Avoiding Bias from the Survivor Effect

Only a few of the survey sites we analyzed in 2000 are still around. We can safely assume that the surviving sites are not a random sample of the original group, but rather that significant differences exist between the sites that made it and those that died. Survival might be due partly to luck, but it is mainly a result of good management and an understanding of Internet fundamentals. Thus, the surviving sites are likely to be disproportionately clued-in about what it takes to run an online business.

Nielsen, Jakob. Alertbox (2002). Articles>Usability>Methods>Web Design

Evaluation of an Informational Web Site: Three Variants of the Think-aloud Method Compared    

To evaluate Web sites, usability experts often use methods that were originally employed for the evaluation of software applications. In doing so, they assume that these methods will work exactly the same for both types of test objects. However, there is a major difference between transactional software applications and informational Web sites, a difference that could have an effect on the workings of various usability methods. As such, we felt that it was valuable to repeat one of our previous studies in which we compared concurrent think-aloud protocols, retrospective think-aloud protocols, and constructive interaction to evaluate a Web application, this time using a Web site. The results of our study showed that in some respects, the methods did work differently depending on the test object they were applied to. However, we conclude that the three methods are largely interchangeable and that the decision to choose one variant of the think-aloud method over the other should be based on practical considerations.

van den Haak, Maaike J., Menno de Jong, D.T. and Peter JanSchellens. Technical Communication Online (2007). Articles>Web Design>Usability>Methods

User-Testing Techniques - Site Reviews

Accurately measuring reader-friendliness is a complex task for any Website. Usability testing techniques have been applied with some success to Web pages. But formal usability tests are difficult to set up, and very expensive to conduct (often prohibitively so). And the diversity of the audience of Internet sites probably limits the utility of formal usability testing of many Web pages. Happily, inspection-based usability evaluation is generally as effective as formal, experimental testing, and it is much easier (and less costly) to conduct. This series focuses on inspection-based usability assessment. A site review is basically an unstructured inspection by a third party, typically focusing on the site's usability and aesthetics. It's a difficult but worthwhile effort for serious-minded authors to seek out reviewers who are willing to invest the time to undertake a serious review of your site, offering constructive suggestions for improvement.

Sullivan, Terry. All Things Web (1996). Articles>Usability>Methods>Web Design