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    Artificial Intelligence

    Introduction

    Fall 2008

    professor: Luigi Ceccaroni

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    Instructors

    Luigi Ceccaroni

    Omega building - Office 111

    [email protected] Nria Castell Ario

    FIB building - Second floor

    [email protected]

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    Course description

    This course introduces:

    Representations

    Techniques

    Architectures

    This course also explores applications of:

    Rule chaining

    Heuristic search

    Constraint propagation

    Constrained search

    Decision trees

    Knowledge representation

    Knowledge-based systems Natural-language processing

    It accounts for 7.2 credits of work load, distributed as:

    3.6 credits for theory

    2.4 for recitations

    1.2 for laboratory

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    Web pages

    http://www.lsi.upc.es/~bejar/ia/ia.html

    http://www.lsi.upc.edu/~luigi/MTI/AI-2008-fall/ai.html

    http://raco.fib.upc.es/

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    Background

    Students need the following knowledge (at theundergraduate level) to appropriately follow the course: English language

    Propositional and predicate logic; capacity to formulate a

    problem in logical terms Logical inference; strategies of resolution; capacity to solveproblems by resolution

    Graph and tree structures; algorithms for search in trees andgraphs

    Computational complexity; calculation of algorithm execution's

    cost There are assignments that expect students to be able

    to read and write basic Java. This is the only formal pre-requisite.

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    Aim of the course

    The general objectives of the course can besummarized as: To identify the kind of problems that can be solved

    using AI techniques; to know the relation between AI

    and other areas of computer science. To have knowledge of generic problem-solving

    methods in AI.

    To understand the role of knowledge in present IA; toknow the basic techniques of knowledge

    representation and their use. To be able to apply basic AI techniques as support

    for the solution of practical problems.

    To be able to navigate the basic bibliography of AI.

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    Topics

    [ 1.] Search

    [1.1] Problem representation

    [1.2] Search in state space [1.3] Uninformed search

    [1.4] Informed search (A*,IDA*, local search)

    [1.5] Games

    [1.6] Constraint satisfaction

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    Topics

    [2.] Knowledge representation and

    inference

    [2.1] Methodologies for knowledgerepresentation

    [2.2] Rule-based systems

    [2.3] Structured representations: frames and

    ontologies

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    Topics

    [3.] Knowledge-based systems

    [3.1] Definition and architecture

    [3.2] Expert systems [3.3] Knowledge engineering

    [3.4] Approximate reasoning

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    Topics

    [ 4.] Natural language

    [4.1] Textual, lexical and morphological

    analyses

    [4.2] Levels of natural language processing

    [4.3] Logical formalisms: definite clause

    grammars

    [4.4] Applications and current areas ofinterest

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    Topics

    [ 5.] Machine learning

    [5.1] Decision trees

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    Bibliography

    There are no required readings, apartfrom the course lecture notes. Additionalreading can be found in the following text:

    Russell, Stuart J. and Peter Norvig

    Artificial intelligence: a modern approach. 2nd

    edition Upper Saddle River, NJ: Prentice Hall, 2002

    ISBN: 0137903952.

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    What is AI?

    There is no single definition, but severalapproaches, that Russell-Norvigsummarize in four main ones.

    These approaches follow different pointsof view.

    Their influences are diverse (Philosophy,

    Mathematics, Psychology, Biology...). Their fields of application are ample and

    interrelated.

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    Approaches to AI

    Systems that act like humans

    The study of how to obtain that computers perform tasks atwhich, at the moment, people are better (Rich and Knight, 1991)

    Systems that think like humans

    The effort to make computers think... machines with minds in thefull and literal sense (Haugeland, 1985)

    Systems that think rationally

    The study of the mental faculties through the study ofcomputational models (Charniak and McDermott, 1985)

    Systems that act rationally

    The effort to explain and emulate the intelligent behavior interms of computational processes (Shalkoff, 1990)

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    Other approaches to AI

    Good Old-Fashioned Artificial Intelligence

    (GOFAI) (Douglas Lenat: Cyc) Cramming a computer full of knowledge about the

    real world and methods to manipulate it

    Intelligence intimately tied up with having and being

    able to use knowledge

    Its worth to go to school

    Robotic insects example

    Legs controlled by a central computer that has a detailed 3D

    map of the terrain and knows all the relevant laws of physics

    and strategies

    15

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    Other approaches to AI

    Learning through experience (Rodney

    Brooks: Cog, Kismet)

    Machines that experience the world in muchthe way human beings do

    You can learn stuff on your own

    Robotic insects example

    Each leg containing a small circuit that tells itabout basic movements

    All local computation physically coupled through

    the body, with gait emerging spontaneously from

    circuits interaction 16

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    Areas of work in AI

    Theory

    Philosophy

    Applications

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    Turing test

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    The Chinese room (John Searle)

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    Eliza (1966)

    Conversation with ELIZA

    E> Hello. I am ELIZA. How can I help you?

    P> I am feeling sad.

    E> I am sorry to hear you are sad.P> I had some nightmares tonight.

    E> You say you had some nightmares tonight?

    P> Yes, my dreams are worrying me.

    E>What does that dream suggest to you?

    P> Thrill, scare.E> I am not sure I understand you fully.

    P> My dreams annoy me.

    E> Do you dream often?

    P> Yes, daily.

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    Lost in translation

    English Russian (or Spanish) English

    The spirit is willing, but the flesh is weak

    ,

    The vodka is good, but the meat is rotten

    (Actually: Spirit is willingly ready, but flesh is weak or

    The alcohol is arranged, but the meat is weak)

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    Autonomous robots

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    Personalization,

    recommendation

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    US District Court judge

    John E. Jones III

    Proponents of intelligent design arguedthat their supposedly scientific alternativeto evolutionary theory should be

    presented in biology classes.

    An objective student can reasonably infer

    that the schools favored view is areligious one, and that the school isaccordingly sponsoring a form of religion.

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    One book

    What if I want to read just one book about

    artificial intelligence?

    Darwin's Dangerous Idea by Daniel Dennett

    In favor of materialistic Darwinism

    Victims: Noam Chomsky, Roger Penrose, John

    Searle and, specially, Stephen Jay Gould