Krantz has research to back that up. But as with college students, people on the Internet are skewed toward the high end of the socio-economic and educational spectrums, says Minnesota State University's Linda Jackson, PhD, who recently reviewed the demographics of Internet study participants. But for issues of prejudice, attitudes and the like, we probably need to be more careful. In the end, researchers who use the Web should recognize and report that their samples aren't globally, or even nationally, representative, adds Aspinwall. If researchers want a controlled sample, they should limit who accesses their research site rather than open up a Web-based study to the world, adds University of Maryland psychologist Kent Norman, PhD, a pioneer of Internet research.
Researchers can also gain access to special populations of people through the Internet.
The same study conducted via regular mail would be costly, time-consuming and result in a relatively small sample. But within a few days of sending out his e-mail notes, Birnbaum had several hundred responses. Along with obtaining larger sample sizes through the Web, online research saves money, a major advantage to researchers at small colleges and universities, says Hanover College's Krantz. Not only do researchers save on laboratory space, and printing of study materials, but labor costs are reduced because researchers don't need to hire lab assistants to man their labs or input data. On average, they post a study a week devoted to research on judgment and decision-making.