Why does Google do this?

[not_alice]

@PatriotGrrrl

I have repeatedly (on different message boards etc.) offered to pay anyone who can find me a search engine that only finds exactly the string of characters I entered (including whitespace and punctuation), and to pay (either per use or subscription) to use such a site.

I’ve never gotten any real results.

(Yes, I realize there are technical difficulties with this, due to the nature of html.)

There is nor really any technical difficulty to building such an index, only that 15 years or so of experience has shown that it is an ineffective way to search a large heterogeneous set of documents.

While the earliest yahoo attempts at indexing may have been built that way, it was not long before academic research and actual practice moved away from that approach.