# Men have on average more sexual partners than women?
**URL:** https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824
**Category:** Factual Questions
**Created:** [January 7, 2001, 6:03am UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824 "2001-01-07T06:03:29Z")
**Posts on this page:** 7
**Page:** 2
### Author:  [@Tzel](https://boards.straightdope.com/u/Tzel)
#### Post date: [January 8, 2001, 11:27am UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/21 "2001-01-08T11:27:26Z")
> [@](#):
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> \*Originally posted by tbea925 \*
> \*\*
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> > [@](#):
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> > \*Originally posted by Tzel \*
> > it doesn’t matter because the average for each gender is the same regardless. \*\*
>
> Sigh.
>
> OK, say you had 100 men and 100 women.
>
> Fifty of the men have had 10 partners.
>
> Fifty of the men have had only one partner.
Clarify. Is this group of 200 people the entire population, or merely a sample? If it’s a sample of a larger group, it’s entirely possible that the averages will be different, for the reasons that have already been pointed out. If this is the entire population, and each person can only have had sex with a member of the opposite sex within the population, then the average for the genders is mathematically guaranteed to be the same. I will prove this below.
> [@](#):
>
> Can it be inferred then that 10 women have had 50 partners? (no) How about presuming that for the women partners of the men who have had only one partner, each woman will have also had only one partner? (no) Can we assume that 40 of the women have had no partner? (no)
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> > [@](#):
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> > These questions are very perplexing, because they make no difference whatsoever in what the average turns out to be. In short, they are pure nonsense.
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> > > [@](#):
> > >
> > > That’s the only way your premise that the average number of partners between the two sets must be the same can succeed; you would have to exclude interactions between the three groups above.
> >
> > This makes no sense. What are the “three groups”?
>
> The function between the two sets is not both one-to-one and onto, so the premise fails. \*\*
It is one-to-one, except for threesomes and such, but even that will not change the fact that the average for each gender must be the same. And what do you mean by “onto”? Your post is too confusing to respond to definitively, so I’ll just prove what I’m saying.
You have a population of 100 men and 100 women.
Suppose one man has sex with all of the women. The average number of partners per woman is 1. The average number of partners per man is also 1. (1 man has had 100 partners, the other 99 have had 0. 100/100 = 1)
Suppose each man has had sex with only one woman, and each woman has had sex with only one man. Again, the average number of partners per person is 1, for both genders.
If we use your example, we can also see that the average will have to be the same for each gender.
50 of the men have had 10 partners each.
50 of the men have had 1 partner each.
The average number of partners per man is equal to ((50 \* 10) + (50 \* 1)) / 100. Or 5.5 partners per person.
So, we have 550 partnerships to account for. No matter how we divide them among the women, there will still have to be 550 partnerships among the women as well, so the average will have to be 5.5 partners per woman.
To look at it from the bottom up, if we have a population of 100 men and 100 women, the average number of partners per person will rise by .01 for each gender whenever there is a new partnership. It doesn’t matter who has sex with whom, the average raises the same amount every time a new pair has sex. This principle holds true for the real world as well, except because of the slight difference in proportion of men and women, the average will rise slightly more for the smaller segment of the population, men. So the average number of partners per man is necessarily larger than the number of partners per woman, but not by a particularly large difference, such as those often found by surveys, which are explainable only by imperfect sampling or lying. In the case of a 49:51 split, the average number of partners per person in the 49% group must necessarily be 98/24900 greater than the 51% group. That’s .000392156%.
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### Author:  [@Tzel](https://boards.straightdope.com/u/Tzel)
#### Post date: [January 8, 2001, 11:29am UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/22 "2001-01-08T11:29:43Z")
Oops, I messed up the quoting in the middle of that post. Damn, really should preview. Well, I think you can figure out which statements are mine. The sentences starting with “These questions” and “This makes” are mine.
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### Author:  [@Sigene](https://boards.straightdope.com/u/Sigene)
#### Post date: [January 8, 2001, 11:43am UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/23 "2001-01-08T11:43:38Z")
The people who have mentioned prostitutes are correct. The original study did not include them. Later studies that include prostitutes show the numbers are more in line.
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### Author:  [@Tzel](https://boards.straightdope.com/u/Tzel)
#### Post date: [January 8, 2001, 12:12pm UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/24 "2001-01-08T12:12:07Z")
Err, the very last figure I made was incorrect. I just rechecked the math, and the actual figure is 4.0816% greater. I think I divided the wrong things.
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### Author:  [@JeffB](https://boards.straightdope.com/u/JeffB)
#### Post date: [January 8, 2001, 1:53pm UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/25 "2001-01-08T13:53:12Z")
**Tzel** , you are correct if you are looking strictly at the **mean**. The **median** or **mode** could both produce different numbers for the “average” number of sexual partners. Let’s take this set of data:
[ul][li]10 men with 10 partners[/li][li]45 men with 5 partners[/li][li]25 men with 2 partners[/li][li]15 men with 1 partner[/li][li]5 men with 0 partners[/ul][/li]
[ul][li]2 women with 50 partners[/li][li]8 women with 10 partners[/li][li]25 women with 5 partners[/li][li]20 women with 2 partners[/li][li]45 women with 1 partner[/ul][/li]
For men: mean = 3.9; median = 5; mode = 5. For women: mean = 3.9; median = 2; mode = 1. With this data set, the typical man (not average) has more partners.
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### Author:  [@john\_e\_wagner](https://boards.straightdope.com/u/john_e_wagner)
#### Post date: [January 8, 2001, 2:04pm UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/26 "2001-01-08T14:04:33Z")
On a somewhat related topic I remeber reading that senior citizens are having a problem with AIDs due to men having multiple partners. It seems that older men (being a relatively rare commodity) are able to have, multiple sexual partners (harems if IIRC). Combine this with the fact that senior women fell that since they are past menopause that they do not need protection.
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### Author:  [@Cartooniverse](https://boards.straightdope.com/u/Cartooniverse)
#### Post date: [January 8, 2001, 3:32pm UTC](https://boards.straightdope.com/t/men-have-on-average-more-sexual-partners-than-women/48824/27 "2001-01-08T15:32:34Z")
> [@](#):
>
> \*Originally posted by Lynn Bodoni \*
> \*\*
>
> > [@](#):
> >
> > How is it possible in all surveys on sexual behavior that men have, on average, more sexual partners than women? Who else are they sleeping with to raise the average?
>
> Other men, sheep, dolphins, the whole barnyard and beyond. Not to mention inflatable women and animals, and stuffed plush objects. I kid you not. \*\*
Oye gevalt ;j You kid me not? \ I read the Hite Report when I was 14- didn’t see BUPKUS on dolphins. Of course, that was the Hite Report On FEMALE Sexuality. Are you insinuating that it’s the men who have a prediliction for…er…alternate methods? Gasp… 😃
Cartooniverse
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