cs 531: dr m m awais (lums) cs 531: ai cs 331: introduction to ai dr mian muhammad awais room 416...

CS 531: Dr M M Awais (LUMS)

CS 531: AI CS 331: Introduction to AI

Dr Mian Muhammad Awais

Room 416

[email protected]

Robotics and Intelligent Computing (RICE), Group

mailto:[email protected]

mailto:[email protected]


Course DescriptionCourse home page: TBAContacts:lecture notes, tutorials, assignment, grading, office hours, etc.Textbooks: 1) Luger: Artificial Intelligence: Structures and Strategies for Complex Problem-solving Fourth Edition (Available as Reading package)2) S. Russell and P. Norvig Artificial Intelligence: A Modern Approach Prentice Hall, 2003, First or Second Edition (HANDOUTS)Grading:

Quizzes (15%)Practice (15%), Midterm test (30%)Final exam (40%)

Practice Options:•At least 2 Lab Assignments where attendance will be compulsory and will be taken. •Critical reviews of interesting papers•Take Home/In class Assignments (LISP/PROLOG)


TA Support/Office Hours

• TA 1: Umar Faiz ([email protected])

Office hours (TBA, see the website)

• TA 2: TBA

• Instructor Office Hours (room 416):

3 to 4 PM Every day except Friday

[email protected]


Course Outline (Core Areas)Very Basic

• Introduction and Problem Solving (Today’s Lecture)

• Part I:Knowledge Representation

• Part II:Informed Search Methods

• Part III:Planning / Reasoning/Expert Systems

• Part IV:Learning


Course Outline (Specialized Areas)

• To be decide as the course progresses• Some options are:

– NLP

– Speech Processing(On going project at LUMS, 1.0 million, 3 years)

– Agent Technology(Submitted project, 5.9 million, 3 years)

– Imitative Learning (On going project at LUMS, 4.3 million, 3 years)

– Case Based Reasoning

– etc


Course Format• Each Class 100 minutes not 75 minutes• Core Areas:

– Basic stuff, – same as CS 331, – will go through it quickly, – tested with take home assignments, – Midterm and finals will have at least 60% from the core

areas.

• Special Areas: – High level brief discussion, – tested with assignments, quizzes, – maximum of 40% covered in exams


Book Chapters

• Book Chapters and articles will be announced as we go along

• Slides will be available at the website and in the common’s folder

• Details to be announced later


Informal Feedback Mechanism LETS IMPROVE AS WE MARCHLETS IMPROVE AS WE MARCH

• Roughly Every Two Weeks an anonymous questionnaire will be circulated to evaluate the course

• Your comments will be welcomed to improve the course as we go along

(DONOT WAIT TILL THE END)

• Course progress discussion


Questions


TWO PURPOSES of AI.

One is to use the power of computers to augment human thinking,

just as we use motors to augment human or horse power. Robotics and expert systems are major branches of that.

The other is to use a computer's artificial intelligence to understand how humans think.

In a humanoid way. If you test your programs not merely by what they can accomplish, but how they accomplish it, they you're really doing cognitive science; you're using AI to understand the human

mind.Herbert Simon


AI Dimensions

1) Modeling: Thought process/reasoning vs. behavior/action

2) Evaluation:

Success according to human standards vs. success according to an ideal concept of intelligence

rationalityrationality.


What is AI?

Views of AI fall into four categories:

Thinking humanly Thinking rationally

Acting humanly Acting rationally


Thinking humanly

““Can machines think like humans”Can machines think like humans”

• Requires scientific theories of internal activities of the brain, psychological experiments are required

• Studied in Cognitive Modeling


Thinking humanly: cognitive modeling

•1960s "cognitive revolution": information-processing psychology

•Validation Requires

•Predicting and testing behavior of human subjects (top-down)

•Direct identification from neurological data (bottom-up)

•Cognitive Science and Cognitive Neuroscience

•Distinct from AI

•


Thinking humanly: Some References

– Daniel C. Dennet. Consciousness explained.– M. Posner (edt.) Foundations of cognitive science– Francisco J. Varela et al. The Embodied Mind– J.-P. Dupuy. The mechanization of the mind


Thinking rationally

“Laws of Thought”

“Can machines think rationally”

Several Greek schools developed various forms of logic: notation and rules of derivation for thoughts; may or may not have proceeded to the idea of mechanization


Aristotle: what are correct arguments/thought processes?

