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Search Engines Essay

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There are currently over a billion pages of information on the Internet about every topic imaginable. The question is how can you possibly find what you want? Computer algorithms can be written to search the Internet but most are not practical because they must sacrifice precision for coverage. However, a few engines have found interesting ways of providing high quality information quickly. Page value ranking, topic-specific searches, and Meta search engines are three of the most popular because they work smarter not harder.

While no commercial search engine will make public their algorithm, the basic structure can be inferred by testing the results. The reason for this is because there would be a thousand imitation sites, meaning …show more content…

They realized that the most popular sites are those linked the most in other pages. Here is the pseudocode algorithm for searching:
1. Parse the query
2. Convert the words into wordIDs.
3. Seek to the start of the doclist in the short barrel for every word.
4. Scan through the doclists until there is a document that matches all the search terms.
5. Compute the rank of that document for the query.
6. If we are in the short barrels and at the end of any doclist, seek to the start of the doclist in the full barrel for every word and go to step 4.
7. If we are not at the end of any doclist go to step 4.
8. Sort the documents that have matched by rank and return the top k.

Each link to a page is like a vote for that page as well as the pages linked to that page. Thus a hierarchy of pages is created and the search results are much more reliable. Lycos and Excite also use the same system, but Google goes further. “It then looked at the position of the words on the page, the size of the fonts, and the likelihood that the words were related to each other” (1). Going the extra distance gives Google much better precision.

Google and engines like it can still be manipulated to achieve higher rankings. Anyone who creates a set of pages with links between them can fool the system and add value to their page. So the race continues to find yet another search engine. One promising way to search for

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