COSC 6368 and “What is AI?”

1. COSC 6368 and “What is AI?” • Introduction to AI (today, and TH) • What is AI? • Sub-fields of AI • Problems investigated by AI research • Course Organization • Prerequisites, Schedules, Grading, General Advice

2. Definitions of AI • “AI centers on the simulation of intelligence using computers” • “AI develops programming paradigms, languages, tools, and environments for application areas for which conventional programming fails” • Symbolic programming (LISP) • Functional programming • Heuristic Programming • Logical Programming (PROLOG) • Rule-based Programming (Expert system shells) • Soft Computing (Belief network tools, fuzzy logic tool boxes,…) • Object-oriented programming (Smalltalk)

3. More Definitions of AI • Rich/Knight: ”AI is the study of of how to make computers do things which, at the moment, people do better” • Winston: “AI is the study of computations that make it possible to perceive, reason, and act. • Turing Test: If an artificial intelligent system is not distinguishable from a human being, it is definitely intelligent.

4. Physical Symbol System Hypothesis • “What the brain does can be thought of at some level as a kind of computation” • Physical Symbol System Hypothesis (PSSH): A physical symbol system has the sufficient and necessary means for general, intelligent actions. Remarks PSSH: • Subjected to empirical validation • If false  AI is quite limited • Important for psychology and philosophy

5. Questions/Thoughts about AI • What are the limitations of AI? Can computers only do what they are told? Can computers be creative? Can computers think? What problems cannot be solved by computers today? • Computers show promise to control the current waste of energy and other natural resources. • Computer can work in environment that are unsuitable for human beings. • If computers control everything --- who controls the computers? • If computers are intelligent what civil rights should be given to computers? • If computers can perform most of our work; what should the human beings do? • Only those things that can be represented in computers are important. • It is fun to play with computers.

6. Topics Covered in COSC 6368 • More general topics: • heuristic search and search algorithm in general • logical reasoning (FOPL as a language) • making sense out of data • AI-specific Topics: • resolution / theorem proving • reasoning in uncertain environments and belief networks • machine learning and data mining • brief coverage of ontologies, evolutionary computing, AI and the web, knowledge-based systems and philosophical aspects of AI • Exposure to AI tools (belief networks, decision trees,…)

7. 2004 Organization COSC 6368 • Introduction AI and Course Information (1-2 classes) • Heuristic Search (3-4 classes) • Evolutionary Computing (1-2 classes) • FOPL, Logical Reasoning, PROLOG, and Resolution (4 classes) • Machine Learning and Data Mining (5 classes) • Ontologies, the Semantic Web and Intelligent Information Retrieval (2 classes) • Belief Networks and Reasoning in Uncertain Environments (3 classes) • Knowledge-based Systems and Expert Systems (1 class) • General Aspects of AI (1 class) • Other Activities: Midterm exam (1 class), review (1 class), group project (1 class), homework/project-related discussions(1 class), paper walk-through (1 class).

8. AI in General and What Is not Covered in COSC 6368 • Robotics is a quite important sub-field of AI, but very few teach it in the graduate AI class. • Planning and natural language understanding probably will not be covered. • Intelligent Agents and AI for the Internet could/should possibly be covered in a little more depth. • Artificial intelligence programming is not covered. • Techniques employed in systems that automate decision making in uncertain environments deserves more attention (e.g. Fuzzy Logic, rule-based programming languages and expert system shells, fuzzy controllers,

9. Positive Forces for AI • Knowledge Discovery in Data and Data Mining (KDD) • Intelligent Agents for WWW • Robotics (Robot Soccer, Intelligent Driving, Robot Waiters, industrial robots, rovers, toy robots…) • Creating of Knowledge Bases and Sharing of Knowledge (especially for Science and Engineering) • Computer Chess and Computer Games --- AI for Entertainment

10. UHData Mining and Machine Learning GroupLead by: Ricardo Vilalta and Christoph F. Eick Topics investigated: • Clustering for Classification • Decision Trees / Nearest Neighbor Classifiers / Support Vector Machines • Theoretical Aspects of Classifiers and Classification Tasks • Supervised Clustering • Summary Generation • Distance Function Learning • Using Reinforcement Learning for Data Mining • Making Sense of Data • Database Clustering • Feature Construction • Meta-Learning • Application of AI to Physics and Astronomy

