what is ai?suraj.lums.edu.pk/~cs331w04/slides/lecture1.pdf · scope of ai based techniques main...

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CS 231: Dr M M Awais (LUMS)

What is AI?

∇ Computer based solution of complex problems through the application of processes that are analogous to the

Human Reasoning Process

CONTROVERSIAL ISSUE(How to Define AI)

CS 231: Dr M M Awais (LUMS)

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CS 231: Dr M M Awais (LUMS)

Can Ever A Computer Be Made That Actually “THINKS”

Lets Define What Intelligence is.

IDEAS?

Is it a Learning Process?Is it a Reasoning Process?Is it a Thinking Process?

CS 231: Dr M M Awais (LUMS)

AN OPNION

Intelligence isReasoning + Learning

Intelligent Beings

Intelligent Systems

(Systems that try to mimic reasoning and learning abilities)

- Establishes Relationships- Perception and Comprehension- Generalization Ability

- Memory- Differentiating

Chair vs TableSpoon vs Fork

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CS 231: Dr M M Awais (LUMS)

CS 231: Dr M M Awais (LUMS)

Concepts of AI

Strong AI?Consciousness - “is some complicated computation”

Brains Are Computers of MEAT?

“Computers can achieve or even exceed all Human Capacities once high computational speeds are achieved”

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CS 231: Dr M M Awais (LUMS)

Weak AI?

Computation Consciousness

Brain has ingredients that are

∇ Non - computational

∇ Simulating consciousness is not possible

Computational + Non Computational

BRAIN

CS 231: Dr M M Awais (LUMS)

Scope of AI Based Techniques

Main focus Problems that do not have algorithmic solutions

Vague, uncertain and poor-defined systems

Systems with decision - making problems

(Examples?)

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CS 231: Dr M M Awais (LUMS)

CS 231: Dr M M Awais (LUMS)

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CS 231: Dr M M Awais (LUMS)

Example Tasks

Game Playing∇ Rules are well defined∇ Formalisation is easy

Automated Reasoning∇ Theorem proving∇ Formal logic/ knowledge representation.

Expert SystemsMimic experts such as doctors

Coding

Knowledge Diagnostic

Experts

Experts

CS 231: Dr M M Awais (LUMS)

Natural Language Processing

∇ Computer learn human languages

Examples:-Leobner Prize Context (Started in 1991).

Rules:-∇ Judges rate the response of the computer programs and try to

find out whether it is human or a computer.

1996 - a program fooled 5 judges out of 10.

A Fragment is Presented ……..)

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CS 231: Dr M M Awais (LUMS)

CS 231: Dr M M Awais (LUMS)

Planing And Robotics

∇ Artificial Pets.

∇ Efforts to make “machines”- Responsive

- Flexible

e.g.,

Human Machine

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CS 231: Dr M M Awais (LUMS)

Turing TestQ

A

Computer

CS 231: Dr M M Awais (LUMS)

Objections :- Turning Test

Most AI Programs Are Not Flexible In Nature

May Not Be Able to Answer Emotional Questions

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CS 231: Dr M M Awais (LUMS)

Knowledge Representation And Preference

Key AssumptionPhysical Symbol System’s Hypothesis

Examples:-∇ black (mybook) denotes:

my book is black∇ clear (way)

way is clear

CS 231: Dr M M Awais (LUMS)

Physical Symbol System Hypothesis

Consists ofSet of entities (Symbols)Expressions (Joint symbols)Processes (Joint expressions)

Symbols Expressions Processes

“A physical symbol system has the necessary and sufficient means for general intelligent action”

(Through Learning)

CreationModificationDestructionProduction

Of Processes(new)

outputs

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CS 231: Dr M M Awais (LUMS)

Importance of Semantics

∇ If semantic is wrong proper conclusion is not reached

Init. Fact Formal Fact(Mapping Due to Semantics)

Conclusion Formal Reasoning

CS 231: Dr M M Awais (LUMS)

Knowledge Representation Languages

• A) Representational Adequacy

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CS 231: Dr M M Awais (LUMS)

(b) Naturalness

Captures the structure of knowledge in an obvious way

Fact: If you are tired you should rest

Repn 1. If (x, t, s)2. If condition (x, tired)

Then cure (x, sleep)(rest)

(c) Inferential AdequacyShould be able to deduce new facts from existing knowledge

e.g., Is ‘Y’ president of PAKISTAN?

CS 231: Dr M M Awais (LUMS)

(d) Inferential Efficiency

The speed of outputting INFERENCES

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CS 231: Dr M M Awais (LUMS)

CS 231: Dr M M Awais (LUMS)

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CS 231: Dr M M Awais (LUMS)