COMPUTATIONAL METHODS IN STATISTICS STA 4102/5106: Spring 2002 Instructor: Dr. Anuj Srivastava (Room OSB 210B/106D, 644-8832) http://stat.fsu.edu/~anuj Location: Room 205 OSB, MWF 10:10-11:00am Course Objective: To gain an understanding of the techniques and ideas used in implementing mathematical formulations on computers, with focus on common statistical approaches. The main computational tool will be Matlab. Prerequisites: Probability theory (discrete and continuous random variables), linear algebra, and real analysis. Texts: 1. Elements of Statistical Computing: Numerical Computation, Ronald A. Thisted (Chapman & Hall, 88) 2. Numerical Analysis: A Practical Approach, M. J. Maron (Macmillan Publishing Company, 82). 3. Matrix Computations, Golub and VanLoan (Johns Hopkins University Press, 96). 4. Simulation by Sheldon Ross, Second Edition, Academic Press, 1997. 5. Monte Carlo Statistical Methods by C. P. Robert and G. Castella, Springer Text in Statistics, 1999. 6. Random Number Generation and Monte Carlo Methods by James Gentle Topics Covered: 1. Numerical Analysis: Floating point arithmetic and error analysis. 2. Numerical Linear Algebra: Multiple regression analysis, orthogonalization by Householder transformations. 3. Nonlinear Methods: root finding, numerical optimization. 4. Numerical Integration: Quadrature integration, Newton-Cotes’ method, Composite rules 5. Random Number Generators: modular arithmetic, linear congruential generators combination generators 6. Monte-Carlo methods for Integration: a. General MC formulation: sample mean and variance b. Importance sampling (ex: Cauchy), optimal choice of sampling density c. Variance reduction techniques: antithetic variables, control variates, variance reduction by conditioning, importance sampling via twisted simulations. 7. Markov chain Monte-Carlo (MCMC) methods: a. Introduction to stochastic processes (ex: Poisson counting process, Random Walk and its limiting case), Markov process, stationarity, homogeneous Markov process, b. Finite-state case: Markov chain, transition matrix, Perron-Frobenious theorem, irreducibility and aperiodicity, ergodic result c. Countable-state case: recurrence, basic limit theorem of Markov chains, positive recurrent, ergodicity d. Metropolis-Hastings: general algorithm, detailed balance condition, independent Metropolis-Hastings, random walk Metropolis-Hastings. e. Gibbs Sampler: general algorithm, bivariate Gibbs sampler, completion Gibbs sampler (ex: truncated normal), slice sampler. Grading Policy: 50% homework, 20% mid-term, 25% final and 5% class participation and quizzes (grading will be relative) Homework: It will be assigned Wednesday every week and will be due the next Wednesday. Late assignments will not be accepted. The assignment with lowest grade will be dropped. Please write clear and detailed answers to the homework problems. If a problem involves writing a program, submit a copy of the code with the solution. Provide illustrative outputs of your programs to accompany the homework solutions. Attendance Policy: It is required to attend all the classes. It is the student’s responsibility to understand the material covered in the class during any absence. Academic Honor System: “The Academic Honor System of The Florida State University is based on the premise that each student has the responsibility to: 1) Uphold the highest standards of academic integrity in the student’s work, 2) Refuse to tolerate violations of academic integrity in the academic community, and 3) Foster a high sense of integrity and social responsibility on the part of University community.” Please note that violations of this Academic Honor System will not be tolerated in this class. Specifically, incidents of plagiarism of any type or referring to any unauthorized material during examinations will be rigorously pursued by this instructor. Before submitting any work for this class, please read the “Academic Honor System” in its entirety (as found in the FSU General Bulletin and in the FSU Student Handbook) and ask the instructor to clarify any of its expectations that you do not understand).