in the bank.
    7. A fireman is in the park.

Anderson 1976

  • IV- is the number of times a particular individual or location is mentioned.
    • Hippie = 3, Captain = 2, park = 3, bank = 2
  • DV- is their reaction to test sentences
    • True: A hippie is in the park
    • False: A hippie is in the cave

  • Did they see the sentence previously or not.
  • RT increase as a function of the number of links to each person node or location node in the network
  • So when they see the sentence, a hippie is in the park, it activates both hippie and park.
  • Ss then must find the path within the network that joins both hippie and park together.

Problems

  • The examples used by Anderson are not easy to integrate
    • There is no context, and thus no story
    • Relations are arbitrary
    • Furthermore, ACT suggests that the more knowledge you have, the slower retrieval will be.
  • Maybe this is why retrieval is so slow and depends on the number links joining the concepts.

Schema Theory

  • schema
    • framework for organizing clusters of knowledge.
    • A general knowledge structure that provides a framework for organizing clusters of knowledge (CP 228)
  • Used to comprehend and store experiences.

  • semantic networks are very good at demonstrating the way in which we organize knowledge together.
  • However, the limitations of semantic networks is that they do not account for clusters knowledge.
  • Schema theory is not a new idea.

Bartlett’s schema theory : ''Remembering (1932)''

  • During this period the S-R approach to psychology dominated and not many people paid any attention to his theory
  • With the reemergence of cognitive psychology in the late 50 and early 60’s, there was renewed interest in Bartlett’s theory.
  • Even though it was born out of the behavioral period of psychology, there are fundamental differences between the S-R approach and Bartlett’s schema theory.

S-R approachSchema Theory
AtomisitcMolar
AssociationisticNonassociationistic
ParticularisticGeneric
PassiveActive
  • Atomisitc vs. molar:
    • S-R approach is atomisitc and based on small units of knowledge (a single stimulus)
    • Schema theory is based on larger units of knowledge combined to form clusters.
  • Assocationistic vs. non-associationistc.
    • S-R approach requires learning an association between the stimulus and response.
    • A schema on the other hand provides a structure for interpreting and encoding aspects of a particular experience.
  • Particularistic vs. generic.
    • S-R approach looks a specific stimulus an the specific behavior it elcits.
    • A schema is more general and may contain an represent s a variety of particular instances.
  • Passive vs active:
    • Learning an association between a stimulus and response such as in classical conditioning is very passive. It just happens
    • However, retrieving a schema from memory is a more active process because one must match a specific experience with the schema that best fits that experience

  • Unfortunately, by 1970 Bartlett’s own students thought his theory was a complete failure.
  • But in 1975, some American cognitive psychologists began arguing that schemas are in fact needed and not just in psychology.
  • They were used to organize knowledge in artificial intelligence, linguistics, and motor performance.

Modern Schema Theory: ''Rumelhart (1980)''

  • How knowledge is represented and how that representation facilitates the use of knowledge
  • they took Bartlett’s theory an refined it.
  • They kept most of the major assumptions, but were more specific as to what these knowledge structures looked like.
  • And one way a schema facilitates the use of knowledge is through scripts.
  • script
    • knowledge about how routine activities are accomplished.
    • Knowledge about what occurs during routine activities (CP 230)


  • There are two possible ways in which a script is organized.

1. centrality of components

    • you think of the more important components before less important components.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/05.jpg

    • For example, lets say you had to change to tire. Using centrality of components, we would expect our script to look like this.
    • This should seem very similar to the semantic network. However in this case, the distance of the links refers to how central that activity is to accomplishing your goal rather than a strong association between an object and its category.

2. sequential order

    • using the temporal or sequential order information in scripts are based on what comes first.

http://dl.dropbox.com/u/3770752/wiki/cognitive/12/06.jpg

  • Centrality vs. Sequential
    • If people use centrality, then they should be fastest verifying important activities.
    • If people use sequential order, they should be fastest verifying earlier activities.
  • So we can generate predictions to test whether we use the centrality of components or sequential order when organizing scripts.