Mathematics and Philosophy to Modern AI

Problems: 1. Not all intelligent behavior is mediated by logical deliberation2. What is the purpose of thinking? What thoughts should I have?

A reference; Ivan Bratko, Prolog programming for artificial intelligence.

Thinking rationally


““Can machines behave like Humans?”Can machines behave like Humans?”

“Why and How” is not importantDo what ever you can

Acting humanly


Acting humanly: Turing Test• Turing (1950) "Computing machinery and intelligence"• Operational test for intelligent behavior: the Imitation Game

• Predicted that by 2000, a machine might have a 30% chance of fooling a lay person for 5 minutes

• Anticipated all major arguments against AI in following 50 years• Suggested major components of AI: knowledge, reasoning, language

understanding, learning


Objections :- Turning Test

Most AI Programs Are Not Flexible In Nature

May Not Be Able to Answer Emotional QuestionsEmotional Questions


• The Turing Test was the first attempt at resolving the question of machine

intelligence. • It was a behavioral test, judging intelligence based not on inner processes, or

faithfulness to neuronal structure, but purely on a computer's ability to verbally communicate.

• This approach elicited numerous objections: – Why should behaviour be the final test on intelligence– How can behavior suffice if the internal mechanisms controlling it are

nothing like a human being's? – How can a conversation capture all of human intelligence?

• These questions essentially reduced themselves to the question of whether one could pass the Turing Test, that is, produce passable conversational speech, while still possessing no 'real' intelligence. This argument has been stated in numerous ways, but perhaps none more eloquent than

John Searle's Chinese Room metaphor.http://psych.utoronto.ca/%7Ereingold/courses/ai/

Chinese Room


Searle Counter Example• Imagine a room, with a man trapped inside. The man speaks no

Chinese. Someone slips a piece of paper under the door with Chinese writing on it.

• Having puzzled over it for a moment, he notices that there is a book in the room titled "What to do if someone slides some Chinese writing under the door."

• The book, he finds, is actually an enormous set of instructions for producing new Chinese symbols based on what comes in. The rules instruct him on how to produce new Chinese symbols, based on the ones received. They are all if-then type statements describing a pattern in the text and the appropriate action or response.

• He follows these rules, using the piece of paper handed to him, and produces a new sheet, which he slides back under the door.

• The next day, another sheet comes in, he passes the completed sheet back out.

• Outside, the world is amazed that this room can actually understand Chinese, that the room is intelligent. Inside though, we know that the man understands no Chinese whatsoever!


ConclusionWhat Searle describes is a system that produces

intelligent, meaningful output, in the absence of true understanding. If you accept this counter-example, then the Turing Test is doomed. The Chinese Room would pass the Turing test, even though it lacks understanding and intelligence. Searle's argument has, naturally, produced its own share of furious debate, and several strong counter-arguments have been levelled at it.


References

1. http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/chineser.htm

2. http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/searle.html

3. http://consc.net/online2.html (best resource)

http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/chineser.htm

http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/chineser.htm

http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/searle.html

http://psych.utoronto.ca/%7Ereingold/courses/ai/cache/searle.html

http://consc.net/online2.html


Acting rationally

““Can machines behave rationally”Can machines behave rationally”

• Rational behavior: doing the right thing• The right thing: that which is expected to

maximize goal achievement, given the available information

• Doesn't necessarily involve thinking – e.g., blinking reflex – but thinking should be in the service of rational action


What is AI?

Views of AI fall into four categories:

Thinking humanly Thinking rationally

Acting humanly Acting rationally

Our Focus is "ACTING RATIONALLYACTING RATIONALLY"


Rational Agents

• An agent is an entity that perceives and acts• Every thing to be discussed should be taken in the

context of :RATIONAL AGENTS

• Abstractly, an agent is a function from percept histories to actions:

[f: P* A]• For a given class of environments/tasks, Rational

Agents sought best performance


Computational limitations make perfect rationality unachievable

Design best program for given machine resources

Limitations:Rational Agents

References

Michael Wooldridge. Reasoning about rational agents.


Definition: AI Systems

Artificial Systems that behave rationallyArtificial Systems that behave rationally

Or Or

limited rationality limited rationality


Other Aspects

Read it yourselfRead it yourself


Another Definition: AI?

