C&O 750: Randomized Algorithms

General Information

Course Website: http://www.math.uwaterloo.ca/~harvey/W11/

Lecture Time: Tuesdays & Thursdays, 11:30am-12:50pm

Lecture Room: MC 4042

Instructor: Prof. Nicholas Harvey, MC 6068, harvey@math.uwaterloo.ca

 

Syllabus

 

Project Information

 

Assignments

·         Assignment 1, due Thursday January 27th.

·         Assignment 2, due Thursday March 11th.

·         Assignment 3, due Thursday March 31st.

 

Lecture Topics

 

Date

Topics

Reading in Textbooks

1

1/4

Review, Max Dicut, Markov's inequality

MU 1.2, 2.1-2.4, 3.1

2

1/6

Amplification by independent trials, Chernoff bound, Union bound, Balls and bins

MU 4.1-4.2 & 5.2, MR 4.1 & 3.1, DP 1 & 2.2, AS App. A

3

1/11

Randomized complexity classes, BPP amplification, BPP has polynomial size circuits

MR 1.5 & 2.3

4

1/13

Congestion minimization, Discrepancy, Codes of large distance

MU 4.4, MR 4.1 & 4.3,
AS 13.1

5

1/18

Dimensionality reduction by the Johnson-Lindenstrauss lemma

DP 2.5

6

1/20

Estimating L2-norm in data streams, Nearest neighbours in high dimensions

7

1/25

Schwartz-Zippel Lemma, Polynomial identity testing

MR 7.2

8

1/27

Kakeya sets

9

2/1

Minimum cuts via contractions

MU 1.4, MR 1.1 & 10.2

10

2/3

Graph skeletons and sparsifiers

11

2/8

Concentration for matrices by the Ahlswede-Winter inequality

My Notes

12

2/10

Spectral sparsifiers

13

2/15

Chebyshev's inequality, Pairwise independence

MU 3.2-3.3, 13.1-13.2

14

2/17

Perfect hashing, NP-complete problems with unique solutions

MU 13.3-13.4, MR 8.5

15

3/1

Martingales, Concentration by Azuma’s inequality

MU 12.1 & 12.4, MR 4.4,
AS 7.1-7.2, DP 5.1-5.2

16

3/3

Method of bounded differences, Balls and bins, chromatic number.
An algorithmic version of the Lovász Local Lemma applied to k-SAT.

MU 12.5, MR 4.4.3-4.4.4, AS 7.2, 7.4-7.5, DP 5.3-5.4 & 6.3

17

3/8

Online bipartite matching

18

3/10

Expanders and super concentrators

19

3/15

Random partitions of metric spaces

20

3/17

Random embeddings of metric spaces into trees

21

3/22

Embedding metric spaces into L1, Sparsest Cut

22

3/24

Rounding the Leighton-Rao Relaxation. Low congestion trees.

23

3/29

Low congestion trees, Bisection

24

3/31

Non-bipartite matching

My Slides

 

Further Reading

Review of Discrete Probability

E. Lehman, F. T. Leighton and A. Meyer. Mathematics for Computer Science. Ch 14-18.

 

Chernoff Bound

C. McDiarmid. Concentration. Sections 1 & 2.

 

Balls and Bins

M. Raab and A. Steger. “Balls into Bins” - A Simple and Tight Analysis.

 

Randomized Complexity Classes

S. Arora and B. Barak. Computational Complexity: A Modern Approach. Chapter 7.

M. Sudan. Advanced Complexity Theory. Lecture 10 and Lecture 11.

 

Circuits

S. Arora and B. Barak. Computational Complexity: A Modern Approach. Chapter 6.

M. Sudan. Advanced Complexity Theory. Lecture 3.

 

Congestion Minimization

D. Williamson and D. Shmoys. The Design of Approximation Algorithms. Section 5.11.

 

Codes

M. Sudan. Coding Theory. Lecture 1 and Lecture 9.

 

Dimensionality Reduction by Johnson-Lindenstrauss

M. Goemans. Metric Embeddings. Lecture 1 and Lecture 6.

A. Gupta and R. Ravi. Algorithmic Applications of Metric Embeddings. Lecture 15.

 

