Hashing a Source With an Unknown
نویسنده
چکیده
R enyi entropy of order 2 characterizes how many almost uniform random bits can be extracted from a distribution by universal hashing by a technique known as \privacy ampliication" in cryptography. We generalize this result and show that if P S is the assumed distribution of a random variable with true distribution P X , then the amount of extractable almost uniform randomness corresponds to ? log PPX = S], when X and S are interpreted as independent random variables.
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تاریخ انتشار 1998