Creating a test set with a hash (Issue 71 was closed)

Hi, I did read issue #71 "Creating test set with hash" and I only had one question concerning your explanation.

During the hashing, only the last byte of the actual hash is considered as the test in order to determine if the data in question belongs to the test set. Yes, the whole hash is a unique value (unless a collision happens). But, only the last byte 0-255 is used as the determinant of belonging in the data set. So, are you saying that because the hashing algorithm provides a "uniform distribution" that 20% of the values that represent the last byte of the hash will be less than 51 (20% of 256)?

Thank You
Tom

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