Google Director of Research Peter Norvig recently answered questions about Google’s search algorithms. Norvig stated, “We test tens of thousands of hypotheses each year, and make maybe one or two actual changes to the search algorithm per day. That’s a lot of ideas, and a lot of changes. It means the Google you’re using this year is improved quite a bit from the Google of last year, and the Google you’re using now is radically different from anything you used ten years ago.”

He continued, “If you define A.I. as providing a course of action in the face of uncertainty and ambiguity, based on learning from examples, that’s what our search algorithm is all about. I’d say the resulting technology — Google Search as a whole — is a form of A.I. If you define A.I. as providing a course of action in the face of uncertainty and ambiguity, based on learning from examples, that’s what our search algorithm is all about.”

Norvig added, “The search engine has to understand what’s out on the web in text and other forms like images, books, videos, and rapidly changing content like news, and how it all fits together. Then it has to try to infer what the user is looking for, sometimes from no more than a keystroke or two. And then it has to weigh hundreds of factors against each other — hundreds of signals, like the links between content, the correlations among phrases, the location of the search, and so on — and provide the user information that’s relevant to their query, with some degree of confidence for each piece. And finally it has to present that information in a coherent, useful way. And it has to be done potentially for each keystroke, since Google results update instantly now.”

Read more here.

Image: Courtesy Google