Lec 5: April 11th, 2006EE512 - Graphical Models - J. BilmesPage 1 Jeff A. Bilmes University of...

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Transcript of Lec 5: April 11th, 2006EE512 - Graphical Models - J. BilmesPage 1 Jeff A. Bilmes University of...

Lec 5: April 11th, 2006 EE512 - Graphical Models - J. Bilmes Page 1

University of WashingtonDepartment of Electrical Engineering

EE512 Spring, 2006 Graphical Models

Jeff A. Bilmes <bilmes@ee.washington.edu>Jeff A. Bilmes <bilmes@ee.washington.edu>

Lecture 5 Slides

April 11th, 2006

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• Chordal graph theory• Elimination and chordality• Recognizing chordal graphs• How to triangulate a graph (heuristics)• Properties of conditional independence• Markov properties on graphs

Outline of Today’s Lecture

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Books and Sources for Today

• Jordan: Chapters 17.• Lauritzen, 1986. Chapters 1-3.• Any good graph theory text.

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• L1: Tues, 3/28: Overview, GMs, Intro BNs.• L2: Thur, 3/30: semantics of BNs + UGMs• L3: Tues, 4/4: elimination, probs, chordal I• L4: Thur, 4/6: chrdal, sep, decomp, elim• L5: Tue, 4/11: chdl/elim, mcs, triang, ci props.• L6: Thur, 4/13• L7: Tues, 4/18• L8: Thur, 4/20• L9: Tue, 4/25• L10: Thur, 4/27

• L11: Tues, 5/2• L12: Thur, 5/4• L13: Tues, 5/9• L14: Thur, 5/11• L15: Tue, 5/16• L16: Thur, 5/18• L17: Tues, 5/23• L18: Thur, 5/25• L19: Tue, 5/30• L20: Thur, 6/1: final presentations

Class Road Map

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• If you see a typo, please tell me during lecture– everyone will then benefit.– note, corrected slides will go on web.

• READING: Chapter 3 & 17 in Jordan’s book• Lauritzen chapters 1-3 (on reserve in library)• Check out CSE590AI this week (Weds, CSE609, 3:30-4:20)

– Compiling Relational Bayesian Networks for Exact Inference, by Mark Chavira, Adnan Darwiche, and Manfred Jaeger

– This is a “search” based method for inference of relational models, that pre-compiles such graph into logic equations. It has an implicit value-specific junction tree in it. We will be covering search based methods for inference in the upcoming weeks discussing what conditions are requried for them to help.

• Reminder: TA discussions and office hours:– Office hours: Thursdays 3:30-4:30, Sieg Ground Floor Tutorial

Center– Discussion Sections: Fridays 9:30-10:30, Sieg Ground Floor

Tutorial Center Lecture Room

Announcements

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Summary of Last Time

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Examples: decomposition tree and factorization

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Graph, decomposition tree, and junction tree

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How can we tell if G is chordal?

CompleteSet

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How can we tell if G is chordal?

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How can we tell if G is chordal?

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How can we tell if G is chordal?

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How can we recognize chordal graphs?

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Maximum Cardinality Search (MCS)

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Maximum Cardinality Search (MCS)

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How can we recognize chordal graphs?

1 2

3 41

2

3

4

5

6

78

9

10

11

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How can we recognize chordal graphs?

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MCS with Junction Tree

B

A

C

D

E F G

H I9 8

7 6

3

5

4

2

1

r.i.p. order:

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Elimination and Bayesian Networks

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Triangulation Heuristics

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Triangulation Heuristics

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Are all trees of maxcliques JTs?

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Are all trees of maxcliques JTs?

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Are all trees of maxcliques JTs?

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Are all trees of maxcliques JTs?

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Junction Trees -> Factorization

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Properties of Conditional Independence

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Properties of Conditional Independence

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Properties of Conditional Independence

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Properties of Conditional Independence

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Properties of Conditional Independence

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Properties of Conditional Independence

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Markov Properties of Graphs