CS B551: ELEMENTS OF ARTIFICIAL INTELLIGENCEInstructor: Kris Hauserhttp://cs.indiana.edu/~hauserk

1

BASICS Class web site

http://cs.indiana.edu/classes/b551 Textbook

S. Russell and P. Norvig Artificial Intelligence: a Modern Approach 3rd edition

2nd edition can be used, but is not preferable

2

BASICS Instructor

Kris Hauser (hauserk@indiana.edu) AIs

Mark Wilson (mw54@indiana.edu)

3

OFFICE HOURS Kris Hauser

Tu 10-11,W 12-1 in Info E 257 Mark Wilson

M 1-2, Th 9-11 in TBA

4

AGENDA Intro to AI Overview of class policies

5

WHAT IS AI? AI is the reproduction of human reasoning

and intelligent behavior by computational methods

6

WHAT IS AI? AI is an attempt of reproduction of human

reasoning and intelligent behavior by computational methods

7

WHAT IS AI? Discipline that systematizes and automates

reasoning processes to create machines that:

8

Think like humans Think rationallyAct like humans Act rationally

The goal of AI is: to build machines that operate in the same way that humans thinkHow do humans think?Build machines according to theory, test how

behavior matches mind’s behaviorCognitive Science

Manipulation of symbolic knowledge How does hardware affect reasoning?

Discrete machines, analog minds9

Think like humans Think rationallyAct like humans Act rationally

The goal of AI is: to build machines that perform tasks that seem to require intelligence when performed by humans

Take a task at which people are better, e.g.: Prove a theorem Play chess Plan a surgical operation Diagnose a disease Navigate in a building

and build a computer system that does it automatically

But do we want to duplicate human imperfections?

10

Think like humans Think rationallyAct like humans Act rationally

The goal of AI is: to build machines that make the “best” decisions given current knowledge and resources

“Best” depending on some utility function Influences from economics, control theory

How do self-consciousness, hopes, fears, compulsions, etc. impact intelligence?

Where do utilities come from?11

Think like humans Think rationallyAct like humans Act rationally

WHAT IS INTELLIGENCE?“If there were machines which bore a resemblance to our bodies and imitated our actions as closely as possible for all practical purposes, we should still have two very certain means of recognizing that they were not real men. The first is that they could never use words, or put together signs, as we do in order to declare our thoughts to others… Secondly, even though some machines might do some things as well as we do them, or perhaps even better, they would inevitably fail in others, which would reveal that they are acting not from understanding, …”Discourse on the Method, by Descartes (1598-1650)

12

WHAT IS INTELLIGENCE? Turing Test (c. 1950)

13

14

AN APPLICATION OF THE TURING TEST CAPTCHA: Completely Automatic Public

Turing tests to tell Computers and Humans Apart

15

CHINESE ROOM (JOHN SEARLE)

16

CAN MACHINES ACT/THINK INTELLIGENTLY? Yes, if intelligence is narrowly defined as

information processingAI has made impressive achievements showing that tasks initially assumed to require intelligence can be automatedEach success of AI seems to push further the limits of what we consider “intelligence”

17

SOME ACHIEVEMENTS Computers have won over world

champions in several games, including Checkers, Othello, and Chess, but still do not do well in Go

AI techniques are used in many systems: formal calculus, video games, route planning, logistics planning, pharmaceutical drug design, medical diagnosis, hardware and software trouble-shooting, speech recognition, traffic monitoring, facial recognition, medical image analysis, part inspection, etc...

DARPA Grand Challenge: robotic car autonomously traversed 132 miles of desert

IBM’s Watson competes with Jeopardy champs

Some industries (automobile, electronics) are highly robotized, while other robots perform brain and heart surgery, are rolling on Mars, fly autonomously, …, but home robots still remain a thing of the future

18

18

CAN MACHINES ACT/THINK INTELLIGENTLY? Yes, if intelligence is narrowly defined as

information processingAI has made impressive achievements showing that tasks initially assumed to require intelligence can be automated

Maybe yes, maybe not, if intelligence cannot be separated from consciousness Is the machine experiencing thought? Strong vs. Weak AI

19

BIG OPEN QUESTIONS Is intelligent behavior just information

processing?(Physical symbol system hypothesis)

If so, can the human brain solve problems that are inherently intractable for computers? Will a general theory of intelligence emerge from neuroscience?

