Self-selection?

In chapter 7 we introduce the extraneous variable of selection. Self-selection is a form of selection that occurs when people choose to do one thing and not another. A good example is when high school students choose to drop out of school.

An uniformed or naive researcher might draw the wrong conclusion when presented standardized test scores of 9th graders and 10th graders if a large proportion of the students dropped out of school when they turned 16 years of age. Assume that the 16 year olds who dropped out had lower standardized test scores and also assume that the law required them to attend school until they turned 16. In that scenario, the 10th grade AVERAGE scores would rise because the scores of the students who dropped out would no longer be included.

However, if a researcher did not know that the 9th and 10th grades were different to start with because of self-selection, he or she might look for another explanation. Using this example as an introduction, look at this recent news story from the Boston Globe about self-selection by gender in scientific, engineering, and technical fields.

This article examines a controversial area in contemporary culture, the relative imbalance of males over females in scientific, engineering, and technical fields. This imbalance may have many causes. As a recent New York Times article noted, gender discrimination and sexual harassment (both quid pro quo and hostile environment) are much more common in scientific, engineering, and technical fields.

The Boston Globe story, however, highlights the research of an economist, Joshua Rosenbloom of the University of Kansas. He decided to study men and women in the area of information technology. He and his co-authors found that men and women who enjoyed working with tools or machines were the most likely to choose a career in information technology. Also, people who enjoyed working with people turned out to be less likely to choose a career in information technology. His research, with co-authors Ronald A. Ash, Brandon Dupont, and LeAnne Coder was published in the Journal of Economic Psychology. They concluded that self-selection was the main reason for the paucity of women in information technology positions.

Of course, self-selection is not the only factor operating here. The interesting new finding is that self-selection may play a large role than previously imagined in the career choices of men and women. Also mentioned in the Boston Globe article is the research of Susan Pinker. She has found that in societies with the greatest amount of personal freedom, women opt for jobs not typically held by men, thus contributing to the disparity in occupational choice. Paradoxically, the proportions of women working such jobs is highest in countries with lower levels of individual freedom, and yes, in those societies the disparity in the jobs between men and women is less. Here is a link to a New York Times review of her book: The Sexual Paradox: Men, Women, and the Real Gender Gap.

Gender studies are a fertile field for social scientists and present them with many opportunities for conducting research and for teasing out the interactions between multiple sources of causation. However, some of those sources may be due to internal factors such as personal preference.