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decision engine

noun [countable]

an Internet search engine that uses information from the user in order to provide more relevant results

'As part of a constant effort to improve their search engine algorithm, Bing has made a major change in what they call their decision engine. Search engine results from Bing will now include an adaptive feature … To explain this quite simply, your past search queries will be factored into current searches.'

Kingpin Webmaster News 16th September 2011

What do you get when you cross the concepts of speed dating and Internet search engines? Though at first glance it's difficult to see how they could possibly relate to one another, the latest generation of online search tools arguably lies somewhere at the intersection of the two. A search engine finds data. A decision engine, on the other hand, gets to know you first, and then finds the data most appropriate to you.

a search engine finds data. A decision engine … gets to know you first, and then finds the data most appropriate to you

A decision engine is basically a refinement of a web search engine that uses input from the user to work out what results will be more relevant and useful for them. A decision engine typically works in one of two ways. The first is to ask the user a series of questions designed to get them to specify particular criteria which will then be used to refine the search results. For example, if the user is looking at buying a television, they might be asked questions about screen size, manufacturer, requirements regarding HD or Internet video, etc. The decision engine then provides a list of hits that match the user's conditions, or otherwise ranks the hits carefully so that those which do not match the criteria so closely are given a much lower ranking. Alternatively, decision engines can also work by forming a longer term 'relationship' with the user by collecting data over time in order to establish their typical preferences. So, for example, if they were looking to buy a holiday but previously had exclusively looked at holidays in Spain, those results which offered holidays in other locations would not be placed so highly.

One of the most high-profile examples of a search tool now calling itself a decision engine, is Microsoft's Bing™, which refines search results by automatically organising them according to specific criteria which the user can then choose whether to focus on. It therefore guides the user into more effective searching by the categorization of data, but does not really provide personalized search results. Truer to the notion of the decision engine is the website Hunch, which asks a series of questions that help it work out what sort of person you are, and therefore what search results you'll want. Hunch also harnesses its users' collective intelligence, building knowledge bases from a pool of users with similar tastes.

Background – decision engine

The expression decision engine first appeared in 2009, and links closely with the concept of Web 3.0, the idea of the Internet becoming more 'intelligent' as it builds the capacity to make connections between the pieces of information it stores. The term decision engine is of course modelled on the earlier term search engine, which, contrary to what one might think, actually pre-dates the Internet by a few years, first appearing in the mid-eighties. In its first use, the term search engine described any kind of information retrieval system designed to help find information stored on a computer, but with the predominance of the Internet, its popular use has narrowed in meaning to software employed in the specific activity of searching for information on the Web.

by Kerry Maxwell, author of Brave New Words

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This article was first published on 3rd October 2011.

Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

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