Computer Science 690 Probabilistic Analysis of Algorithms and Data Structures Winter 2026 --- Course Syllabus
Instructor	Luc Devroye | Email | McConnell Engineering Building, Room 300N | Live office hours, Tuesday and Thursday, 10-11am.
Location and time	Tuesday and Thursday, 8:30--10am. Lectures start on Tuesday, January 6, 2026 and run until Thursday, April 9, 2026. No lectures between March 2 and 6 (reading week). We meet in McConnell 321 (the lounge). Course notes will be handed out in class.
Teaching Assistant	Caelan Atamanchuk, McConnell Engineering 310/311. Email Caelan. Office hours: Monday, 12-2 pm.
Description	This course looks at basic methods for analyzing the average behavior of algorithms and data structures. It is shown how conventional and modern probability theoretical techniques can be used in this respect. The list of topics does not pretend to be exhaustive; rather, it is selected to give a broad horizontal view of possible applications. The students should be familiar with elementary concepts in probability theory and data structures.
Contents	Binary search trees Connection with the theory of records and random permutations. Analysis of depth and height. Quadtrees, k-d trees, union-find trees. The uniform random recursive tree. Preferential attachment trees. Introduction to branching processes, branching random walks. Branching processes Analysis of simple families of random trees. Galton-Watson trees. Random graphs Simple random graph models, independent sets, coloring. The second moment method. Analysis of simple heuristics for graph problems. The Erdös-Rényi theorem on connected graphs. Random geometric graphs, the Gilbert disc model, percolation. Randomized algorithms Introduction to the methodology. Finding the k-th largest quickly on the average. Randomized routing on networks. Exponential large deviation inequalities. Closest point problems. Random incremental algorithms. Randomized approximation algorithms. Combinatorial search problems Euclidean traveling salesman problem. Assignment problems. Martingales and the bounded differences method. Concentration inequalities. Markov chains Basic properties. Markov chain Monte Carlo. Generating random combinatorial objects. Rapid mixing. Mixing time. Entropy Entropy, coding and compression. Entropy and random tries. Digital search trees. The probabilistic method Lovasz local lemma. Janson's inequalities.
Evaluation	About seven sets of theoretical problems will be assigned.
Textbook	There is no specific textbook. Course notes will be handed out.
Selected references	Some references are given below. N. Alon, J. Spencer, and P. Erdös, The Probabilistic Method, John Wiley, New York, 1992. The Fourth Edition of this book, without Erös, was published in 2016. B. Bollobas, Random Graphs, Academic Press, New York, 1985. Second edition from 2001. L. Devroye, "Branching processes in the analysis of the heights of trees," Acta Informatica, vol. 24, pp. 277--298, 1987. L. Devroye, "Applications of the theory of records in the study of random trees," Acta Informatica, vol. 26, pp. 123--130, 1988. S. Janson, T. Luczak, A. Rucinski, Random Graphs, Wiley-Interscience, New York, 2000. R. M. Karp, "The probabilistic analysis of some combinatorial search algorithms," in: Algorithms and Complexity, ed. J. F. Traub, pp. 1--19, Academic Press, New York, 1976. R. M. Karp and J. M. Steele, "Probabilistic analysis of heuristics," in: The Traveling Salesman Problem: A Guided Tour of Combinatorial Optimization, ed. E. L. Lawler, J. K. Lenstra, A. H. G. Rinnooy Kan and D. B. Shmoys, pp. 181--205, John Wiley, New York, 1985. D. E. Knuth, The Art of Computer Programming, Vol. 3 : Sorting and Searching, Addison-Wesley, Reading, Mass, 1973. H. M. Mahmoud, Evolution of Random Search Trees, John Wiley, New York, 1992. R. Motwani and P. Raghavan, Randomized Algorithms, Cambridge University Press, 1995. E. M. Palmer, Graphical Evolution, John Wiley, New York, 1985. J. Pearl, Heuristics. Intelligent Search Strategies for Computer Problem Solving (Chapter 5), Addison-Wesley, Reading, Mass, 1984. W. Szpankowski, Average Case Analysis of Algorithms on Sequences, Springer-Verlag, New York, 2001. J. S. Vitter and P. Flajolet, "Average-case analysis of algorithms and data structures," in: Handbook of Theoretical Computer Science, Volume A: Algorithms and Complexity, ed. J. van Leeuwen, pp. 431--524, MIT Press, Amsterdam, 1990.