I think, I'm applying a human perspective on information retrieval here. I didn't even thought about something as exact as hashing.
Although I remember some digests, could've been TEA, actually behave like the data I was referring to. Hashes begin to differ more when the underlying data differs more. Like 
"Foo a" would hash to "a1b2c3d4", and
"Foo b" would hash to "a1b2c3d5"
- they are similar to a certain degree. A query for "a1b2c3d*" in a similar as the proposed system would return both. But the example requires the properties to adhere to a certain order.

Back to the "human perspective": what I have in mind is something like "is this your car?", you begin to apply filters: right color, make, etc. But how sure can you be, ever? "Matching" in life is an approximatory process - question is: how do I implement that as an algorithm?

In reply to Re^2: What is the best way to store and look-up a "similarity vector"? by isync
in thread What is the best way to store and look-up a "similarity vector" (correlating, similar, high-dimensional vectors)? by isync

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