MAD method compression function

Posted by Jacques on Stack Overflow See other posts from Stack Overflow or by Jacques
Published on 2010-06-10T18:01:49Z Indexed on 2010/06/10 18:22 UTC
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I ran across the question below in an old exam. My answers just feels a bit short and inadequate. Any extra ideas I can look into or reasons I have overlooked would be great. Thanx

Consider the MAD method compression function, mapping an object with hash code i to element [(3i + 7)mod9027]mod6000 of the 6000-element bucket array. Explain why this is a poor choice of compression function, and how it could be improved.

I basically just say that the function could be improved by changing the value for p (or 9027) to an prime number and choosing an other constant for a (or 3) could also help.

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