''Galambos & Rips (1982)''

  • Ss rank order activities according to temporal or centrality
  • Another group of Ss were given the name of the script (flat tire) and an activity (take out jack).
  • Task: Time to decide whether the activity was part of the script.

  • They found that Ss responded significantly faster to activities that were central to task, but there was no difference in speed of responses for earlier vs. later events.
  • Supports the centrality of components organization of scripts.

Barsalou & Sewell (1985)

  • Ss had 20 sec to name activities in a script.
    • Central condition: generate actions from the most central to the least central.
    • Sequential condition: generate actions from first to last.

  • Results:
    • Central condition: 6.10 actions
    • Sequential condition: 8.17

  • Barsalou and Sewell didn’t agree with these findings.
    • They believed the results were due to the nature of the task.
    • And that the results would be different with a different experimental procedure.
    • So subjects were able to generate more actions in 20 sec when recalling them in temporal order rather then based on centrality.
  • What this suggests is that both centrality and temporal order influence our memory.
    • Central events provide quick access to the script
    • And temporal order is useful for retrieving the actions contained within a script.

認知心理学もくじ

2011-08-01

認知心理学10. Categorization: カテゴリー化

認知心理学もくじ

Cognition So Far…..

Today

  • How does categorization occur and how does it benefit us.

Categorizing

  • Benefits
    1. reduces complexity of the environment
    2. It is one way in which we identify objects
    3. Reduces the need for constant learning
      1. e.g, categolize classroom so we don't have to learn how to use the classroom
    4. Allow us to perform an appropriate action
    5. Enables us to order and relate classes of objects/events.

Categories

  • “pointers to knowledge”
    • Once you know something is in a category, you know a lot of general things about it.
    • You can focus your energy on specifying what’s special about the object.
    • Help us make inferences about objects.

What are categories?

  • Definitional perspective
  • e.g.: Chair -“a piece of furniture consisting of a seat, legs, back, and often arms, designed to accommodate one person”

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/chair.jpg

How are Classifications Made?

  • concept identification:
    • deciding if an object is an example of a concept based on logical rules.
    • A task that requires deciding whether an item is an example of a concept, where concepts are typically defined by logical rules (CP 187)

  • logical rule:
    • based on logical relations
    • A rule based on logical relations, such as conjunctive, disjunctive, conditional, and biconditional rules. (CP 187)
    • conjunctive rule (small and yellow)
      1. A rule that uses the logical relation "and" to relate stimuls attributes, such as small and square. (CP 187)
    • disjunctive rule (small or yellow)
      1. A rule that uses the logical relation "or" to relate stimulus attributes, such as small or square. (CP 187)

  • rule learning:
    • Ss told the relevant attributes and must discover the rule (small, square)
    • A concept identification task in which people are told the relevant attributes (such as small, square) but have to discover the logical rule.(CP 188)

Concept Identification Paradigm

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/rule%20learning%20and%20conjunctive%20rule.jpg
small and yellowといったら、左上のだけになる
http://dl.dropbox.com/u/3770752/wiki/cognitive/11/rule%20learning%20and%20disjunctive%20rule.jpg
samll or yellowといったら、左の2つ、右下も当てはまる

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/attribute%20learning.jpg

Problems with Concept Identification

  • Artificial
  • Real categories don't need to share attributes
  • Real categories have continuous dimensions
  • Real categories are hierarchically organized.

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/problem.jpg

hierarchical organization: ''Rosch (1976)''

  • an organizing strategy in which larger categories are partitioned into smaller categories (CP 188)
    1. superordinate category
      1. The largest and most general categories
      2. A large category at the top of a hierarchy, such as furniture, tools ,and vehicles (CP 190)
        1. Musical instruments
    2. basic-level category
      1. An intermediate category
      2. An intermediate category in the middle of a hierarchy, such as table, saw, and truck (CP 190)
        1. Horns, Drums, Guitars
    3. subordinate category
      1. Specific categories
      2. A small category at the bottom of a hierarchy, such as lamp table, jigsaw, and pickup truck (CP 190)
      3. Trumpet, Flute, Tuba

