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Closures of exponential families

Imre Csiszar·Frantisek Matus
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Abstract

The variation distance closure of an exponential family with a convex set of canonical parameters is described, assuming no regularity conditions. The tools are the concepts of convex core of a measure and extension of an exponential family, introduced previously by the authors, and a new concept of accessible faces of a convex set. Two other closures related to the information divergence are also characterized.

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Imre Csiszar, Frantisek Matus. 2005-03-29. Closures of exponential families. https://doi.org/10.1214/009117904000000766

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