The ANDs have it

August 27, 2007

This post was kindly contributed by Key Happenings at - go there to comment and to read the full post.

How many times a day do you perform a search on the Web? Do you have a favorite search site from which you start all of your searches? Does it drive you crazy that not all search engines are created the same?

Search tools have become a huge part of our everyday life. I search our intranet to locate an employee phone number, or to review the latest policy from HR. We use Internet search engines to locate the nearest pizza delivery shop, to plan home remodels, or to debug software error messages. Search engines have put the knowledge of the world at our fingertips and we expect a search to deliver the right answer every time.
The truth is that each search engine available today has a proprietary algorithm that determines which documents are returned, how they are ranked, and how they are rated. Once you become accustomed to your favorite search engine, you will feel like another search tools are failing if the assumptions, defaults, and ranking tools aren’t the same. We can’t do much to change the way the search engine works. However — here comes the good news — we have identified a few changes to address your requests.

And, the ANDs have it!
Currently, our search engine assumes and OR between two words. For years, we’ve given you this advice:

If you want a results set where the top-ranked files must contain all the words in your search, enter your string with plus signs: +data +mining +seminar

That works, but nobody does that. In almost every conversation we have with you, someone says “When I add a word to my search hoping to narrow the results, I get more results. That is not what I want.” I respond bashfully with “I know, but the search engine assumes an OR between each word.”

At your request, one of the first things that you will notice about searching the updated site is that submitting data mining will issue the query using ANDs. If you add a serminar to the end, your results will narrow to include documents that contain data and mining and seminar.

This post was kindly contributed by Key Happenings at - go there to comment and to read the full post.


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