FOUNDS SEMINAR SERIES TALK 08 - Information Theoretic Converses via Change of Measure

Title : Information-Theoretic Proofs based on Change of Measure Arguments

Abstract : We will be presenting information-theoretic proofs based on change of measure arguments for basic source coding and hypothesis testing problems, and if time permits also for channel coding. For the basic source and channel coding setups, the proofs only use a change of measure argument on the strongly typical set and are established solely by analyzing the asymptotic behaviour of the new measure. This proof method is also extended to a source coding setup under the relaxed expected-rate constraint, in which case the minimum compression rate depends on the allowed probability of error $\epsilon$ and an $\epsilon$-dependent converse is required. In the second part of the talk we present converse proof methods for hypothesis testing setups, where in addition asymptotic Markov Chains need to be established.