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CS 531/331: Introduction to AI Mian Muhammad Awais Room 416 awais@lums. edu. pk CS CS 531/331: Introduction to AI Mian Muhammad Awais Room 416 [email protected] edu. pk CS 331: Dr M M Awais (LUMS)

Course Description Course home page: suraj/lums. edu. pk/~cs 331 a 05 Contacts: lecture notes, Course Description Course home page: suraj/lums. edu. pk/~cs 331 a 05 Contacts: 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 TA Support/Office Hours • Natasha Qureshi (TA) [email protected] 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 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 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 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) Questions CS 331: Dr M M Awais (LUMS)

AI Dimensions 1) Modeling: Thought process/reasoning vs. behavior/action 2) Evaluation: Success according to human 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 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)

Acting humanly: Meaning Acting humanly: Meaning "Can machines behave like Humans? " CS 331: Dr M M Awais (LUMS)

Acting humanly: Turing Test • Turing (1950) 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) CS 331: Dr M M Awais (LUMS)

Objections : - Turning Test Most AI Programs Are Not Flexible In Nature May 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 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 • 1960 s Thinking humanly: cognitive modeling • 1960 s "cognitive revolution": information-processing psychology • Validation Requires • Predicting and testing behavior of human subjects (top-down) • Direct identification from neurological data -up) • Cognitive Science and Cognitive Neuroscience • Distinct from AI CS 331: Dr M M Awais (LUMS) (bottom

Thinking humanly: Some References – – Daniel C. Dennet. Consciousness explained. M. Posner (edt. 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 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)

Thinking rationally Aristotle: what are correct arguments/thought processes? Mathematics and Philosophy to Modern AI Thinking rationally Aristotle: what are correct arguments/thought processes? Mathematics and Philosophy to Modern AI Problems: 1. Not all intelligent behavior is mediated by logical deliberation 2. What is the purpose of thinking? What thoughts should I have? A reference; ¨ Ivan Bratko, Prolog programming for artificial intelligence. CS 331: Dr M M Awais (LUMS)

Acting rationally “Can machines behave rationally” • Rational behavior: doing the right thing • 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 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)

Limitations: Rational Agents Computational limitations make perfect rationality unachievable References (this leads to) Michael Limitations: Rational Agents Computational limitations make perfect rationality unachievable References (this leads to) Michael Wooldridge. Reasoning about rational agents. Design best program for given machine resources CS 331: Dr M M Awais (LUMS)

Definition: AI Systems Artificial Systems that behave rationally CS 331: Dr M M Awais 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 Another Definition: AI? Computer based solution of complex problems through the application of processes that are analogous to the Human Intelligence More inclined towards acting and thinking humanly CONTROVERSIAL ISSUE (How to define Intelligence) CS 331: Dr M M Awais (LUMS)

Intelligence Reasoning + - Establishes Relationships - Perception and Comprehension - Generalization Ability Learning Intelligence Reasoning + - Establishes Relationships - Perception and Comprehension - Generalization Ability Learning - Memory/Differentiation Chair vs Table Spoon vs Fork Intelligent Beings Intelligent Systems CS 331: Dr M M Awais (LUMS)

AI Though Groups Strong Believers Weak Believers 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 Ñ Non - computational Ñ Weak AI? Computation Consciousness Brain has ingredients that are Ñ Non - computational Ñ Simulating consciousness is not possible Computational + Non Computational BRAIN CS 331: Dr M M Awais (LUMS)

Strong AI ? Consciousness - “is some complicated computation” “Computers can achieve or even Strong AI ? Consciousness - “is some complicated computation” “Computers can achieve or even exceed all Human Capacities once high computational speeds are achieved” Brains Are Computers of MEAT? CS 331: Dr M M Awais (LUMS)

Scope of AI Based Techniques Main focus Problems that do not have algorithmic solutions, Scope of AI Based Techniques Main focus Problems that do not have algorithmic solutions, or are very complex Vague, uncertain and poordefined systems Systems with decision - making problems (Examples? ) CS 331: Dr M M Awais (LUMS)

Example Tasks Game Playing Ñ Ñ Ñ Rules are well defined algorithmic solutions are Example Tasks Game Playing Ñ Ñ Ñ Rules are well defined algorithmic solutions are very complex Formalization is easy Automated Reasoning Ñ Ñ Theorem proving Formal logic/ knowledge representation. Diagnostic Knowledge Expert Systems Mimic experts such as doctors Experts CS 331: Dr M M Awais (LUMS) Coding

Natural Language Processing Ñ Ñ Ñ Computer learn human languages Machine Translation Speech Synthesis Natural Language Processing Ñ Ñ Ñ Computer learn human languages Machine Translation Speech Synthesis Planning And Robotics Ñ Ñ Artificial Pets. Efforts to make “machines” - Responsive - Flexible e. g. , Path Planning CS 331: Dr M M Awais (LUMS) Human Machine

Summary: AI? • Innovative Extension of Philosophy: – Understand BUILD intelligent entities • Formal Summary: AI? • Innovative Extension of Philosophy: – Understand 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 • Mathematics • • • Economics Neuroscience Psychology • • AI prehistory • Philosophy • Mathematics • • • Economics Neuroscience Psychology • • Computer engineering Control theory • Linguistics Logic, methods of reasoning, mind as physical system foundations of learning, language, rationality Formal representation and proof algorithms, computation, (un)decidability, (in)tractability, probability Utility, decision theory Physical substrate for mental activity Phenomena of perception and motor control, experimental techniques Building fast computers Design systems that maximize an objective function over time Knowledge representation, grammar CS 331: Dr M M Awais (LUMS)

History of AI • • • 1943 1950 1956 1952— 69 1950 s • History of AI • • • 1943 1950 1956 1952— 69 1950 s • • 1965 1966— 73 • • • 1969— 79 1980 -1986 -1987 -1995 -- Mc. Culloch & Pitts: Boolean circuit model of brain Turing's "Computing Machinery and Intelligence" Dartmouth meeting: "Artificial Intelligence" adopted Look, Ma, no hands! Early AI programs, including Samuel's checkers program, Newell & Simon's Logic Theorist, Gelernter's Geometry Engine Robinson's complete algorithm for logical reasoning AI discovers computational complexity Neural network research almost disappears Early development of knowledge-based systems AI becomes an industry Neural networks return to popularity AI becomes a science 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 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: 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) 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 331: Dr M M Awais (LUMS)