Distribution ensemble

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In cryptography, a distribution ensemble or probability ensemble is a family of distributions or random variables where is a (countable) index set, and each is a random variable, or probability distribution. Often and it is required that each have a certain property for n sufficiently large.

For example, a uniform ensemble is a distribution ensemble where each is uniformly distributed over strings of length n. In fact, many applications of probability ensembles implicitly assume that the probability spaces for the random variables all coincide in this way, so every probability ensemble is also a stochastic process.

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