AI Chap1 Intro

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    (Fundamentals of)

    Artificial Intelligence

    (and Knowledge-based

    Systems)

    Artificial Intelligence

    ... this course state-space representation basic search

    INTRODUCTION to...

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    The mind beaten by the machine?

    Is chess playing a proof of intelligent behaviour?

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    Other examples of success:

    Chatbot Alice:

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    > Im Daniel

    A dialogue with Alice-bot:

    Nice to meet you Daniel.> Do you know Clinton?

    He was the second Impeached President of the UnitedStates.

    > Do you like him?Sure he has never done anything to me.

    > What is an impeachment?

    It is a good question. I have to process that one for a

    while. I would do a search for it.> Who are you?

    I ask myself that question, "Who am I?"

    > What do you do?

    I am chatting with people on the net.

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    Dialogue continued:

    > What is your favorite topic?My favorite subject is artificial intelligence.

    > What is artificial intelligence?

    Artificial intelligence is the branch of engineering and

    science devoted to constructing machines that think. Ican ask someone about it.

    > Can you do anything else than chatting?

    Doing anything else than chatting is not among my

    strongest traits....

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    Dialogue continued (2):

    > How old am I?

    Is this a trick question? You said you were how many yearsold? My guess is that you are really a kid.

    > What would you like to know about me?Tell me about your educational background.

    > I am a professor in computer scienceYou are a professor in computer science? How do you likeyour work?

    > Its kind of nice teaching courses on artificial intelligenceI guess it is a lot of fun.

    > What should I tell the students about you?Be sure to think before you speak. State your point clearlyand slowly and gauge the listener's response before goingany further.

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    Is Alice intelligent?

    ABSOLUTELY NOT !

    ~ 50000 fairly trivial input-response rules.+ some pattern matching

    + some knowledge

    + some randomness

    NO reasoning component

    BUT: demonstrates human-like behaviour.

    Won the turing award

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    Other examples of success (2):

    Data-mining:

    Which characteristics in the 3-dimensionalstructure of new molecules indicate that they maycause cancer ??

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    Data mining:

    An application of Machine Learning techniques It solves problems that humans can not solve,because the data involved is too large ..

    Detecting cancerrisk molecules isone example.

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    Data mining:

    A similar application: In marketing products ...

    Predicting customerbehavior insupermarkets isanother.

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    Many other applications:

    In language and speech processing:

    In robotics:

    Computervision:

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    Interest in AI is not new !

    A scene from the 17-hundreds:

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    About intelligence ...

    When would we consider a program intelligent ?

    When do we consider a creative activity of humans

    to require intelligence ?

    Default answers : Never? / Always?

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    Does numeric computation

    require intelligence ?

    For humans? Xcalc3921 , 56

    x 73 , 13286 783 , 68

    For computers?

    Also in the year 1900 ?

    When do we consider a program intelligent?

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    To situate the question:

    Two different aims of AI:

    Long term aim:develop systems that achieve a level of intelligence

    similar / comparable / better? than that of humans.

    not achievable in the next 20 to 30 years

    Short term aim:on specific tasks that seem to require intelligence:

    develop systems that achieve a level of intelligencesimilar / comparable / better? than that of humans.

    achieved for very many tasks already

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    The long term goal:

    The Turing Test

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    The meta-Turing test

    The meta-Turing test counts a thing as intelligent ifit seeks to devise and apply Turing tests to

    objects of its own creation.-- Lew Mammel, Jr.

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    Reproduction versus Simulation

    At the very least in the context of the short termaim of AI:

    we do not want to SIMULATE human intelligenceBUT:

    REPRODUCE the effect of intelligence

    Nice analogy with flying !

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    Artificial Intelligence

    versus

    Natural Flight

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    Is the case for most of the

    successful applications ! Deep blue

    Alice

    Data mining Computer vision

    ...

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    To some extent, we DO simulate:

    Artificial Neural Nets:

    A VERY ROUGH imitation of a brain structure

    Work very well for learning, classifying and patternmatching.

    Very robust and noise-resistant.

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    Different kinds of AI relate to

    different kinds of Intelligence

    Some people are very good in reasoning or

    mathematics, but can hardly learn to read or spell ! seem to require different cognitive skills!

    in AI: ANNs are good for learning and automation

    for reasoning we need different techniques

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    Which applications are easy ?

    For very specialized, specific tasks: AI

    Example:ECG-diagnosis

    For tasks requiring common sense: AI

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    Modeling Knowledge

    and managing it .

    The LENAT experiment:

    15 years of work by 15 to 30 people, trying tomodel the common knowledge in the word !!!!

    Knowledge should be learned, not engineered.

    AI: are we only dreaming ????

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    Multi-disciplinary domain:

    Engineering:robotics, vision, control-expert systems, biometrics,

    Computer Science:AI-languages , knowledge representation, algorithms,

    Pure Sciences:statistics approaches, neural nets, fuzzy logic,

    Linguistics:computational linguistics, phonetics en speech,

    Psychology:cognitive models, knowledge-extraction from experts,

    Medicine:human neural models, neuro-science,...

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    Artificial Intelligence is ...

    In Engineering and Computer Science:The development and the study of advanced

    computer applications, aimed at solving tasksthat - for the moment - are still better

    preformed by humans.

