What percentage of the population considers themselves gay? This number has always been hard to pin down: sexuality is fluid, and plenty of people still feel pressured to hide their sexual orientation. But a new study has tried, and come up with a number that’s higher than most.

According to a study from the National Bureau of Economic Research, about 20 percent of the population is attracted to their own gender. That’s nearly double the usual estimates of about 10 percent. The authors explain that their methodology might have something to do with it:

Participants were randomly assigned to either a “best practices method” that was computer-based and provides privacy and anonymity, or to a “veiled elicitation method” that further conceals individual responses. Answers in the veiled method preclude inference about any particular individual, but can be used to accurately estimate statistics about the population. Comparing the two methods shows sexuality-related questions receive biased responses even under current best practices, and, for many questions, the bias is substantial. The veiled method increased self-reports of non-heterosexual identity by 65% (p<0.05) and same-sex sexual experiences by 59% (p<0.01). The veiled method also increased the rates of anti-gay sentiment. Respondents were 67% more likely to express disapproval of an openly gay manager at work (p<0.01) and 71% more likely to say it is okay to discriminate against lesbian, gay, or bisexual individuals (p<0.01).

Essentially, using a veiled question rather than a direct one uncovered a whole group of people who would not directly say they weren’t heterosexual. This kind of veiled questioning can get at all sorts of answers that people don’t want to give, like the incidence of rape. Daniel Luzer at Pacific Standard explains that uncovering these hidden biases is really important for understanding how accurate these kinds of surveys actually are:

The most important takeaway isn’t a final tally of the gay people in society, but, rather, an understanding of the ways in which surveys and other existing attempts to measure such things might be slightly misleading. “The results show non-heterosexuality and anti-gay sentiment are substantially underestimated in existing surveys, and the privacy afforded by current best practices is not always sufficient to eliminate bias,” note the researchers, who were just looking at the way surveys might under-count both homosexuality and attitudes toward homosexuality.

There may never be a time when people will accurately answer surveys, but at least survey givers are getting better at tricking us into being honest.

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