Doğal Dil İşleme - Giriş

Yılmaz Kılıçaslan

Sunu Planı

· Bugün,– Ne yapacağız?– Nasıl yapılır?– Niçin yapmalıyız?

sorularına yanıt arayarak derse giriş giriş yapacağız.

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Ne Yapacağız?

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· Dil· Zihin· Gerçeklik

· Bilgisayarlı· Kuramsal· Felsefi

üzerineçalışmalaryapacağız.

· Edebiyat· Yazım kuralları· Dil ağızları vs.

üzerine çalışmayacağız.

Dilin anlamı vardır: totoloji

· Dilin varoluş gerekçesi anlam kodlamaktır.

· Bir dil eylemi, ancak birilerinin birşeyleri anlamasını sağladığı zaman başarıya ulaşır.

· Anlamını bilmediğimiz sesler, dinleyen için gürültüden ibarettir.

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Anlamın anlamı: paradoksal

· We are all homo significans. However, ...

· “[though] it is tautological that meaningful expressions are just that, meaningful, it has proven extremely difficult to say much more about this property of meaning” (p. 3). (Barwise and Perry 1999)

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Anlam üç öğeli bir ilişkidir

· Smoke means fire.· Fire causes smoke.· Smoke means fire to us. · *Fire causes smoke to us.

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Anlamın üç öğesi

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WORDS REALITY

MINDS

LINGUISTIC MEANING

Words can be constituents of meanings.

Donald Davidson

The external world accommodates meanings.

Jon Barwise

Meaning’s natural home is the mind.

John locke

VIEWS OF REALITY:

1.ARISTOTELIAN

2. PLATONIC

3 NOMINALIST

4. CONCEPTUALIST

5. SOLIPSIST

NATURAL WORLD

REALM OF IDEAS

NO STRUCTURE

MIND

NO REALITY

SOURCE OF STRUCTURE:

İşaretler: anlam üretme araçları

· As Chandler (1984) points out, we, as homo significans, make meanings through our creation and interpretation of signs.

· Some philosophers, such as Peirce, argue that we think only in signs.

· Piaget goes one further step and claims that there is no difference between sign usage and (conceptual) thought.

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Saussurean SignA dyadic matrix excluding the non-mental

· The signifier is the form which the sign takes and the signified is the concept it represents.

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· A sign is always a combination of these two.

Peircean Sign A triadic structure with an exit to external reality

A sign, or representamen, is something which stands to somebody for something in some respect or capacity. It addresses somebody, that is, creates in the mind of that person an equivalent sign, or perhaps a more developed sign. That sign which it creates I call the interpretant of the first sign. The sign stands for something, its object. (Peirce 1931)

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Properly speaking, semiosis starts because a representamen is opaque, but, when the representamen is transparent semiosis becomes a blind process. (Peirce 1931)

Typology of Signs indices, icons and symbols

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Icon: a mode in which the signifier is perceived as resembling or imitating the signified (recognizably looking, sounding, feeling, tasting or smelling like it): e.g. a portrait, a cartoon, a scale-model, metaphors, 'realistic' sounds in 'programme music', sound effects in radio drama, a dubbed film soundtrack, imitative gestures.

Index: a mode in which the signifier is directly connected in some way (physically or causally) to the signified: e.g. 'natural signs' (smoke, thunder, footprints, echoes and flavours), medical symptoms (pain, a rash, pulse-rate), measuring instruments (weathercock, thermometer, clock), 'signals' (a knock on a door, a phone ringing), pointers (a pointing 'index' finger, a directional signpost), recordings (a photograph, a film, video or television shot, an audio-recorded voice), and indexical words ('that', 'this', 'here', 'there').

Symbol: a mode in which the signifier does not resemble the signified but which is fundamentally arbitrary or purely conventional: e.g. language in general (plus specific languages, alphabetical letters, punctuation marks, words, phrases and sentences), numbers, morse code, traffic lights, national flags.

Evolution of alphabets

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Story telling in a neanderthal cave

From pointing to speaking

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From pointing to painting

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Semiotic TriangleSyntax—how signs relate to other signs (e.g. how the word “dog” relates to the other words in the sentence “The dog ate my homework.”)Semantics—study of how signs relate to things (e.g. how the word “dog” relates to an actual dog)Pragmatics—actual use of codes in everyday life; effects of signs on human behavior and how people mold signs and meanings in their actual interaction (e.g. How would the sentence “The dog ate my homework” be used in everyday life? How would my teacher react to it?) 15

Language is a semiotic system.

Subdiciplines of Linguistics

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COGNITIVE LINGUISTICS

SuBFIELDS STUDYING MEANING

SuBFIELDS STUDYING FORM

MORPHOLOGY

PHONOLOGY SYNTAX SEMANTICS PRAGMATICS

ONTOLOGY

ZİHİNSELTEMSİL

GÖZLEM AKIL YÜRÜTME

DIŞ DÜNYA

ALGI

REFLEKS

✓P

✓Q

? P ise Q ✓ P ise Q

✓P

? Q

? P

✓ Q

Tümevarı

mlı

Çıkarı

m

Tümdengeli

mli

Çıkarı

m

Abductive

Çıkarı

m

Mantıksal düşünce tarzları

Deductive and Inductive LogicTwo Types of ‘Scientific’ Reasoning

We tend to think there are two types of reasoning:• deduction, where we move with logical

certainty from general principles to a particular conclusion, as in "all swans are white, this is a swan, so this must be white"

• and induction, where we move from particular observations to general principles, as in "all the swans that have ever been seen are white, so all swans are white"

Deduction is infallible as long as the premises are true, while induction yields probabilities that can always be falsified by events - the black swans that turn up when no one is expecting them.(John Gray, A Point of View: The enduring appeal of Sherlock Holmes, BBC News Magazine, 17 August 2012)

Abductive ‘Logic’The Speculative Reasoning of Sherlock Holmes

• It's not the science of deduction that gives Holmes his power over us, since he doesn't in fact use it. In The Sign of Four, Holmes declares: "I never guess. It is a shocking habit - destructive to the logical faculty." Yet the type of reasoning which Holmes uses in most of Conan Doyle's stories includes a good deal of guesswork.

(John Gray, A Point of View: The enduring appeal of Sherlock Holmes, BBC News Magazine, 17 August 2012)

• The type of reasoning Holmes uses is of another, more conjectural kind - sometimes called abductive reasoning - that can't offer certainty or any precise assessment of probability, only the best available account of events. Importantly, this kind of reasoning can't be practised simply by following rules.

• Holmes notices things other people don't, and then - using a mental agility that involves creative imagination rather than the mechanical application of any method of reasoning - comes up with hypotheses he tests one by one.

A Holistic View of Logic

Dil ve matematik

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COGNITIVE LINGUISTICS

SuBFIELDS STUDYING FORM

MORPHOLOGY PHONOLOGY SYNTAX ONTOLOGY SEMANTICS PRAGMATICS

REPRESENTATION:

SuBFIELDS STUDYING MEANING

MACHINERY:

Strings

Acylic Finite State Automata

Lists

Finite State Automata

Regular Grammars

Regular Expressions

Trees

Push-Down Automata

Context-Free Grammars

Recursive Transition Netwworks

Concept Algebra

Concept Lattices

Logical Induction λ- calculus

Intensional Logic

Turing Machines

Niçin?

· ???

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