Bayesian networks (1)
Lirong Xia
Spring 2017
Project 2
alpha-beta
v>beta
v<alpha
different from book/slides
depth
each depth means a full round of Pacman-ghost
not Pacman or ghost
may have multiple ghosts
My OH moved to Thursday at 3 pm
2
Random
Informed search
Lirong Xia
Spring, 2017
Last class
Search problems
state space graph: modeling the problem
search tree: scratch paper for solving the problem
Uninformed search
BFS
DFS
2
Todays schedule
More on uninformed search
iterative deepening: B
Probability
Lirong Xia
Spring 2017
Todays schedule
Probability
probability space
events
independence
conditional probability
Bayes rule
Random variables
Probabilistic inference
2
Probability space
A sample space
states of the world,
or equival
Minimax strategies, alpha beta
pruning
Lirong Xia
Friday, February 3, 2017
Reminder
Project 1 due tonight
Makes sure you DO NOT SEE ERROR:
Summation of parsed points does not match
Project 2 due in two weeks
2
How to find good heuristics?
No really mecha
Uninformed search
Lirong Xia
Spring, 2017
Todays schedule
Rational agents
Search problems
State space graph: modeling the problem
Search trees: scratch paper for solution
Uninformed search
Depth first search (DFS) algorithm
Breadth first search (BFS)
CSP, linear programming, games
Lirong Xia
Spring, 2017
Project 1
Admissibility must be satisfied
Otherwise your A* can be wrong on some
instances
It doesnt mean that your A* is always wrong-you
might be lucky on one test
Good heuristics
Consistent
Eas
Bayesian networks (2)
Lirong Xia
Spring, 2017
Last class
Bayesian networks
compact, graphical representation of a joint
probability distribution
conditional independence
2
Bayesian network
Definition of Bayesian network (Bayes
net or BN)
A set of nod
Expectimax
Lirong Xia
Spring 2017
Project 2
MAX player: Pacman
Question 1-3: Multiple MIN players: ghosts
Extend classical minimax search and alpha-beta
pruning to the case of multiple MIN players
Important: A single search ply is considered to be
one
Constraint satisfaction problems
Lirong Xia
Spring, 2017
Project 1
You can use Windows
Read the instruction carefully, make sure you
understand the goal
search for YOUR CODE HERE
Ask and answer questions on Piazza
we may give bonus score to insightfu
Introduction to Artificial
Intelligence
Lirong Xia
Tuesday, January 17, 2017
Basic information about course
TuFri 12:00-1:50pm, DARRIN 308
Text: Artificial Intelligence: A Modern Approach
Course website: google Lirong Xia and follow the
link
Instructo
Time and Coordination in
Distributed Systems
INF 5040 autumn 2015
lecturer: Roman Vitenberg
INF5040, Roman Vitenberg
1
We live in an asynchronous
world
Each entity or process has its own pace
Computers, OS processes, mobile devices, vehicles,
satellites
A Tree-Based Algorithm for Distributed
Mutual Exclusion
KERRY RAYMOND
University of Queensland
We present an algorithm for distributed mutual exclusion in a computer network of N nodes that
communicate by messages rather than shared memory. The algorithm
A Modular Approach to
Fault-Tolerant Broadcasts
and Related Problems
Sam Toueg y
Department of Computer Science
Cornell University
Ithaca, New York 14853, USA
Vassos Hadzilacos
Department of Computer Science
University of Toronto
Toronto, Ontario, Canada
The Information Structure of Distributed
Mutual Exclusion Algorithms
BEVERLY A. SANDERS
University of Maryland
The concept of an information structure is introduced as a unifying principle behind several of the
numerous algorithms that have been proposed
1. Introduction
Operating Systems
R. Stockton Gaines
Editor
An Optimal Algorithm
for Mutual Exclusion
in Computer Networks
Glenn Ricart
National Institutes of Health
Ashok K. Agrawala
University of Maryland
An algorithm is proposed that creates mutual exc
Efficient Solutions
to
the Replicated Log and Dictionary Problems*
G e n e T . J . W u u a n d A r t h u r J. B e r n s t e i n
Depurtmemnt
of C o m p u t e r S c i e n c e
S t a t e U n i v e r s i t y of N e w Y o r k a t S t o n y B r o o k
L o n g I s
Consensus Protocol: The Consensus problem requires that all correct processes propose a
value, and then reach an agreement on some value.
The protocol must ensure:
agreement: Every node decides the same value
validity: Only decide on proposed values
te
Why Do We Care About Time
in a Distributed System?
Physical Clocks
may need to know the time of day some event happened on a
need for time in distributed systems
physical clocks and their problems
synchronizing physical clocks
u
u
u
u
coordinated univ