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# The (statistical) Truth About Cock Size

Thanks.

Originally Posted by Priapologist
The 300 men in the Ansell LifeStyles condom survey act as a representative sample of the whole male population. The sample size is large enough to do such basic statistics on and those data are backed up by every other clinician-measured survey that I have seen. In fact, the Ansell’s study is actually on the high side of the reported numbers, so my statistical analysis is probably over estimating the average penis size and distribution.

The basic idea behind this process: say that I have a jar containing 10,000 marbles of various colors and I want to know more or less how many of each color I have. I can either count all 10,000, which would be tedious, or I can pull out 50 marbles at random and note the colors obtained and their frequency. This is a sample (50) of a population (10,000). So Ansell pseudo-randomly* noted the erect lengths and girths (analogous to marble color), and how often those data occurred (frequency), of 300 American university students on holiday in Cancun.

Penis sizes, like most natural phenomena, adopt a normal or near-normal distribution, wherein 68% of the sample (and hence the population from which the sample is drawn) will fall within one standard deviation from the mean, or average, value. Likewise, 96% of the sample will fall within two standard deviations, and 99.6% will fall within three standard deviations (SD). Hence, 8.352 inches is three SD from the mean, 9.177 inches is four SD, et cetera. A z-score calculator determines the odds, 1 in x.

That is how 300 drunken frat boys informs the rest of us how long the average penis is.

*I said pseudo-random here because this is a biased sample, both from the design criteria and due to self-selection bias, i.e. guys with bigger penises were probably more willing to get measured than guys with shorter/thinner penises… which further suggests that this analysis is on the high side of the ‘true’ averages.

Pri

fascinating…

So for natural phenomena, 68% is the accepted percentage for the SD? Along with 96% as the limits of the second? Or were you just using those as an example?

I hope I’m understanding this right. It doesn’t sound too complicated, but definitely interesting.

Fascinating..

So for natural phenomena, 68% is the accepted percentage for the SD? Along with 96% as the limits of the second? Or were you just using those as an example?

I hope I’m understanding this right. It doesn’t sound too complicated, but definitely interesting.

It is true for any “normally distributed” data: 68% of the values lie within one SD of the mean, 95% within two SDs, 99.7% within 3 SDs, etc.

That is why one can say with high confidence (ie, you may often hear reference to the 95% confidence level) for normal distributions, which include most natural or biological phenomena, that a value is in the range of y to z, with y being 2 SD’s below the mean, and Z being 2 SD’s above it. There is only a 5% probability that data will be outside of that range.

4/2008 Bpel 6.50, Beg 5.5, Mseg 4.9

6/2008 Bpel 6.75, Beg 5.5, Mseg 5.1

9/2008 Bpel 7.00, Beg 5.5, Mseg 5.1

So the first SD is centered around the mean?

What if there’s discrepancy in the actual size of the SDs? Or is that to be expected?

Its an established branch of maths so all this is not new. There are levels of confidence in the estimations which depends on sample size and other factors.
To estimate millions on a sample of 300 is not as accurate as it could be but I forget the specifics of how accurate or confident the answers could be said to be. Normally each estimate is qualified with a confidence level of 99%, 95%, etc

I wasn’t challenging the math, just wanted to know more so I could use it :) I love learning new stuff like this.

So the first SD is centered around the mean?

What if there’s discrepancy in the actual size of the SDs? Or is that to be expected?

Yes, both of the first SDs are centered around the mean. The mean is actually not a real group of data, nor even one piece of data, but is merely a arithmetically derived value. It just shows you where the distribution is located. The SD shows you HOW it is distributed. There is no significant probability associated with the mean as there is no variation at that value.it’s a point, not a range like that expressed by the SD, which is a raw real value. The SD within a population sample of normally distributed data does not have any size discrepancy. But, yes you would expect it from different samples drawn from the same population or samples from different populations. And there are equations to normalize those.

4/2008 Bpel 6.50, Beg 5.5, Mseg 4.9

6/2008 Bpel 6.75, Beg 5.5, Mseg 5.1

9/2008 Bpel 7.00, Beg 5.5, Mseg 5.1

Originally Posted by panthro
To estimate millions on a sample of 300 is not as accurate as it could be

Actually, as I mentioned a couple pages back, population size (e.g., “millions”) makes no difference vis-a-vis the sample size (e.g., “300”) needed to produce a confidence interval of whatever narrowness you desire. (Unless you’re dealing with samples that are a pretty large proportion of the population — more than, say, 5 or 10% — in which case you can throw in the finite population correction factor.) A sample of greater than 300 would certainly be desirable, but this has nothing to do with the size of the population to which we want to generalize. A bigger concern with this study is the lack of random sampling from the population we care about. But a variety of studies using a variety of sampling methods have turned up similar results.