11. Course Elements • 22 Lectures • 2 Exams (one Midterm, one Final Exam) • 4 Graded Assignments (review questions, exam style paper and pencil problems, a few more challenging problems that might require programming; problems that require using AI tools) • Un-graded Homeworks (solutions will usually discussed in class) • 1 Paper Walk-Throughs • Discussion of assignments and homeworks

12. Teaching 6368 in 2004 ---what changed since 2002? • The second edition of the Russel/Norvig book came out in November 2002 (update of teaching material; better transparencies) • Some 2002 teaching material will be replaced by other teaching material • A lot more AI technique animations are available now --- I will try to use some of those for teaching purposes • There will be some changes what will be covered in 2004 (see webpage)

13. AI Programming Knowledge Representation Knowledge-based and Expert Systems AI Planning Coping with Vague, Incomplete and Uncertain Knowledge Searching Intelligently Logical Reasoning & Theorem Proving Communicating, Perceiving and Acting Intelligent Agents & Distributed AI Learning & Knowledge Discovery

14. Knowledge Representation Problem: Can the above chess board be coverer by 31 domino pieces that cover 2 fields? AI’s contribution: object-oriented and frame-based systems, ontology languages, logical knowledge representation frameworks, belief networks

15. Natural Language Understanding • I saw the Golden Gate Bridge flying to San Francisco. • I ate dinner with a friend. I ate dinner with a fork. • John went to a restaurant. He ordered a steak. After an hour John left happily. • I went to three dentists this morning.

16. Planning Objective: Construct a sequence of actions that will achieve a goal. Example: John want to buy a house

17. Heuristic Search • Heuristo (greek): I find • Copes with problems for which it is not feasible to look at all solutions • Heuristics: rules a thumb (help you to explore the more promising solutions first), based on experience, frequently fuzzy • Main ideas of heuristics: search space reduction, ordering solutions intelligently, simplifications of computations Example problems: puzzles, traveling salesman problem, …

18. Figure

19. Evolutionary Computing • Evolutionary algorithms are global search techniques. • They are built on Darwin’s theory of evolution by natural selection. • Numerous potential solutions are encoded in structures, called chromosomes. • During each iteration, the EA evaluates solutions adn generates offspring based on the fitness of each solution in the task. • Substructures, or genes, of the solutions are then modified through genetic operators such as mutation or recombination. • The idea: structures that led to good solutions in previous evaluations can be mutated or combined to form even better solutions.

20. Logical Reasoning • Learn how to represents natural language statements in logic (AI as language) • Automated theorem proving

21. Soft Computing Conventional Programming: • Relies on two-valued logic • Mostly uses a symbolic (non-numerical knowledge representation framework) Soft Computing (e.g. Fuzzy Logic, Belief Networks,..): • Tolerance for uncertainty and imprecision • Uses weights, probabilities, possibilities • Strongly relies on numeric approximation and interpolation Remark: There seem to be two worlds in computer science; one views the world as consisting of numbers; the other views the world as consisting of symbols.

22. Different Forms of Learning • Learning agent receives feedback with respect to its actions (e.g. using a teacher) • Supervised Learning: feedback is received with respect to all possible actions of the agent • Reinforcement Learning: feedback is only received with respect to the taken action of the agent • Unsupervised Learning: Learning without feedback

23. Training Data Classifier (Model) Machine Learning Classification- Model Construction (1) Classification Algorithms IF rank = ‘professor’ OR years > 6 THEN tenured = ‘yes’

24. Classifier Testing Data Unseen Data Classification Process (2): Use the Model in Prediction (Jeff, Professor, 4) Tenured?

25. Knowledge Discovery in Data [and Data Mining] (KDD) • Definition := “KDD is the non-trivial process of identifying valid, novel, potentially useful, and ultimately understandable patterns in data” (Fayyad) Let us find something interesting!

26. 2004 Organization COSC 6368 • Introduction AI and Course Information (1-2 classes) • Heuristic Search (3-4 classes) • Evolutionary Computing (1-2 classes) • FOPL, Logical Reasoning, PROLOG, and Resolution (4 classes) • Machine Learning and Data Mining (5 classes) • Ontologies, the Semantic Web and Intelligent Information Retrieval (2 classes) • Belief Networks and Reasoning in Uncertain Environments (3 classes) • Knowledge-based Systems and Expert Systems (1 class) • General Aspects of AI (1 class) • Other Activities: Midterm exam (1 class), review (1 class), group project (1 class), homework/project-related discussions(1 class), paper walk-through (1 class).