[I've sent a fuller reply to Jon in private mail.] JonWienke@aol.com writes:

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Actually, it doesn't. The entropy present from a reasonable source like keyclick timings is much much lower than the output of pkzip is going to suggest to you.

I am not saying that the output of the compression function has 8 bits of entropy per byte, but rather that it will have a more consistent entropy level per byte than the input to the function.

What makes you think that? There is little to no cause to expect this at all. I can think of a number of instances, like image data streams, where this idea is completely unfounded for most conventional compression techniques. Perry