Data Streams

P. Indyk. Sketching, Streaming, and Sub-linear Space Algorithms. Lecture 2.

P. Indyk. Geometric Computation. Lecture 17.

 

Nearest Neighbors

P. Agarwal. Geometric Optimization. Lecture 25.

P. Indyk and R. Motwani. Approximate Nearest Neighbors: Towards Removing the Curse of Dimensionality. STOC 1998.

 

Schwartz-Zippel & Polynomial Identity Testing

R. Lipton. The Curious History of the Schwartz-Zippel Lemma. Blog post from Gödel's Lost Letter and P=NP.

V. Kabanets. Pseudorandomness. Lecture 2.

 

Matching Algorithms

L. Lovasz. On determinants, matchings and random algorithms. FCT 1979.

 

Kakeya Sets

T. Tao. Dvir’s Proof of the finite field Kakeya conjecture. Blog post from What’s new.

Z. Dvir. From randomness extraction to rotating needles. SIGACT News 2009.

Z. Dvir. On the size of Kakeya sets in finite fields.

 

Minimum Cuts and Graph Skeletons

D. Karger. Random Sampling in Cut, Flow and Network Design Problems. STOC 1994. Section 2 and Appendix A.

 

Sparsifiers

A. Benczur and D. Karger. Randomized Approximation Schemes for Cuts and Flows in Capacitated Graphs. STOC 1996.

 

Concentration for Matrices by Ahlswede-Winter

R. Vershynin. A note on sums of independent random matrices after Ahlswede-Winter.

T. Tao. The Golden-Thompson Inequality. Blog post from What’s new.

 

Spectral Sparsifiers

D. Spielman and N. Srivastava. Graph Sparsification by Effective Resistances. STOC 2008.

 

Pairwise Independence

M. Luby and A. Wigderson. Pairwise Independence and Derandomization. Sections 1, 2, 3.2.

 

Martingales

J. Snell. Gambling, probability and martingales.

R. Mansuy. The Origins of the Word “Martingale”.

C. McDiarmid. Concentration. Sections 3.1 & 3.3.

 

Lovász Local Lemma

L. Fortnow. A Kolmogorov Complexity Proof of the Lovász Local Lemma. Blog post from Computational Complexity.

T. Tao. Moser’s entropy compression argument. Blog post from What’s new.

R. Moser and G. Tardos. A constructive proof of the general Lovasz Local Lemma. JACM 2010.

 

Online Bipartite Matching

B. Birnbaum and C. Mathieu. On-line Bipartite Matching Made Simple. SIGACT News 2008.

R. Karp, U. Vazirani and V. Vazirani. An Optimal Algorithm for On-line Bipartite Matching. STOC 1990.

 

Expander Graphs

S. Hoory, N. Linial and A. Wigderson. Expander Graphs and Their Applications. Chapter 1.

 

Low Diameter Partitions

J. Lee. Random Partitions of Metric Spaces. Blog post from tcs math.

G. Calinescu, H. Karloff and Y. Rabani. Approximation Algorithms for the 0-Extension Problem. SODA 2001.

 

Random Embeddings into Trees

J. Lee. Random tree embeddings. Blog post from tcs math.

J. Fakcharoenphol, S. Rao, K. Talwar. A Tight Bound On Approximating Arbitrary Metrics By Tree Metrics.

J. Fakcharoenphol, S. Rao, K. Talwar. Approximating metrics by tree metrics. STOC 2003.

D. Williamson and D. Shmoys­. The Design of Approximation Algorithms. Section 8.5.

 

Sparsest Cut

L. Trevisan. The Leighton-Rao Relaxation. Blog post from in theory.

D. Williamson and D. Shmoys. The Design of Approximation Algorithms. Section 15.1.

 

Low Congestion Trees & Graph Bisection

R. Andersen and U. Feige. Interchanging distance and capacity in probabilistic mappings.

D. Williamson and D. Shmoys. The Design of Approximation Algorithms. Section 15.2 and Section 15.3.

H. Räcke. Optimal Hierarchical Decompositions for Congestion Minimization in Networks. STOC 2008.

 

Non-bipartite Matching

N. Harvey. Algebraic Algorithms for Matching and Matroid Problems. FOCS 2006.