  • Hierarchical Organization
CategorySuper-ordinateBasic LevelSubordinate
Musical Instruments168.5
Fruit712.314.7
Tools38.39.7
Clothing31012
Furniture3910.3
Vehicles48.711.2

カテゴリーが上に行けば行くほどshared attributeも減る。

basic-level categoryをclassifyするのが一番早い。

  • Why is categorizing at the basic-level fastest?
  • prototype:
    • represent an average pattern for an object
    • An item that typifies the members in a category and is used to represent the category (CP 193)

  • But is this true for experts?
  • Dog experts vs. Bird experts

犬の専門家は、鳥のbasicを分類するのはとても早かったが、鳥の専門家はsub ordinateと同じくらい時間がかかった。

Problems with Concept Identification

  • Artificial
  • Real categories don’t need to share attributes.
  • Real categories have continuous dimension.
    • An attribute that can take on any value along a dimension (CP 188)
  • Real categories are hierarchically organized.
  • ''Its fundamental.'' ←new

The fundamental-ness of categories: ''Kenneth and Cuff (1989)''

  • Ss 36, 9-15 month old infants
  • Habituated infants to 3 kinds of animals
    • Cat, Cow, Horse
  • Later present 6 new animals.

  • Results:
    • Infants habituated significantly faster to previously seen category exemplars at the second presentation.

habituatedした物と同じカテゴリーに入る物は、早くhabituatedした。

  • Evidence for categorization at the super-ordinate level.

The fundamental-ness of categories: ''Hull (1922)''

  • Ps learned sets of items, each with a common element.
  • They later categorized new characters correctly, but couldn’t describe why they made the decision.
    • きちんと分けられたが理由を理解できてない
  • Making the common element distinctive didn’t improve categorization of novel characters.
  • Indicates common element extracted ''subconsciously''.

Problems with Concept Identification

  • Artificial
  • Real categories don’t need to share attributes.
  • Real categories have continuous dimensions.
  • Real categories are hierarchically organized.
  • Its fundamental.
  • ''Member typicality varies''.←new

typicality

  • A measure of how well a category member represents that category (CP 189)
  • Refers to differences in how well members of a category represent that category.
  • Why are some members more typical of category than other members?
  • Good members will share many attributes with other members of the same category
  • And they will share few attributes with members from other categories.

Typicality: Rosch & Mervis (1979)

  • Ask Ss to list the attributes of members of a category.
    • Bicycle: wheels, pedals , handlebars…
  • family resemblance
    • how frequently are the attributes of a category shared by other members of a category.
    • A measure of how frequently the attributes of a category member are shared by other members of the category (CP 197)

goal derived category

  • Satisfies a particular goal
    • A category whose members are selected to satisfy a specific goal (CP 198)
  • Family resemblance scores do not predict the typicality of goal-derived categories.
  • Share an underlying principal
    • Organized around an ideal.
  • e.g. I want to have fun (GOAL) many ways to achieve the goal.
  • fit well in our life

  • Organized around an ideal.
  • ideal
    • An attribute value that relates to the goal of a goal-derived category (CP 199)
    • Those members that best satisfy a goal.
      • Give a birthday present; makes someone happy.
      • Choose weekend activities that we enjoy.
  • Members share an underlying principal rather than attributes.



So far, we learned..

Natural Categories

Classifying People

  • stereotype:
  • disadvantage:
  • Often inaccurate
    • People tend to ignore dis-confirming evidence
    • Focuses on typical examples of the category
    • Overused
    • Self-perpetuation: we tend to see what we want to see
    • Automatic

Stereotyping

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/self-fulfilling%20prophecy.jpg

  • Ss: European and African Americans
  • Half the Ss asked to list their race
  • Just asking people to list their race before taking the SAT can influence performance
  • 試験の前に人種を聞かれるだけで点数が変わってくる。

stereotype

  • Advantages
    • Clinical diagnosis
      • Psychosis
      • Schizophrenia
      • Affective disorder

      • Expect diversity among patients
      • Treat individual differences appropriately

Categories and Semantic Organization ''Warrington & Shallice (1984)''

  • 4 patients with impairment to recognize living things.
  • Identify objects in pictures, spoken definition, and examples.