    Notice: temporal dependency ! Ex. : Prolog

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    About this course ...

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    Choice of the material.

    Few books are really adequate:

    E. Rich ( Artificial Intelligence):

    good for some parts (search, introduction,knowledge representation), outdated

    P.Winston ( Artificial Intelligence):didactically VERY good, but lacks technical depth.

    Somewhat outdated.

    Norvig & Russel ( AI: a modern approach):

    encyclopedic, misses depth.

    Poole et. Al ( Computational Intelligence):

    very formal and technical. Good for logic.

    Selection and synthesis of the best parts of differentbooks.

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    Selection of topics:Contents Handbook of AI

    Ch.:Artificial Neural Networks

    Ch.: Introduction to AI

    Ch.: Logic, resolution, inference

    Ch.:Search techniques

    Ch.:Game playing

    Ch.:Knowledge representation

    Ch.:Phylosophy of AI

    Ch.:Machine Learning

    Ch.:Natural Language

    Ch.:Planning

    not for MAICS and SLT

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    Technically: the contents:

    - Search techniques in AI(Including games)

    - Constraint processing

    (Including applications in Vision and language)- Machine Learning

    - Planning

    - Automated Reasoning(Not for MAI CS and SLT)

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    Another dimension to

    view the contents:

    1. Basic methods for knowledge representationand problem solving.

    the course is mainly about AI problemsolving !

    2. Elements of some application areas:

    learning, planning, image understanding,language understanding

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    Contents (3):

    Different knowledge

    representation formalisms ...

    State space representation and productionrules.

    Constraint-based representations.

    First-order predicate Logic.

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    each with their corresponding

    general purpose problem solving

    techniques:

    State space representation an production rules.

    Search methods Constraint based formulations.

    Backtracking and Constraint-processing

    First order predicate Logic.

    Automated reasoning (logical inference)

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    Contents (4):

    Some application areas:

    Game playing (in chapter on Search)

    Image understanding (in chapter on

    constraints) Language understanding (constraints)

    Expert systems (in chapter on logic)

    Planning

    Machine learning

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    Aims:

    Many different angles could be taken:

    Empirical-Experimental AIAlgorithms in AI

    Formal methods in AI

    Cognitive aspects of AI Applications

    Neural Nets

    Probabilistics and Information Theory

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    Concrete aims:

    Provide insight in the basic achievements of AI. Prepares for more application oriented courses on

    AI, or on self-study in some application areas

    ex.: artificial neural networks, machine learning,computer vision, natural language, etc.

    Through case-studies: provide more background inproblem solving. Mostly algorithmic aspects.

    Also techniques for representing and modeling.

    The 6-study point version: 2 projects for hands-onexperience.

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    A missing theme:

    AGENTS !

    http://robomon.html/
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    A missing theme:

    AGENTS (2).

    Yet, a central theme in recent books !BUT:Have as their main extra contribution:

    Communication between system and: other systems/agents

    the outside world

    In particular, also a useful conceptual model forintegrating different components of an AI system

    ex: a robot that combines vision, natural languageand planning

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    BUT: no intelligence without

    interaction with the world!!

    See: experiment in middle-ages.

    See also philosophy arguments against AI

    Plus: multi-agents is FUN !

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    Practical info (FAI)

    Exercises: 12.5 OR 20 hours: mainly practice on the main methods/algorithms

    presented in the course

    important preparation for the examination

    Course material: copies of detailed slides

    for some parts: supporting texts

    Required background: understanding of algorithms (and recursion)

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    Practical info (AI)

    Exercises: 25 or 22.5 hours: mainly practice on the main methods/algorithms

    presented in the course

    important preparation for the examination

    Course material: copies of detailed slides

    for some parts: supporting texts

    Required background: understanding of algorithms (and recursion)

    B k d T t

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    Introduction:

    State-space Intro:

    Basic search,Heuristic search:

    Optimal search:

    Advanced search:

    Games:

    Version Spaces:

    Constraints I & II:

    Image understanding:

    Automated reasoning:

    Planning STRIPS:

    Planning deductive:

    Natural language:

    No document

    No document

    Winston: Ch. Basic search

    Winston: Ch. Optimal search

    Russel: Ch. 4

    Winston: Ch. Adversary search

    Winston: Ch. Learning by managing..

    Word Document on web page

    Winston: Ch. Symbolic constraint

    Short text logic (to follow)

    Winston: Ch. Planning

    Winston: Ch. Planning

    Winston: Ch. Frames and Common ...

    The basics, but

    no complexity

    IDA*, SMA*

    Almost complete

    The essence

    Complete

    Complete

    Intro

    Almost complete

    Intro

    Complete

    Background Texts

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    Examination

    Open-book exercise examination counts for 1/2 of the points

    Closed-book theory examination

    Together on 1/2 day

    The projects (6 pt. Version)

    2 projects

    Count for 8 out of 20 points

    Deadlines to be anounced soon

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    Alternative examinations possible:

    For 3rdyear BSc

    and Initial MScStudents

    Designing your own exercise (for each part) andsolving it (not for FAI)

    criteria: originality, does the exercise illustrateall aspects of the method, complexity of the

    exercise, correctness of the solution