These web site usability references are used throughout our Web Site Usability Workshops . They compared the various sites and extracted usability principles based on these tests. Unfortunately the details of the methodology used is not available.
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A web specific look at Nielsen s 20 Heuristics. The overriding theme for applying these heuristics to the Web is to use links effectively. You can't get to Web heaven if nobody will visit your site. I want you to succeed. Web pages designed using the guidelines were usability tested.