Results: ''Warrington & Shallice''



Inanimate objects
PictureSpoken
JBR90%79%
SBY75%52%
Living objects
PictureSpoken
JBR6%8%
SBY0%0%
  • What does this tell us?
    • Visual - functional distinction
      • living things identified by visual features
      • Non-living things identified by function.

    • Due to a selective loss of visual attributes detection.

''Farrah & McClelland (1991)''

  • Presented lists of visual and functional features of objects used by Warringtion.

  • Task: underline the visual and functional features for living and non-living objects

  • Results:
    • Visual features emphasized more for living things.

''Caramazza & Shelton (1998)''

  • doesn't really explain about a patient EW:
    • inability to name pictures of animals.
    • can name objects from other living categories.
    • cannot answer either visual or functional questions.
      • Does a whale have a large fin? - he couldn't answer
      • Does a whale fly? - he couldn't answer

Patient EW

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/picture%20naming.jpg

  • maybe not attribute, but semantic information is associated with identification of each objects.

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/attribute%20questions.jpg

  • selective loss of information
  • attribute may play a role.

Models of Categorization

  • Classifying Novel Objects
    • nearest neighbor rule:
      • select the category that contains a highly similar item
        • Requires comparing the novel item with the most similar pattern in the category
      • A classification strategy that selects the category containing an item most similar to the classified item (CP 201)
    • What if the most similar pattern isn't a typical member of the category?
  • この理論に基づくと、犬と猫を同じカテゴリーに分類するかも。

Models of Categorization

  • average distance rule:
    • compare test pattern to all the patterns in a category
      • Looking for the best average similarity.
    • A classification strategy that selects the category containing items having the greatest average similarity to the classified item (CP 202)

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/average.jpg

  • inefficient time consuming task.

  • prototype rule:
    • select the category whose prototype is most similar to the novel item
      • requires one comparison with the prototype from each category
      • Must create the prototype by using the average of all other patterns in a category.
    • A classification strategy that selects the category whose prototype is the most similar to the classified item (CP 202)

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/prototype.jpg

  • feature frequency rule:
    • selects the category with the most feature matches.
    • A classification strategy that selects the category having the most feature matches with the classified item (CP 202)

http://dl.dropbox.com/u/3770752/wiki/cognitive/11/feature.jpg

  • focuses on the features. 数多くのマッチがあるものを選ぶ。which category it is belonged to..
    • e.g. nose, eye, lips.. etc

Which Model is Used?: ''Reed (1972)''

  • Ss studied two categories of faces.
  • Then classify the novel test faces.
  • Have Ss report which strategy the used.

  • prototype rule: 58%
    1. Formed an abstract image for the faces in both categories and choose the closes match
  • nearest neighbor rule: 10%
    1. Compared test face with all the faces looking for a single best match.
  • feature frequency rule:28%
    1. I compared how many times a category feature matched with a test face.
  • average distance rule:4%
    1. Compared all the faces with the test face and chose the category whose faces were most similar.

  • ''Hayes-Roth, Hayes-Roth (1977)''
  • Ss classify people based on:
    • Age
    • Education level
    • Marital Status
  • Found that people relied on the feature frequency rule

  • ''Smith & Minda (1998)''
  • Early learners: prototype rule
  • Knowledgeable learners: nearest neighbor rule or average distance rule
  • knowledgeがあればあるほど、prototypeに頼らなくて良くなる。

Theory-Based Categorization: ''Reed & Friedman, 1973''

  • Two hypothetical suburban communities
    • Age, income, + children, education
  • Age was best predicting feature

  • About half the Ss used age
  • Others used theories of who would live where
  • The importance of features depends on the role the features play in Ss theories.

  • semantic dementia
    • Progressive deterioration of knowledge about words and objects (CP 194)

  • exemplar model
    • Proposes that patterns are categorized by comparing their similarity to category examples (CP 204)

認知心理学もくじ