IntroAI

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    Introduction to

    IntelligentComputing

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    Text Book:

    ArtificialIntelligenceA Modern Approach

    Stuart Russell & PeterNorvig

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    Intelligence

    Apple Newton Gravity Force No one things like him, why should not

    apple go towards sky which one is pullingtowards earth Earth rotates - force forms

    gravity force. Twin tower attack - secret data Hidden

    in image. Birbol without modification make it as

    small line A long line drawn next to theexisting line. If a machine has brain how it will

    encounter in new situation.

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    Approaches to AI

    Systems that act like humans The study of how to obtain that computers perform tasks

    at which, at the moment, people are better (Rich andKnight, 1991)

    Systems that think like humans The effort to make computers think... machines with

    minds in the full and literal sense (Haugeland, 1985)

    Systems that think rationally The study of the mental faculties through the study of

    computational models (Charniak and McDermott, 1985)

    Systems that act rationally The effort to explain and emulate the intelligent behavior

    in terms of computational processes (Shalkoff, 1990)

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    Definitions (Russell + Norvig)

    Like humans Not necessarily like humans

    Systems that think likehumans

    Systems that think rationally

    Systems that act likehumans

    Systems that act rationally

    Thi

    nk

    A

    ct

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    Human intelligence

    One distinction between these definitions iswhether or not imitating humans is the goal.

    One advantage of imitating humans is thathumans are an easily acknowledged exemplar of

    intelligence.The Turing Test:

    A human interrogator. Communicates with a hiddensubject that is either a computer system or a human. Ifthe human interrogator cannot reliably decide whetheron not the subject is a computer, the computer is saidto have passed the Turing test.

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    Turing Test?

    In 1950 Turing proposed anoperational definition ofintelligence by using a Testcomposed of :

    An interrogator (aperson who will askquestions)

    a computer (intelligent

    machine !!) A person who willanswer to questions

    A curtain (separator)

    A. Turing

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    What is ArtificialIntelligence?

    The computer passes the test of intelligence if a human,after posing some written questions, cannot tell whetherthe responses were from a person or not.

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    Turing test

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    Human intelligenceTuring provided some very persuasive

    arguments that a system passing theTuring test is intelligent.

    However, the test does not provide

    much traction on the question of howto actually build an intelligent system.

    i.e., Turing test is not enough to see

    how a machine acts;We also need to know what internalmental [rational] states it has.

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    Human intelligence

    In general there are various reasonswhy trying to mimic humans mightnot be the best approach to AI.

    Computer Human BrainComputational Units 1 CPU, 108 gates 1011 neurons

    Storage Units 1010 bits RAM

    1011 bits disk

    1011 neurons

    1014 synapses

    Cycle time 10-9 sec 10-3 secBandwidth 1010 bits/sec 1014 bits/sec

    Memory updates/sec 109 1014

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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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    The Chinese room (JohnSearle,1980)

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    Does not necessarily generateUnderstanding

    Human who understands English, equipped

    with a rule book [written in English], variousstacks of paper, some blank, some withindecipherable[hard to read] inscriptions[Words].

    Input to room human finds matchingsymbols in the rule book follows theinstruction.

    From the outside of room system takes

    input in chinese language and generateanswers in chinese language conventionallyintelligent turing

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    Searle argue as follows,

    The person in the room does not

    understand Chinese(given), the rule book stacks of paper does not understandChinese.

    No understanding of Chinese is going on

    Hence, according to Searle, running theright program does not necessarilygenerate understanding.

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    Lost in translationEnglish 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

    orThe alcohol is arranged, but the meat is weak)

    Translation requires general knowledge oflanguage remove ambiguity.

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    Autonomous robots

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    AI inherited many ideas, viewpoints and techniquesfrom other disciplines.AI inherited many ideas, viewpoints and techniquesfrom other disciplines.

    AI Foundations?

    AIAI

    Psychology

    Linguistic

    CS

    Philos

    ophy

    Mathematics

    Theories ofreasoning andlearning

    Theories of logicprobability, decisionmaking andcomputation

    Make AI a

    reality

    The meaning andstructure oflanguage

    To

    investigatehumanmind

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    What is Artificial Intelligence

    To give an answer, the computer would need topossess some capabilities:

    Natural language processing: To communicatesuccessfully.

    Knowledge representation: To store what it knowsor hears.

    Automated reasoning: to answer questions anddraw conclusions using stored information.

    Machine learning: To adapt to new circumstances

    and to detect and extrapolate patterns. Computer vision: To perceive objects.

    Robotics to manipulate objects and move.

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    Goals of AI

    AI began as an attempt to understandthe nature of intelligence,but it has grown into a scientific andtechnological field affecting many aspectsof commerce and society.Solve real-world problems usingknowledge and reasoning.

    Creating new opportunities inbusiness, engineering, and manyother application areas

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    Examples of AI Applicationsystems

    Game Playing

    TDGammon, the worldchampion backgammonplayer, built by GerryTesauro of IBM research

    Deep Blue chess program

    beat world champion GaryKasparov

    Chinook checkers program

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    The decisive game of the match was Game2we saw something that went beyondout wildest [Natural] expectationsThemachine refused to move to a positionthat had a decisive[crucial] short-termadvantage - showing a very human senseof danger.

    Garry Kasparov 1997

    The decisive game.

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    Artificial Intelligence History

    Early AI: (The gestation of Artificial Intelligence)

    1943 McCulloch & Pitts: Boolean circuit model of brain1950 Turing's ``Computing Machinery and Intelligence''1950s Early AI programs, including Samuel's checkers

    program,Newell & Simon's Logic Theorist, Gelernter'sGeometry Engine

    The birth of Artificial Intelligence (1956)

    1956 McCarthy organizes Dartmouth meeting and includesMinsky, Shannon, Newell, Samuel, Simon

    Name ``Artificial Intelligence'' adopted

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    Artificial Intelligence History

    Early enthusiam, great expectations (1952-1969):

    1957 General Problem Solver [Newell, Simon, Shaw @ CMU]1958 Creation of the MIT AI Lab by Minsky and McCarthy1958 LISP, [McCarthy], second high level language (MIT AI

    Memo 1)1963 Creation of the Stanford AI Lab by McCarthy1965 Robinson's complete algorithm for logical reasoning

    A dose of reality (1966-1973):

    1966-74 AI discovers computational complexity

    1966-72 Shakey, SRIs Mobile Robot [Fikes, Nilson]

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    Artificial Intelligence History

    The return of neural networks (1986 - present)

    1988-93 Expert systems industry busts: ``AI Winter''1985-95 Neural networks return to popularity

    AI becomes a science (1987 present)

    1988- Resurgence of probabilistic and decision-theoretic methods

    Computational learning theory

    ``Nouvelle AI'': ALife, GAs, soft computing, emergent

    computing

    Complex Systems or the Science of complexity

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    Rationally wisely, logically

    Omniscience knowing everything [om-ni-science]

    Dichotomy between two things thedichotomy between peace and war [di-cho-tomy]

    Interrogator inquiring

    Exemplar - example Computational calculation

    Wildest - natural

    Mental rational - Internal workings as well as

    external behavior Conscious aware - mindful

    Syntactic - syntax