If you know which sexual orientation people identify with, how much does that tell you about whether they have sex with women, men, or both? How similar or different are the links between identity and behavior for women and men? Detailed tables, along with how we generated our measures, are in the Appendix at the end of this post. Here we focus on a few specific questions:. How common is it for heterosexual men and women to have sex with same-sex sexual partners?
Sexual orientation versus behavior—different for men and women?
As bisexual individuals in the United States U. Previous studies of individual and social attitudes toward bisexual men and women have been conducted almost exclusively with convenience samples, with limited generalizability to the broader U. Our study provides an assessment of attitudes toward bisexual men and women among a nationally representative probability sample of heterosexual, gay, lesbian, and other-identified adults in the U. We included two modified 5-item versions of the Bisexualities : Indiana Attitudes Scale BIAS , validated sub-scales that were developed to measure attitudes toward bisexual men and women.
Bisexuality is romantic attraction, sexual attraction , or sexual behavior toward both males and females,    or to more than one sex or gender. The term bisexuality is mainly used in the context of human attraction to denote romantic or sexual feelings toward both men and women,    and the concept is one of the three main classifications of sexual orientation along with heterosexuality and homosexuality , all of which exist on the heterosexual—homosexual continuum. A bisexual identity does not necessarily equate to equal sexual attraction to both sexes; commonly, people who have a distinct but not exclusive sexual preference for one sex over the other also identify themselves as bisexual. Scientists do not know the exact cause of sexual orientation, but they theorize that it is caused by a complex interplay of genetic , hormonal , and environmental influences ,    and do not view it as a choice.