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

Human Intelligence

CONTROVERSIAL ISSUE

(How to define Intelligence?)

More inclined towards acting and thinking humanly


IntelligenceReasoning + Learning

Intelligent Beings

Intelligent Systems

- Establishes Relationships- Perception and Comprehension- Generalization Ability

- Memory/Differentiation Chair vs Table Spoon vs Fork


Intelligence

Manifestation of intelligence is through Behavior


AI Though Groups

Strong Believers

Weak Believers


Weak AI?

Computation Consciousness

Brain has ingredients that are

Non - computational

Simulating consciousness is not possible

Computational + Non Computational

BRAIN


Strong AI ?

Consciousness - “is some complicated computation”

Brains Are Computers of MEAT?

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

achieved”achieved”


Strong and Weak AI

1. http://www.ecs.soton.ac.uk/~harnad/Papers/Py104/searle.comp.html

http://www.ecs.soton.ac.uk/~harnad/Papers/Py104/searle.comp.html

http://www.ecs.soton.ac.uk/~harnad/Papers/Py104/searle.comp.html


Scope of AI Based Techniques

Main focus Problems that do not have algorithmic solutions, or are very complex

Vague, uncertain and poor-defined systems

Systems with decision - making problems

(Examples?)


Example Tasks

Game Playing Rules are well defined algorithmic solutions are very complex Formalization is easy

Automated Reasoning Theorem proving Formal logic/ knowledge representation.

Expert SystemsMimic experts such as doctors

Coding

Knowledge Diagnostic

Experts

Experts


Natural Language Processing

Computer learn human languages Machine Translation Speech Synthesis

Planning And Robotics Artificial Pets. Efforts to make “machines”

- Responsive

- Flexible

e.g., Path Planning

Human Machine


Summary: AI?

• Innovative Extension of Philosophy:– Understand and BUILD intelligent entities

• Formal Origin after WWII

• Highly interdisciplinary

• Variety of subfields– This course will discuss some of them


AI prehistory

• Philosophy Logic, methods of reasoning, mind as physical system foundations of learning, language,

rationality• Mathematics Formal representation and proof algorithms,

computation, (un)decidability, (in)tractability,probability

• Economics Utility, decision theory • Neuroscience Physical substrate for mental activity• Psychology Phenomena of perception and motor control,

experimental techniques• Computer Building fast computers

engineering• Control theory Design systems that maximize an objective

function over time • Linguistics Knowledge representation, grammar


History of AI

• 1943 McCulloch & Pitts: Boolean circuit model of brain• 1950 Turing's "Computing Machinery and Intelligence"• 1956 Dartmouth meeting: "Artificial Intelligence" adopted• 1952—69 Look, Ma, no hands! • 1950s Early AI programs, including Samuel's checkers

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

• 1965 Robinson's complete algorithm for logical reasoning• 1966—73 AI discovers computational complexity

Neural network research almost disappears• 1969—79 Early development of knowledge-based systems• 1980-- AI becomes an industry • 1986-- Neural networks return to popularity• 1987-- AI becomes a science • 1995-- The emergence of intelligent agents


State of the art AI

• Deep Blue defeated the reigning world chess champion Garry Kasparov in 1997

• Proved a mathematical conjecture (Robbins conjecture) unsolved for decades

• No hands across America (driving autonomously 98% of the time from Pittsburgh to San Diego)

• During the 1991 Gulf War, US forces deployed an AI logistics planning and scheduling program that involved up to 50,000 vehicles, cargo, and people

• NASA's on-board autonomous planning program controlled the scheduling of operations for a spacecraft

• Proverb solves crossword puzzles better than most humans


First Reading Assignment(Write a Two Page Summary on What you think AI is)

Submission: Email the article to Instructor /TA by Friday 5:00 pm (or in folder submission_1 in Cs 531AI)

1. Luger’s

Chapter One: Introduction

Other References:

Alexander Igor’s Impossible minds

(Help Material Available in the Library)


Topics Covered Today

• Luger (Some of the discussion is from Stuart and Norvig)

– Part I– Chapter 1– Articles 1.1 to 1.4

• Practice:– Attempt Exercise Questions– Especially: Qs 1 to 7, 10 to 12

cs 531: dr m m awais (lums) cs 531: ai cs 331: introduction to ai dr mian muhammad awais room 416...

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