Kinsey Fact and Fiction
May 4, 2005
by Jennifer Roback Morse, Ph.D.

Both the February PBS documentary about "sex researcher" and the November theatrical movie about the same man ( a bomb, with a bit more than $10 million in revenue) presented fawning portraits. Neither set of film-makers bothered to let ordinary viewers what professionals have known for a long time: Kinsey's findings are hopelessly flawed.

The most definitive debunking of Kinsey's work was done in the dispassionate University of Chicago study by Edward Laumann, John Gagnon, Robert Michael and Stuart Michaels, published in the 1990's. You wouldn't think it a book about sex would be sleep-inducing, but leave it to academics with a big fat research grant-- this study is so dull it can produce academic coma. It is careful in its science, however, and has harsh words about Kinsey's "pioneering" investigations. Kinsey's pool of study subjects, for instance, "failed to meet even the most elementary requirements for drawing a truly representative sample of the population at large." It turns out that the professor drew his interview subjects from groups of people especially likely to have had exotic or deviant sexual experiences. He recruited from prisons and reform schools, including men imprisoned for sex offenses, thus increasing the likelihood of his subjects reporting deviant sexual experiences. He recruited from homosexual friendship and acquaintance networks, thus inflating the estimated percentages of homosexual practice far above any other estimates based on representative sampling techniques.

Kinsey's method of collecting his data was also unusual by social science standards. He did not by ask a fixed set of questions of all the participants in his survey. Instead, Kinsey and a handful of colleagues took a lifetime "sex history" on each subject. They pressed people extensively not only on behavior, but also on fantasy, and also challenged respondents. In a courtroom, this would be called, leading the witness.

Kinsey's estimated percentage of homosexuals in the population is one of the many places where his methods misled. If you asked Americans what percentage of the population is homosexual, the most common answer now would be something around 10%-- which comes from Kinsey. Kinsey claimed that 13% of men and 7% of women are exclusively homosexual. Gay rights advocates averaged these two numbers as part of a campaign to convince the public that "gays people are everywhere."

But Kinsey's sampling and interviewing techniques resulted in a significant overstatement of the extent of homosexuality in the population. No other study using a statistically representative sampling of the whole population has ever come close to replicating Kinsey's percentages. The University of Chicago study found a core group of the population who define themselves as homosexual or bisexual, have same-gender partners and express same-sex desires. The size of this group is a very modest 2.4% for men and 1.3% for women. Nowhere near Kinsey's claims.

Kinsey's message was received enthusiastically by many influential parts of our national elite. (The many bubbling review for the two recent Kinsey films demonstrate that his claims continue to be embraced in important quarters, despite having been demolished as social science.) For this reason, Kinsey's work has had an enormous influence.

But the public deserves to know that his writing (one should hesitate to call it research) is fatally flawed. What a shame that this tendentious and manipulative man set the tone for much of today's understanding of human sexual experience.

Jennifer Roback Morse is a research fellow at the Hoover Institution, and the author of 101 Tips for a Happier Marriage.