How to Spy on Ryan (Moulton): Simple Simhashing, My favorite trick.

Thursday, October 01, 2009

Simple Simhashing, My favorite trick.

Knol got equation editing a few days ago, and to celebrate I've written up a knol on one of my favorite CS tricks, simhashing using sets. It's a technique I picked up at Google, and it's extremely useful for grouping together similar things in a large dataset.

Suppose you have a huge number of items that you would like to group together by a fuzzy notion of similarity. Suppose the only tool available to you is a key-value store. Suppose you only have the resources to consider each object once. Never fear, simhashing is here!

3 comments:

Anonymous said...: Wow. Neat! Thank you -- I had never seen this.; 8:10 AM
Unknown said...: Hi Ryan,
It seems I'm a few date too late to read your article on knol.
Do you have a copy of the article somewhere else?

Regards,
Markus; 6:35 AM
Ryan Moulton said...: Thanks for the note! I've updated the link to the new location.; 9:41 PM

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How to Spy on Ryan.

Thursday, October 01, 2009

Simple Simhashing, My favorite trick.

3 comments:

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