Exponential Families of Probability Measures
14 Nov 2011 20:53
I should explain what these area, but having done so elsewhere, I am feeling disinclined to do it again. (Later, I should just copy that text.)
I am particularly interested in exponential families for time series (very natural for Markov models) and for networks. More generally, if I have a family of stochastic processes (collections of dependent random variables) which form exponential families, what constraints does that put on the process?
Exponential families correspond to canonical ensembles in statistical mechanics. (Natural sufficient statistics : natural parameters :: extensive macroscopic variables : conjugate intensive variables.) In statistical mechanics, one of the justifications for using canonical ensembles for large systems comes from large deviations theory. Is there something equivalent in statistics proper? (Roussas's results on local asymptotic approximation of parametric models by exponential families feels like it should be connected here.)
See also: Information geometry; Large deviations; Maximum entropy; Statistical mechanics; Statistics in general; Sufficient statistics
- Recommended, big picture:
- Lawrence D. Brown, Fundamentals of Statistical Exponential Families: with Applications in Statistical Decision Theory [All you ever wanted to know, really. Now open access.]
- Benoit Mandelbrot, "The Role of Sufficiency and of Estimation in Thermodynamics", Annals of Mathematical Statistics 33 (1962): 1021--1038 [Still one of the best discussions of the interplay between formal, statistical and substantive motivations for exponential families.]
- Mark Schervish's Theory of Statistics [Exponential families are central enough to statistical theory that any good textbook will have decent coverage of the same key topics, but I found Mark's treatment particularly clear and streamlined before he became my department chair.]
- Recommended, close-ups:
- Peter Guttorp, Stochastic Modeling of Scientific Data [Gives nice discussions and examples of using exponential families, and their properties, to model dependent data]
- Rudolf Kulhavy, Recursive Nonlinear Estimation: A Geometric Approach [Emphasizing information-geometric aspects]
- Steffen L. Lauritzen
- Extremal Families and Systems of Sufficient Statistics [Mini-review.]
- "Extreme Point Models in Statistics", Scandinavian Journal of Statistics 11 (1984): 65--91 [Highlights of the book, without proofs but with decent typography. Includes some of his very interesting algebraic extensions to the usual notions of exponential families. JSTOR]
- George G. Roussas, Contiguity of Probability Measures: Some Applications in Statistics [Asymptotic theory of exponential-family approximation, estimation and testing, for discrete-time Markov processes on fairly general state-spaces. Mini-review]
- Modesty forbids me to recommend:
- CRS and Alessandro Rinaldo, "Consistency under Sampling of Exponential Random Graph Models", arxiv:1111.3054 [Our results are actually about exponential families of stochastic processes in general, though inspired by and applied to puzzles arising from the ERGM situation]
- To read:
- O. E. Barndorff-Nielsen, Information and Exponential
Families
- Imre Csiszar and Frantisek Matus, "Closures of exponential families", Annals of Probability 33 (2005): 582--600 = math.PR/0503653
- J. L. Denny, "Sufficient Conditions for a Family of Probabilities to be Exponential", Proceedings of the National Academy of Sciences 57 (1967): 1184-- ["We make the following statement precise under fairly weak conditions: in an experiment, if we summarize n statistically independent observtions (x1,...xn) in m < n real numbers (y1,...ym), where yj = \sumi=1nfj(xi) and the fj are given functions, and if we assume we have lost no information by the summary, then the family of probabilities associated with the experiment must be an exponential family."]
- Sham Kakade, Ohad Shamir, Karthik Sindharan, Ambuj Tewari, "Learning Exponential Families in High-Dimensions: Strong Convexity and Sparsity", Journal of Machine Learning Research Proceedings 9 (2010): 381--388
- Uwe Küchler and Michael Sørensen, Exponential Families of Stochastic Processes
- Richard Lockhart and Federico O'Reilly, "A note on Moore's conjecture", Statistics and Probability Letters 74 (2005): 212--220 ["We establish the conjecture of Moore ... that the usual plug-in estimate of a distribution function and the Rao-Blackwell estimate of the distribution function are asymptotically equivalent for a wide class of exponential family distributions."]
- Frank Nielsen, "Chernoff information of exponential families", arxiv:1102.2684
- Martin J. Wainwright and Michael I. Jordan, "Graphical Models, Exponential Families, and Variational Inference", Foundations and Trends in Machine Learning 1 (2008): 1--305 [PDF reprint via Prof. Jordan]
- To write:
- CRS, "Exponential Families of Stochastic Automata and Their Mixtures"
- CRS + Co-conspirators to be named later, "Projective Structure and Parametric Inference in Exponential Families"
