Week 1 - Subbarao Kambhampati

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Transcript Week 1 - Subbarao Kambhampati

Open only for Humans; Droids and Robots should go for CSE 462 next door ;-)
General Information
• Instructor: Subbarao Kambhampati (Rao)
– Office hours: after class, T/Th: 3-4pm
• TA: Lei Tang
– Office hours: TBD (will be twice weekly)
– Additional help (on request/one-on-one) by J. Benton;
G. Wolfe; Will Cushing, Sungwook Yoon
• Send mail to [email protected] …
• Course Homepage:
http://rakaposhi.eas.asu.edu/cse471
Grading etc.
– Projects/Homeworks/Participation (~55%)
• Projects
– Approximately 4
» First project already up! Due in 2 weeks
– Expected background
» Competence in Lisp programming
» Why lisp? (Because!)
• Homeoworks
– Homeworks will be assigned piecemeal.. (Socket system)
• Participation
– Attendance to and attentiveness in classes is mandatory
– Do ask questions
– Midterm & final (~45%)
Grade Anxiety
• All letter grades will be awarded
– A+,A,B+,B,B-,C+,C,D etc.
• No pre-set grade thresholds
• CSE471 and CSE598 students will have the same
assignments/tests etc. During letter grade
assignment however, they will be compared to
their own group.
– The class is almost evenly split between CSE471 and
CSE598 (grad) students
Honor Code
• Unless explicitly stated otherwise, all
assignments are:
– Strictly individual effort
– You are forbidden from trawling the web for
answers/code etc
• Any infraction will be dealt with in severest
terms allowed.
Life with a homepage..
• I will not be giving any handouts
– All class related material will be accessible
from the web-page
• Home works may be specified incrementally
– (one problem at a time)
– The slides used in the lecture will be available
on the class page
• I reserve the right to modify slides right up to the
time of the class
• When printing slides avoid printing the hidden
slides
1946: ENIAC heralds the dawn of Computing
1950: Turing asks the question….
I propose to consider the question:
“Can machines think?”
--Alan Turing, 1950
1956: A new field is born


We propose that a 2 month, 10
man study of artificial
intelligence be carried out
during the summer of 1956 at
Dartmouth College in Hanover,
New Hampshire.
- Dartmouth AI Project
Proposal; J. McCarthy et al.;
Aug. 31, 1955.
1996: EQP proves that
Robbin’s Algebras are all boolean
----- EQP 0.9, June 1996 ----The job began on eyas09.mcs.anl.gov, Wed Oct 2 12:25:37 1996
UNIT CONFLICT from 17666 and 2 at 678232.20 seconds.
---------------- PROOF ---------------2 (wt=7) [] -(n(x + y) = n(x)).
3 (wt=13) [] n(n(n(x) + y) + n(x + y)) = y.
5 (wt=18) [para(3,3)] n(n(n(x + y) + n(x) + y) + y) = n(x + y).
6 (wt=19) [para(3,3)] n(n(n(n(x) + y) + x + y) + y) = n(n(x) + y).
…….
17666 (wt=33) [para(24,16426),demod([17547])] n(n(n(x) + x) ….
[An Argonne lab program] has come up with a major mathematical
proof that would have been called creative if a human had thought of it.
-New York Times, December, 1996
1997: HAL 9000 becomes operational
in fictional Urbana, Illinois
…by now, every intelligent person knew that
H-A-L is derived from Heuristic ALgorithmic
-Dr. Chandra, 2010: Odyssey Two
1997: Deep Blue ends Human
Supremacy in Chess
vs.
I could feel human-level intelligence across the room
-Gary Kasparov, World Chess Champion (human)
In a few years, even a single victory
in a long series of games would be the triumph of human genius.
1999: Remote Agent takes
Deep Space 1 on a galactic ride
Goals
Scripts
Scripted
Executive
ESL
Mission-level
actions &
resources
Generative
Planner &
Scheduler
Generative
Mode Identification
& Recovery
component models
Monitors
Real-time Execution
Adaptive Control
Hardware
For two days in May, 1999, an AI Program called Remote Agent
autonomously ran Deep Space 1 (some 60,000,000 miles from earth)
2002: Computers start passing
Advanced Placement Tests
… a project funded by
(Microsoft Co-founder) Paul
Allen attempts to design a
“Digital Aristotle”.
Its first results involve
programs that can pass High
School Advanced Placement
Exam in Chemistry…
2005: Cars Drive Themselves

Stanley and three
other cars drive
themselves over
a 132 mile
mountain road
2005: Robots play soccer
(without headbutting!)

