• Some resume categories other than technical are more common online.
• If you search for resumes by filetype -- which is a good practice if you want to eliminate job postings and other garbage from your results -- there are some non-intuitive choices that apparently work better than PDF and DOC
• you can't just use one major search engine for resume search, because the most popular search engine overall isn't necessarily going to find you as many resumes as other major engines (and for some resume categories, the difference is apparently stark).

Though not with resume search in mind, that last bullet was already proven for me almost two years ago, shortly after a Web Search University conference where noted e-researcher Gary Price mentioned Thumbshots, a free tool to compare overlap among the first 100 results between any two major search engines.  I then introduced this site to Shally, shortly after he invited me to join the sourcing team at Microsoft. After a number of resume-specific searches, he found that the overlap was almost always under 20 percent, and sometimes much less.  In other words, the algorithms behind each search engine are different enough, that even when searching with the exact same search string, you will get about 80 results out of 100 from one engine that you won't see when running that search on another engine.

So just as Jim has effectively built on that finding, he has introduced many other related avenues to spur greater understanding of search engines and more productive resume search. I hope we will see others build on Jim's methodology to help validate his findings, as well as take them in new directions.

Thank you for this initiative, Jim.  Anything that takes all the raw data out there and tries to make some sense of it for recruiters is useful and most welcome!  It will be interesting to see how the industry responds to this, to see what form this analysis should take in future years, and what work by other researchers will build off of it.
 

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