Language and Computers

scarfpocketAI and Robotics

Oct 24, 2013 (3 years and 7 months ago)

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LELA300431

Language and Computers

Harold Somers

Professor of Language Engineering

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Getting computer to handle language in a natural way


As part of interface with user (eg alternatives to keyboard/mouse
input, text output, support for the disabled)


consulting databases to get information (e.g. library catalogue, train
timetable, banking)


As a task in itself: specifically linguistic purposes (e.g. dictation,
translation, summarizing, report writing, language teaching)


Using computer to “do” linguistics


Synonyms (or components?)


Natural Language Processing


Computational Linguistics


Language Engineering


Basic tools, techniques and models


Applications

Computers and Language?

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Syllabus


Survey of applications


Elements of language, levels of linguistic processing


Sound (speech recognition, synthesis)


Writing (OCR, handwriting, character sets, spelling)


Words (lexicon, morphology)


Sentences (syntax)


Semantics, Pragmatics


Branches of language/linguistics


Psycholinguistics and AI


Applied linguistics (teaching, translation)


Information retrieval


Or:
your choice of anything else relevant
(historical, socio, etc.)


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Mon 10am Newman/G16

Fri 10am AlanTuring/G205

1. Introduction


Sept 24, 28

Introduction, explanation of syllabus

What makes language hard for
computers?

Applications: overview

2. Phonetics


Oct 1, 5

Speech recognition

Speech synthesis

3. Writing


Oct 8, 12

Character sets, Unicode, input methods

Spell checkers, grammar checkers

4. Words


Oct 15, 19

Dictionaries, Thesauri

WordNet

5. Morphology


Oct 22, 26*

Morphology

Tagging


READING WEEK

6. Syntax


Nov 5, 9

Parsing I

Parsing II

7. Semantics,Pragmatics


Nov 12, 16

Dialogue understanding

Text generation,

Cooperative responses

8. Branches


Nov 19, 23

Psycholinguistics: language and AI

Applied linguistics: CALL

9. Applied linguistics


Nov 26, 30*

CALL

Translation aids

10. Translation


Dec 3, 7

Machine translation I

Machine Translation II

11. Information retrieval


Dec 10, 14

Text retrieval; Summarization

Question answering, text mining

* These lectures to be rearranged due to HS’s absence

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Assessment

Examination:

50 multiple choice (or short phrase) answers


Essay


3000 word essay due in at the start of the exam period


Choose a particular NLP application, and explain the difficulties that
natural language poses to the computer, and how (or whether) they are
addressed.


How is the study of language relevant to NLP? Focus on one or two
areas of NLP only.


Choose one branch of language study (eg historical, sociolinguistics,
psycholinguistics, child language, applied linguistics, etc.) and discuss
what role the computer, and in particular computational linguistics,
could play.

(Note that
all

involve taking lectures as starting point, and going into more
detail, based on your own “research”)

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What
is

NLP?

Language and

Linguistics

Psychology

Electrical

Engineering

Computer

Science

NLP

Artificial

Intelligence

Language

Engineering

HCI

Signal

Processing

Phonetics

Philosophy

Logic

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Language and AI


“language ability” is an integral part of
Artificial Intelligence, which relates to
robotics


Computers in SciFi use language readily:
how realistic is this? What are the
problems?


HAL in “2001: A Space Odyssey” (1968)

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How realistic is HAL?

Non
-
linguistic functions include...



monitoring and controlling the spaceship



playing chess



vision



general reasoning about the world …



especially this particular mission

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HAL’s use of language

He has to use language to communicate with
the crew, including ...


chatting sociably


discussing general and specific conditions
in the spaceship


understanding commands


initiating conversations, whether “work” or
“play”

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What is language?


spoken vs. written language


speaker vs. hearer = production vs. analysis


different levels of language


different functions of language

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Computer speech


for natural
-
sounding speech, computer must
get individual sounds right, but also
combine them correctly


intonation


stress (pitch, loudness, length)


pace (pauses can be significant)

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Speech understanding


signal processing (acoustic physics)


separating speech from background noise


recognizing individual speech sounds
(humans can make very fine distinctions)

It’s hard to wreck a nice beach

What dime’s a neck’s drain to stop port?


variability in human voices

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Problems with language in general


Words are ambiguous (
bank
,
round
,
take
)


Sentences are ambiguous

The chicken is ready to eat

Visiting relatives can be boring

End to free school looms

The man saw the girl with a telescope

Remove bulb, cover, and replace

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Pragmatic problems


We don’t always say what we mean

Can you pass the salt?

It’s cold in here, isn’t it?

I’m sorry (= Say it again)

Do you want some more? You’re alright.


We don’t always mean what we say

It’s raining cats and dogs

I could murder a sandwich

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Solutions


Linguistics (“grammar”)


can often tell us which interpretations are
possible, including limited aspects of
meaning, e.g.
The man saw the girl with a hat


Restricted domain: if we know what the
subject is, a lot of ambiguity disappears



Context



Real
-
world knowledge

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Next up


A whistle
-
stop tour of applications and what
they involve


Then down to business!