The Language Instinct

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The Language Instinct

• Talking Heads

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Construing the Meaning

• Comprehension involves a process of finding
  subjects, verbs, objects and so on, that it takes
  place unconsciously
• A dog bites a man.
• A man bites a dog.
• A man is bitten by a dog.

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A definition of parser

• Parser - the mental programme that analyses
  sentence structure during language comprehension

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Components of a Simple Sentence

• S NP VP
• NP det N
• VP V NP
• N boy, girl, dog, cat, ice cream, candy, hot
  dogs, etc.
• V eats, likes, bites, etc.

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The dog likes ice cream

• det
• the...

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• NP
• det N
• the...
  

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The dog likes ice cream

• S
• NP VP
• det N
• the...

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Difficulties with understading long, complicated
phrases

• Memory - one has to keep track of phrases that
  need particular words to complete them
• Decision-making - when a word or phrase belongs
  to two different cagetories (eg. VP, NP), one has
  to decide which to use to build the next branch
  of the tree

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Memory

• Short term memory is the key tool in human
  information processing
• Only a few items - plus or minus seven can be
  held in mind at once
• The items are immediately subject to fading or
  being overwritten

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Memory

• Memory-stretching sentences
• Onion sentences

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The Memory-Stretching Sentence

• He gave the girl that he met in New York while
  visiting his parents for ten days around
  Christmas and New Years the candy.

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• He gave the candy to the girl that he met in New
  York while visiting his parents for ten days
  around Christmas and New Years.

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Onion Sentences

• The dog the stick the fire burned beat bit the
  cat.
• The malt that the rat that the cat killed ate lay
  in the house.
• If if if it rains it pours I get depressed I
  should get help.

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Onion Sentences

• Onion sentences show that a grammar and a parser
  are different things
• A person can recognise constructions that he or
  she can never understand.

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• Can you do addition? the White Queen asked.
  Whats one and one and one and one and one and
  one and one and one and one and one?
• I dont know, said Alice. I lost count.
• She cant do Addition, the Red Queen
  interrupted.

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• The human sentence parser keeps track of where it
  is in a sentence by writing a number in a slot
  next to each phrase type on a master checklist.
• When a type of a sentence has to be remembered
  more than once - so that both it and the
  identical type of phrase it is inside of can be
  completed in order - there is not enough room on
  the checklist for both numbers to fit, and the
  phrases cannot be completed properly.

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• The cheese that some rats that were chased by the
  cats that I feed ate turned out to be rancid.

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Decision Making

• Many words have more than one lexical entry (e.g.
  one can be either a determiner or a noun) thus a
  parser has to decide which option fits a sentence
  the best
• Phrases can also go inside either a NP or a VP -
  so that it also may lead to ambiguities

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• The plastic pencil marks...
• The plastic pencil marks were ugly.
• The plastic pencil marks easily.

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• Ingres enjoyed painting his models nude.
• Visiting relatives can be boring.
• Vegetarians dont know how good meat tastes.
• I saw the man with the binoculars.

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The Two Ways of Decision Making

• Breadth-first search
• Depth-first search

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Garden Path Sentences

• Sentences are not laid out with clear markers
  allowing the reader to stride confidently through
  to the end
• Delays Dog Deaf-Mute Murder Trial
• British Banks Soldier On
• Family Leave Law a Landmark Not Only for
  Newborns Parents

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Background Knowledge

• Understanding is not possible unless
  interlocutors share the same background
  assumptions.
• This involves, for instance, cultural background,
  knowledge of recent facts, etc.
• Woman Im leaving you.
• Man Who is he?

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• Thank you for your attention