How Search-Engine Rules Cause Sites to Go Missing

HOW SEARCH-ENGINE RULES CAUSE SITES TO GO MISSING
[SOURCE: Wall Street Journal, AUTHOR: Kevin J. Delaney kevin.delaney@wsj.com]
The influence of search engines has only grown in recent years, as they have become the de facto gateways for many of the more than 180 million American Internet users to anything they might do online. They also have become a crucial tool for businesses that depend on those users finding them. But as a way to lure customers to a site, search rankings often aren't dependable. Overnight, sites can disappear from top results for any given search term -- say, "Miami hotels" -- and cause the sites' revenues plummet as potential customers go elsewhere. Among the most common reasons for unpredictable changes in rankings are frequent updates to search engines' algorithms. These mathematical formulas analyze billions of Web pages for dozens of factors, such as the most prominent words on the pages and what other sites link to the pages, in order to determine how to rank them for relevance to a query. Search companies change algorithms partly to frustrate people who try to inappropriately boost their sites in the results, but legitimate businesses sometimes feel they're caught in the crossfire.
http://online.wsj.com/article/SB117375265591935029.html?mod=todays_us_marketplace
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