Post on 04-Jan-2016
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CS 331: Dr M M Awais (LUMS)
CS 531/331: Introduction to AI
Mian Muhammad Awais
Room 416
awais@lums.edu.pk
CS 331: Dr M M Awais (LUMS)
Course DescriptionCourse home page: suraj/lums.edu.pk/~cs331a05Contacts: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%)Lab/Assignments/Project (15%), Midterm test (30%)Final exam (40%)
At least 2 Lab Assignments where attendance will be compulsory and will be taken. Midterm test (in class) and final exam (as per schedule)
CS 331: Dr M M Awais (LUMS)
TA Support/Office Hours
• Natasha Qureshi (TA)
natasha@lums.edu.pk
Office hours (see the website)
• Instructor Office Hours:
3 to 4 PM Every day except Friday
CS 331: Dr M M Awais (LUMS)
Course Outline
• 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
CS 331: Dr M M Awais (LUMS)
Book Chapters
• Book Chapters and articles will be announced as we go along
• Slides will be available at the website and the common’s folder
CS 331: Dr M M Awais (LUMS)
Informal Feedback Mechanism
• Every Two Weeks an anonymous questionnaire will be circulated to evaluate the course
• Your comments will be welcomed to improve the course
• We will also have course progress discussion after every two weeks
CS 331: Dr M M Awais (LUMS)
Questions
CS 331: Dr M M Awais (LUMS)
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: rationality.
CS 331: Dr M M Awais (LUMS)
What is AI?
Views of AI fall into four categories:
Thinking humanly Thinking rationally
Acting humanly Acting rationally
Our Focus is "ACTING RATIONALLY"
CS 331: Dr M M Awais (LUMS)
"Can machines behave like Humans?"
Acting humanly: Meaning
CS 331: Dr M M Awais (LUMS)
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
••
CS 331: Dr M M Awais (LUMS)
CS 331: Dr M M Awais (LUMS)
Objections :- Turning Test
Most AI Programs Are Not Flexible In Nature
May Not Be Able to Answer Emotional Questions
CS 331: Dr M M Awais (LUMS)
Thinking humanly
“Can machines think like humans”
• Requires scientific theories of internal activities of the brain
• Cognitive Modeling
CS 331: Dr M M Awais (LUMS)
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
•
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
Acting 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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
Computational limitations make perfect rationality unachievable
(this leads to)
Design best program for given machine resources
Limitations:Rational Agents
References
Michael Wooldridge. Reasoning about rational agents.
CS 331: Dr M M Awais (LUMS)
Definition: AI Systems
Artificial Systems that behave rationally
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
IntelligenceReasoning + Learning
Intelligent Beings
Intelligent Systems
- Establishes Relationships- Perception and Comprehension- Generalization Ability
- Memory/Differentiation Chair vs Table Spoon vs Fork
CS 331: Dr M M Awais (LUMS)
AI Though Groups
Strong Believers
Weak Believers
CS 331: 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 331: Dr M M Awais (LUMS)
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”
CS 331: Dr M M Awais (LUMS)
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?)
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
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
CS 331: Dr M M Awais (LUMS)
First Reading Assignment(Write a Two Page Summary on the Scope of AI)
Submission: Email the article to Instructor /TA by Friday 5:00 pm
1. Luger’s
Chapter One: Introduction
Other References:
Alexander Igor’s Impossible minds
(Help Material Available in the Library)
CS 331: Dr M M Awais (LUMS)
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