Google offers peek behind its search results

Recognizing that it's no longer the only search engine in town, Google recently shed some light on how it keeps tweaking its algorithms to improve its search results.

Last year, Google made more than 500 improvements to its search algorithms. In a blog published yesterday, Google Fellow Amit Singhal explained how each new change may be based on a clever idea. But if it doesn't pass the company's rigorous testing, it doesn't get added to the mix.

A video posted with the blog and displayed below tapped into comments from Google engineers, each offering their thoughts on how a change to an algorithm moves from initial idea to actual implementation.

As the first step toward improving the user's search experience, Google often starts with a set of current searches that aren't working as well as expected. Engineers then put their heads together to determine what data can be integrated into an algorithm to improve that particular type of search.

To test any new experiments made by engineers, Google relies on external people who've been trained to evaluate and compare different search rankings. Certain changes are also rolled out to a small number of actual users as part of a virtual sandbox. Last year alone, Google ran more than 20,000 different experiments.

A single analyst then analyzes the data from the tests and experiments, meets with other Google researchers, and discusses whether a certain change should be rolled out to all users.

"If our scientific testing says this is a good idea for Google users, we will launch it on Google," Singhal said in the video.

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As one example, Google has for many years offered spelling suggestions for search queries that it believes contain typos or other errors. In the past, the results would always respond with a "Did you mean?" question with the corrected spelling but would still show you the results based on the misspelled word. That would force users to click on the "Did you mean?" link to get the right results.

To better deal with typos, Google devised a new option that in many cases now shows the results based on the corrected spelling instead. But it gives users the ability to search based on the allegedly misspelled word, just in case it wasn't a misspelling.

Though Google is still the top major search engine by a wide margin, rival Bing has slowly been ekeing out more market share. And with the amount and complexity of data now online, search isn't quite as simple as it once was.

"As the Internet becomes bigger, richer, and more interactive it means that we have to work that much harder to ensure we're unearthing and displaying the best results for you," Singhal said in the blog.