Question: How does conducting research on the Internet impact the ways that researchers must deal with human subjects?
As with anything else that the Internet has touched, it has fundamentally altered research with human subjects via the Internet. In some ways this has opened up new opportunities, both in the availability of research subjects and in research design. It can also cause a few problems. Some of the opportunities are for researchers to be able to inexpensively contact a large number of people, for researchers to be able to reach subjects outside of their local community, and for researchers to see how subjects behave while on the Internet and how this may be different than their behavior in the "real world." The problems it may cause are just as prevalent.
Researchers need to decide whether or not an item posted on the Internet constitutes a "public" document and can therefore be used for research. This is a tricky subject because not everything posted on the Internet is meant to be seen by everyone, but at least most posters know that it may be possible for the document to be seen by a large number of people. Unless a document is posted on a password-protected website, I can't really see how the author can expect that it couldn't be studied and used for social or behavioral research. Furthermore researchers must document these findings anonymously, so even should someone post something embarrassing on the Internet and not want it to be further dissected by a researcher, at least their name will be left out of the paper.
Another possible problem is that it is difficult to tell if a subject is old enough and has the mental capacity to be participating in the research effectively. Not only could this give the researcher incorrect results, but it bring the researcher a host of other problems, calling in to question their research design. Furthermore it is more difficult to tell if a subject is simply lying about their gender, age, or any other information that may be relevant to the test. This of course could be a problem in traditional research designs as well.
Using the Internet as a research tool can be very powerful as it allows researchers to perform research on larger groups of people, and can find subjects outside of their area. However it can introduce more variables and other problems into the research. It must be planned and implemented carefully.