Sourced From SearchDayDogpile has redesigned its meta search site and introduced a nifty new utility that visually displays the overlap (or lack thereof) of results from the multiple search engines it queries.

The primary focus of the redesign is on result pages, which now present twenty “best of breed results from the top search engines,” ranked by blending results from a number of search engines using Dogpile’s own relevance algorithms. The engines searched include algorithmic results from Google, Yahoo and Ask Jeeves, sponsored listings from Google, Overture and Looksmart, and other listings from About and Dogpile’s own “web search picks.”

While this isn’t too different from the way Dogpile used to display results, a cool new feature lets you simultaneously display blended results side-by-side with results from one or more individual search sources by clicking a button at the top of the result page. Results from an individual source open in a window to the right of the blended results, and you can open up results from every source other than Dogpile’s web search picks simultaneously.

This makes it easy to directly compare the top results from these different engines. Dogpile has taken this a step further by highlighting results that are unique to the first result page for each engine. For example, if a result shows up in the first page of a Yahoo search but not in any other search source, it is shaded with a pale yellow background. You can turn this highlighting on or off using a check box at the top of the result list.

The intent is to visually demonstrate the value of meta search by showing the lack of overlap in the top results of the major search engines, according to Brian Bowman, Vice President of Marketing and Product Management for Infospace, which owns Dogpile.

By comparing results side-by-side, it quickly becomes apparent that each search engine has its own unique view of the web. If you rely on a single source for search results, you’re often missing a significant chunk of the web.

Dogpile has gone a step further to let you explore search engine overlap on your own. In conjunction with the new design, Dogpile has released a new ” missing pieces tool” that visually displays the similarities and differences between Ask Jeeves, Google and Yahoo search results for the same query.

The tool is a flash application that displays icons on a circular grid representing pages found on only one, two or all three engines. Mouse over an icon and the underlying URL is displayed. Paw prints displayed within an icon show Dogpile’s top results, those that would be displayed in a blended result page from a meta search.

The missing pieces tool combines the best features of jux2 (winner of the Search Engine Watch 2004 best meta search engine award) and the thumbshots ranking tool. Together with Dogpile search results, the missing pieces tool offers a great, easy way to explore search engine overlap.

New Search Engine Overlap ResearchDogpile also released a brief report (PDF format) of a study that examined search engine overlap among Ask Jeeves, Google and Yahoo.

Two key findings: With a sample of more than 10,000 queries, 86% returned a different #1 ranked algorithmic result in each search engine, and 32% of these queries did not return any overlapping results in the top three algorithmic positions.

These findings are significant for both searchers and search marketers. If you’re relying on just one search engine for your information needs, you’re missing a lot. And if you are a search marketer optimising content for just one engine, you’re also not likely to appear in the top results of other engines, meaning you’re missing out on significant potential web site traffic.

Several other findings were reported, but they tend to muddy the waters rather than offer new insights, because the numbers consider both algorithmic and paid listings together. Looked at this way, just 3% of all paid and algorithmic results were shared by all three engines. Dogpile says this illustrates why meta search is so important, because 3% represents such scant overlap.

But this number isn’t an apples-to-apples comparison. Unlike the findings for algorithmic results, which compare the same web pages found in different search engine indexes, it’s virtually impossible to compare paid listing results across engines and draw meaningful conclusions.

Why? The reasons are numerous. First and foremost, the number of paid listings displayed varies both by engine and depending on the query. Advertisers also have significant control over when and how listings are displayed, using various matching options, geotargeting or day-parting strategies (where ads are displayed only at certain times of the day). Furthermore, advertisers may actually be showing up in top results across different engines using different ad copy, landing page URLs and so on—so there may be more overlap than actually reported.

Therefore, the 3% overlap figure should be taken with a huge grain of salt. The overlap numbers reported for algorithmic results alone are far more useful and credible.

Quibbling aside, the newly redesigned Dogpile is a significant improvement over the previous version, and the missing pieces tool provides a valuable view of search engine overlap.