2005 Robot Soccer:
Humanoid league
2006: AI Celebrates its Golden Jubilee…
2006: AI Celebrates its Golden Jubilee…
…and invites you along..
Welcome!
To
CSE471/598
th
50 Anniversary Edition
(tons of bonus material)
Course Overview
•
•
What is AI
– Intelligent Agents
Search (Problem Solving Agents)
– Single agent search [Project 1]
• Markov Decision Processes
•
•
•
•
• Constraint Satisfaction Problems
– Adversarial (multi-agent) search
Logical Reasoning [Project 2]
Reasoning with uncertainity
Planning [Project 3]
Learning [Project 4]
What if we are writing intelligent
agents that interact with humans?
The COG project
Mechanical flight became possible only when people decided to stop
emulating birds…
What AI can do is as important as
what it can’t yet do..
• Captcha project
Arms race to defeat Captchas…
(using unwitting masses)
• Start opening an email account at
Yahoo..
• Clip the captcha test
• Show it to a human trying to get into
another site
– Usually a site that has pretty pictures of
the persons of apposite* sex
• Transfer their answer to the Yahoo
Note: Apposite—not opposite. This course is nothing if not open minded 
Do we want a machine that beats humans in chess or a machine that thinks like humans
while beating humans in chess?
DeepBlue supposedly DOESN’T think like humans..
It can be argued that all the faculties needed to pass turing test are also needed to act rationally
to improve success ratio…
Playing an (entertaining) game of Soccer
Solving NYT crossword puzzles at close to expert level
Navigating in deep space
Learning patterns in databases (datamining…)
Supporting supply-chain management decisions at fortune-500 companies
Bringing “Semantics” to the web
Playing an (entertaining) game of Soccer
Solving NYT crossword puzzles at close to expert level
Navigating in deep space
Learning patterns in databases (datamining…)
Supporting supply-chain management decisions at fortune-500 companies
Bringing “Semantics” to the web
Pluto in mourning..
8/24
Grigory Perelman
Architectures for Intelligent Agents
Wherein we discuss why do we need representation, reasoning and learning
TA office hours etc.
• TA: Lei Tang
• Office hours:
– Regular: M/W 3:30—4:30 BYENG 214
• (Exception Tomorrow: Friday: 10-12; BY561AC)
Survey Sheet Summary
• Reasons for taking course:
– Most said “Sounded interesting” or “will be of use in our research”
(examples include AI&biology; AI&games)
• Topics suggested
–
–
–
–
Neural networks (perennial favorite  )
Machine learning
Multi-agent (sytems, learning)
Perception/Robotics
• Recitation session
– 19 said they would be very interested
– 21 said they would have some interest
– (out of a total of 50)
• Other questions?
Course Overview
•
•
What is AI
– Intelligent Agents
Search (Problem Solving Agents)
– Single agent search [Project 1]
• Markov Decision Processes
•
•
•
•
• Constraint Satisfaction Problems
– Adversarial (multi-agent) search
Logical Reasoning [Project 2]
Reasoning with uncertainity
Planning [Project 3]
Learning [Project 4]
We will explain the role of these topics
in the context of designing intelligent
agents
Environment
What action next?
A: A Unified Brand-name-Free Introduction to Planning
Subbarao Kambhampati
Partial contents of sources as found by Get
Get,Post,Buy,..
Cheapest price on specific goods
Internet, congestion, traffic, multiple sources
and prior knowledge
Rational != Intentionally avoiding sensing
“history” = {s0,s1,s2……sn….}
Performance = f(history)
Expected Performance= E(f(history))
(Static vs. Dynamic)
Environment
(perfect vs.
Imperfect)
(Full vs.
Partial satisfaction)
Goals
(Observable vs.
Partially Observable)
(Instantaneous vs.
Durative)
(Deterministic vs.
Stochastic)
What action next?
A: A Unified Brand-name-Free Introduction to Planning
Subbarao Kambhampati
#Agents
Yes
Yes
No
Yes
Yes
#1
No
No
No
No
No
>1
Accessible: The agent can “sense” its environment
best: Fully accessible worst: inaccessible typical: Partially accessible
Deterministic: The actions have predictable effects
best: deterministic worst: non-deterministic typical: Stochastic
Static: The world evolves only because of agents’ actions
best: static worst: dynamic typical: quasi-static
Episodic: The performance of the agent is determined episodically
best: episodic worst: non-episodic
Discrete: The environment evolves through a discrete set of states
best: discrete worst: continuous typical: hybrid
Agents: # of agents in the environment; are they competing or cooperating?
Booo hooo 
(Model-based reflex agents)
This one already assumes that the “sensorsfeatures” mapping has been done!
(aka Model-based Reflex Agents)
EXPLICIT MODELS OF THE ENVIRONMENT
--Blackbox models (child function)
--Logical models
--Probabilistic models
Representation & Reasoning
It is not always obvious what action to do now given a set of goals
You woke up in the morning. You want to attend a class. What should your action be?
 Search (Find a path from the current state to goal state; execute the first op)
Planning (does the same for logical—non-blackbox state models)
..certain inalienable rights—life, liberty and pursuit of
?Money
?Daytime TV
?Happiness (utility)
--Decision Theoretic Planning
--Sequential Decision Problems
Discounting
• The decision-theoretic agent often needs to assess the
utility of sequences of states (also called behaviors).
– One technical problem is “How do keep the utility of an infinite
sequence finite?
– A closely related real problem is how do we combine the utility of
a future state with that of a current state (how does 15$ tomorrow
compare with 5000$ when you retire?)
– The way both are handled is to have a discount factor r (0<r<1)
and multiply the utility of nth state by rn
• r0 U(so)+ r1 U(s1)+…….+ rn U(sn)+
• Guaranteed to converge since power series converge for 0<r<n
– r is set by the individual agents based on how they think future
rewards stack up to the current ones
• An agent that expects to live longer may consider a larger r than one
that expects to live shorter…
Representation Mechanisms:
Logic (propositional; first order)
Probabilistic logic
Learning
the models
How the course topics stack up…
Search
Blind, Informed
Planning
Inference
Logical resolution
Bayesian inference
Learning
Dimensions:
What can be learned?
--Any of the boxes representing
the agent’s knowledge
--action description, effect probabilities,
causal relations in the world (and the
probabilities of causation), utility models
(sort of through credit assignment), sensor
data interpretation models
What feedback is available?
--Supervised, unsupervised,
“reinforcement” learning
--Credit assignment problem
What prior knowledge is available?
-- “Tabularasa” (agent’s head is a blank
slate) or pre-existing knowledge