How many sexual partners have you had? If this were an actual survey, would you lie about it? The discussion often comes up during the beginning stages of dating, and apparently a lot of people are lying about their numbers.

When it comes to opposite-sex partners, the numbers in research aren’t adding up. Mathematicians say the average count for each gender should be the same, yet most surveys out of countries like the U.S. and the U.K. find men are reporting two to four times as many sex partners as women do!

So are men fibbing to embellish their sex reputations? Or are women stretching a little more than the truth when it comes to their sexual history?

After all, evolutionary argument argues that men are supposed to be promiscuous. That’s what allows them to spread their seed in their effort to guarantee the success of the human race. Women, on the other hand, need to take care of the offspring with those few suckers — I mean, fine gents — who are willing to stick around and help out.

Still, statisticians are sounding the bell that it is impossible and incorrect for survey results to show heterosexual males as having more partners on average than heterosexual females.

So where are all those extra partners for the males coming from — or, in the female's case, disappearing to?

— Men are either pigs or just plain lucky.

While unfair social notions want to chalk men up as pigs on this matter, researchers warn that male sexual antics do not explain the great gender divide in sexual histories. They further discourage any idea that there are a bunch of “lucky Joes” chasing after the same women.

While investigators will often point to prostitutes, who are not included in such surveys, as one possible reason for the difference in numbers, a society having a few busy ladies does not support the math involved. The idea that men are getting busy at popular destination spots in other countries further doesn’t support such.

— Men are exaggerating.

And quite innocently at that. A 2005 study conducted by psychology professor Dr. Norman Brown found that men tend to overestimate the number of sexual partners they’ve had. They misrepresent themselves in simply using a rough approximation method. Women, on the other hand, are likelier to actually stop and think about individual sexual incidences to figure out their own tally. In general, women know exactly how many men they’ve been with, and can typically name names. However, the approximation strategy men use is known to result in overestimation. Brown’s study, by the way, found that the average number of sexual partners for U.S. heterosexuals, mostly in their late 40s, was 8.6 for women and 31.9 for men.

— Men have imaginary friends.

While dream girls shouldn’t count, in his memory they often do.

— Studies aren’t defining terms.

If we want to give men the benefit of the doubt for a second, we should acknowledge the fact that many research studies don’t explicitly state what they mean by “sex” or “sexual partner.” Do they mean oral sex? Hooking up (not that that vague term provides any clarification)? Same-sex interactions? Hmmm...Men very well could be taking all of those into consideration and we just don’t know it.

— Women, conveniently enough, “forget.”

To further take the heat off the men, let’s not overlook her mental lapses in recall. Hers, however, are probably more intentional. This is most ironic given the aforementioned research finding on name recall. Thanks to the double standard issue of women being “sluts” — instead of “studs” like men when it comes to sleeping around — counting up her total to date is a very sensitive matter. Suddenly, Tommy, Pete, and/or Bob are non-existent. This is because one number can make all the difference in whether she is regarded as a “whore.”

Even the most sexually liberated gals will edit their numbers. For example, she might leave Tommy off since he was a one-night stand. And, maybe Bob is off the list since he couldn’t last for more than a minute.

Some women will also simply admit that the “what happened in Vegas, stays in Vegas” applies when it comes to her selective memory. Amusingly enough, that often includes her time at college.

— People are simply lying.

A fascinating aspect of this numbers research is that many people will lie about their count, and then admit to lying or inaccuracy. In Brown’s study, 21 percent of men and 15 percent of women admitted to fudging their digits. These self-incriminators were also more likely to use rough estimation than other respondents.

I don’t know about you, but when it comes to the numbers game, I’m thinking that, by and large, nobody’s number can be trusted.

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In the Know Sex News . . .

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Multiple Factors Determine Sexual Orientation. A new study on twins, conducted by Swedish and British researchers, gives reason to believe that sexual orientation is due to pre- and post-natal factors. Results revealed there is no single 'gay gene' or one environmental variable that determines non-heterosexuality. Rather, it was determined that heterosexual behaviors are influenced by a mixture of genetic and environmental factors.

Sexual Infections Doubling Among Middle-Aged Brits. Researchers from Britain's Health Protection Agency are reporting that sexually transmitted infections have more than doubled in less than a decade for those over the age of 45. Men ages 55 to 59 were most likely to have an STI, while rates were highest among women ages 45 to 54. Meeting casual partners online may be one reason why.

Dr. Yvonne Kristín Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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