CPSC 536N: Sparse Approximations

General Information

Course Website: http://www.cs.ubc.ca/~nickhar/W13

Lecture Time: Mondays & Wednesdays, 9:30am-11:00am

Lecture Room: ICICS 206

Instructor: Prof. Nicholas Harvey, X851, nickhar@cs.ubc.ca

 

This is a graduate course on algorithm design. We will explore two branches of this field: combinatorial optimization algorithms and spectral algorithms. The ultimate goal of the course is to explore the theme of “sparse approximations” in graph theory. We will discuss thin trees, thin forests, expanders and graph sparsifiers.

 

Syllabus

 

Lectures

 

Date

Topics

Scribe

References

1

1/2

Review of linear programming

Nick Harvey: PDF

My slides PPTX, PDF

Goemans' notes pages 1-5

Combinatorial Optimization Appendix A
Theory of Linear and Integer Programming 7.2, 7.4, 7.5

2

1/7

Strong duality, Fourier-Motzkin Elimination, Farkas' Lemma

Samira Samadi: PDF

My slides PPTX, PDF

Goemans' notes pages 1-5

Understanding and Using Linear Programming 6.4, 6.7
Theory of Linear and Integer Programming 7.1, 7.3, 7.4

3

1/9

Extreme points

Daniel Busto: PDF

My slides PPTX, PDF

Goemans' notes pages 5-10

Theory of Linear and Integer Programming 8.3, 8.4, 8.5

4

1/14

The Ellipsoid Method

Alex Frechette: PDF

My Slides PPTX, PDF, My extra notes PDF

Goemans' notes pages 1-6

Boyd’s slides, Boyd’s lecture, Boyd’s lecture continuation

Theory of Linear and Integer Programming Ch 13, 14

5

1/16

Integer programs, Total unimodularity, Max-flow Min-cut

Samira Samadi: PDF

My Slides PPTX, PDF

Goemans' notes pages 13-17

Goemans' notes pages 1-6

Combinatorial Optimization 3.2, 6.5

6

1/21

Min cost cycle cover, Asymmetric TSP

Zachary Drudi: PDF

Chekuri's slides 21-39

Frieze, Galbiati, Maffioli, Section 6

7

1/23

Contraction algorithm for minimum cut

Nick Harvey: PDF

Combinatorial Optimization pages 76-78

8

1/28

LP relaxation of ATSP

Daniel Busto: PDF

Goemans et al paper

My notes on Chernoff bounds

9

1/30

Randomized rounding for ATSP 

Gabriel Goh: PDF

Goemans et al paper

Combinatorial Optimization: Polyhedra and Efficiency Ch. 11

10

2/4

The spanning tree polytope

Alex Frechette: PDF

Combinatorial Optimization p15-17

11

2/6

Pipage rounding

Alex Frechette: PDF

Vondrak's notes

12

2/13

Thin trees via pipage rounding

Noushin Saeedi: PDF

Asadpour et al paper

Chekuri et al paper

13

2/25

O(log n / log log n) approximation for ATSP 

Zachary Drudi: PDF

Asadpour et al paper

 

14

2/27

The Laplacian of a graph

Gabriel Goh: PDF

My notes on symmetric matrices

My notes on the graph Laplacian

15

3/4

Thin forests

Gabriel Goh: PDF

 

16

3/6

Thin forests

Zachary Drudi: PDF

Using ideas from the Batson et al paper

17

3/11

Definition of expanders

Monir Hajiaghayi: PDF

Hoory et al survey, Spielman's notes

18

3/13

Algorithm to construct expanders

Daniel Busto: PDF

Using ideas from the Batson et al paper

19

3/18

Graph sparsifiers

Samira Samadi: PDF

Batson et al paper

20

3/20

Approximation for Max Cut

Alex Frechette: PDF

Trevisan's paper

21

3/25

Random matrices

Zachary Drudi: PDF

Tropp's paper, Tropp's survey, My notes on symmetric matrices

22

3/27

Tropp's inequality

Zachary Drudi: PDF

Tropp's paper, Tropp's survey

23

4/3

Random graph sparsifiers

Samira Samadi: PDF

Spielman's notes on effective resistances

 

The topics that we hoped to cover but couldn't fit in are:

·         Matroids, Matroid Polyhedra, Graph skeletons, Cut sparsifiers, Negatively dependent distributions, Cheeger's inequality