The Gizmodo blog Throb, a Web site focused on the science of sex, released its own sex education survey (Kelly, 2015). The journalist who developed the survey wrote: “I hope that with enough of your answers, we can start to build a picture of what sexed actually looks like in [the United States]. And then maybe we can start to figure out how it actually affects the students who take it.”

a. Do you think the journalist’s results are likely to be representative of the U.S. population? Why or why not?

b. Describe the people most likely to volunteer for this sample. Why might this group be biased in comparison to the overall U.S. population?

c. The blogger says, “Five minutes poking around online forums where teens ask questions about sex can make me weep with rage and despair,” an indication that she believes that misinformation is common. How might her perspective, likely one reflected in the blog Throb generally, lead to a particular type of survey respondent?

d. Because this survey is posted online, it’s likely to get a large number of respondents. Why is it not enough to have a large sample to conduct a study with high external validity? What would we need to change about this sample to increase external validity?