In a human being, where is the interface between “intelligence” and the rest of “human nature”Self-consciousness, emotions, compulsions

What is the role of the body?(Mind-body problem)

20

21

AI contributes to building an information processing model of human beings, just as Biochemistry contributes to building a model of human beings based on bio-molecular interactions

Both try to explain how a human being operates

Both also explore ways to avoid human imperfections (in Biochemistry, by engineering new proteins and drug molecules; in AI, by designing rational reasoning methods)

Both try to produce new useful technologies

Neither explains (yet?) the true meaning of being human

MAIN AREAS OF AI Knowledge representation

(including formal logic) Search, especially

heuristic search (puzzles, games)

Planning Reasoning under

uncertainty, including probabilistic reasoning

Learning Robotics and perception Natural language

processing22

Search

Knowledgerep.Planning

Reasoning

Learning

AgentRobotics

Perception

Naturallanguage ... Expert

Systems

Constraintsatisfaction

BITS OF HISTORY 1956: The name “Artificial Intelligence” is

coined 60’s: Search and games, formal logic and

theorem proving 70’s: Robotics, perception, knowledge

representation, expert systems 80’s: More expert systems, AI becomes an

industry 90’s: Rational agents, probabilistic reasoning,

machine learning 00’s: Systems integrating many AI methods,

machine learning, natural language processing, reasoning under uncertainty, robotics again

23

AI REFERENCES Conferences

IJCAI, ECAI, AAAI, NIPS Journals

AI, Comp. I, IEEE Trans. Pattern Anal. Mach. Intel., IEEE Int. Sys., JAIR

Societies AAAI, SIGART, AISB

AI Magazine (Editor: IU’s David Leake)

24

CAREERS IN AI ‘Pure’ AI

Academia, industry labs Applied AI

Almost any area of CS! NLP, vision, robotics Economics

Cognitive Science

25

SYLLABUS Introduction to AI

Philosophy, history, agent frameworks Search

Uninformed search, heuristic search, heuristics, game playing

Reasoning under uncertainty Probability, planning under uncertainty, Bayesian

networks, probabilistic inference, temporal sequences

Machine learning Neural nets, decision tree learning, support vector

machines, etc. Applications

Constraint satisfaction, motion planning, computer vision

26

27

B335

Robotics

I400

B552 B553

Knowledge representation and learning

B657

Computer Vision

Biologically-inspired computing

B659

I486

Q360B651

Natural Language Processing

E626

Game theory

Q570

Topics in AI

B551

S626 S675

B555 B556

B553

Algorithms for Optimization and Learning

CLASS POLICIES28

PREREQUISITES C211 I recommend:

Two semesters programming Basic knowledge of data structures Basic knowledge of algorithmic complexity

29

PROGRAMMING ASSIGNMENTS Projects will be written in Python Great for scripting

Peter Norvig, Director of Research at Google, and textbook author

Easy to learn 2 weeks for each assignment

30

GRADING 70% Homework

8 assignments - lowest score will be dropped 30% Final

31

HOMEWORK POLICY Due at end of class on due date

Typically Thursdays Extensions only granted in rare cases

Require advance notice except emergencies

32

33

FINAL PROJECT Encouraged if you are intending to do

research or coursework in AI, pursue higher degree Individual or small groups (up to 3)Counts as three homework assignments

ContentSoftware, new research, or technical reportMid-semester project proposalEnd-of-year report and in-class

presentation

ENROLLMENT Add/drop deadline

No penalty: Sept 2 Late drop/add: Oct 26

Waitlist deadline: Sept 3

34

TAKEAWAYS AI has many interpretations

Act vs. think, human-like vs. rational Concept has evolved

“Intelligence” has many interpretations Turing test Chinese room

AI success stories from each perspective

35

HOMEWORK Register Textbook Survey http://cs.indiana.edu/classes/b551 Readings:

R&N Ch. 1, 26 (introduction and historical perspectives)

R&N 3.1-3

36