http://en.wikipedia.org/wiki/Kinsey_Reports#FindingsThere was further analysis done after their initial publication, if you read the last paragraph it talks about how even after they removed the stats taken from prison populations etc, it affected the overall results very little.
The reports also state that nearly 46% of the male subjects had "reacted" sexually to persons of both sexes in the course of their adult lives, and 37% had at least one homosexual experience.[7] 11.6% of white males (ages 20–35) were given a rating of 3 (about equal heterosexual and homosexual experience/response) throughout their adult lives.[8] The study also reported that 10% of American males surveyed were "more or less exclusively homosexual for at least three years between the ages of 16 and 55" (in the 5 to 6 range).[9]
7% of single females (ages 20–35) and 4% of previously married females (ages 20–35) were given a rating of 3 (about equal heterosexual and homosexual experience/response) on Kinsey Heterosexual-Homosexual Rating Scale for this period of their lives.[10] 2 to 6% of females, aged 20–35, were more or less exclusively homosexual in experience/response,[11] and 1 to 3% of unmarried females aged 20–35 were exclusively homosexual in experience/response.[12]
Academic criticisms were made pertaining to sample selection and sample bias in the reports' methodology. Two main problems cited were that significant portions of the samples come from prison populations and male prostitutes, and that people who volunteer to be interviewed about taboo subject are likely to suffer from the problem of self-selection. Both undermine the usefulness of the sample in terms of determining the tendencies of the overall population. In 1948, the same year as the original publication, a committee of the American Statistical Association, including notable statisticians such as John Tukey, condemned the sampling procedure. Tukey was perhaps the most vocal critic, saying, "A random selection of three people would have been better than a group of 300 chosen by Mr. Kinsey."[13][14] Criticism principally revolved around the over-representation of some groups in the sample: 25% were, or had been, prison inmates, and 5% were male prostitutes.[citation needed] Psychologist Abraham Maslow asserted that Kinsey did not consider "volunteer bias". The data represented only those volunteering to participate in discussion of taboo topics. Most Americans were reluctant to discuss the intimate details of their sex lives even with their spouses and close friends. Before the publication of Kinsey's reports, Maslow tested Kinsey's volunteers for bias. He concluded that Kinsey's sample was unrepresentative of the general population.[15]
In response, Paul Gebhard, Kinsey's successor as director of the Kinsey Institute for Sex Research, cleaned the Kinsey data of purported contaminants, removing, for example, all material derived from prison populations in the basic sample. In 1979, Gebhard (with Alan B. Johnson) published The Kinsey Data: Marginal Tabulations of the 1938–1963 Interviews Conducted by the Institute for Sex Research. Their conclusion, to Gebhard's surprise he claimed, was that none of Kinsey's original estimates were significantly affected by this bias: that is, prison population, male prostitutes, and those who willingly participated in discussion of previously taboo sexual topics had the same statistical tendency as the general population. The results were summarized by historian, playwright, and gay-rights activist Martin Duberman, "Instead of Kinsey's 37% (men who had at least one homosexual experience), Gebhard and Johnson came up with 36.4%; the 10% figure (men who were "more or less exclusively homosexual for at least three years between the ages of 16 and 55"), with prison inmates excluded, came to 9.9% for white, college-educated males and 12.7% for those with less education.[6]