How do you all feel about the girth numbers? To me, they seem a little high. I’ve gone on LPSG and looked at some of those pictures and regardless of what’s being claimed, there don’t seem to be a lot of real monsters out there in girth. A lot of the people that claim 7” look more like 6” and the ones that claim 6” look like 5.5”, etc.

Originally Posted by Priapologist
And only 30 in the entire country who possess 10 inches or more.

—I don’t believe this. There’s more who just didn’t are to participate with these surveys. I’m not implying that their on this site.

I've been told there a new 'confidence' in my step!!!!

Originally Posted by It-Urts
Originally Posted by Priapologist
And only 30 in the entire country who possess 10 inches or more.

—I don’t believe this. There’s more who just didn’t are to participate with these surveys. I’m not implying that their on this site.

You are SO RIGHT! Those thousands of guys with really fucking huge dicks are HIDING! Ha, ha, ha! Makes perfect sense!

[/sarcasm]

Originally Posted by It-Urts
Originally Posted by Priapologist
And only 30 in the entire country who possess 10 inches or more.

—I don’t believe this. There’s more who just didn’t are to participate with these surveys. I’m not implying that their on this site.

Seriously, yes, the dataset from which this analysis is drawn is flawed, but there are more randomly generated datasets from all over the world, of thousands of men, that yield roughly the same information. Why do some guys want so fucking desperately to believe that GIANT penises are swinging between the legs of every fourth man on the street?

I. DO. NOT. GET. IT.

As I have pointed out, this dataset supports conclusions fairly robustly out to the second standard deviation, plus and minus, about the mean, and that the mean is more of less correct based on the dozen other studies of thousands of men, including our own PE data site. Are the numbers valid at the extremities of the tails, the fourth deviation and beyond? No, probably not, but that was not the point!

Let me say this again: I did this analysis to demonstrate that most men, 96%, fall between ~4.5 inches and ~7.5 inches.

Understand?

The rest is just window dressing and watercooler fodder.

So in the real world with a population of 7 billion, chances are pretty slim that more then a couple 11” cocks could be found at any given time! (More then 50% of the world population is female, and then there are the kids, so maybe 2.4-2.6 billion men in total.)

Originally Posted by Priapologist
An 11 inch penis would be at 6.21 S.D. - effectively over one in one billion (or so).

A 13.5 inch penis would be at 9.24!!! S.D. - effectively… well, if you had an infinite number of penises, one of them might be 13.5 inches.

That is statistically speaking, mind you. :D

Pri

2007-01-27 5.3" BPEL 4.8" EG, Less than 3" Flaccid, and sometimes less than 2"

As of 12-07-2008 7.75" BPEL 7.1" NBPEL 5.7"MSEG 6"+ BSEG. Ultimate goal 8+ inches NBPEL, 8.5" BPEL 6.3" EG (2" diameter just sounds so cool!)

Flaccid 5+ inches on a good day. 4 1/2+ pretty much anytime. My gains have slowed to a snails pace, but I will not quit!!!!!!!

Originally Posted by bigluke39
So in the real world with a population of 7 billion, chances are pretty slim that more then a couple 11” cocks could be found at any given time! (More then 50% of the world population is female, and then there are the kids, so maybe 2.4-2.6 billion men in total.)

Sigh.

Since we are on TP hoping to make ourselves larger, is anyone in the same boat I am? In reality, based on studies, I am considered above average. I am at 7” BPEL x 5.75 EGM to 6.25” EGB, mushroom head of 6.5”. I have married for 15 years and together with my wife for 20 years now. We have a good sex life and it is obvious she orgasms with me several times per session. She was 19 when we met. Prior to us meeting she had sex with 5 guys and gave one other oral sex. One was in the military, in fact she broke up with him to begin seeing him. She was a real a\$\$ and pretty much raped her whenever they had sex (I.e. Holding her down when she said stop, etc.) She said for the others she was usually drunk, sex was never in a real relationship but rather a back room encounter during a party. She says she does not remember much other that it was usually over soon after it started (wham bam thank you mam she calls it). She said that there is no comparison to what I do with her now.

With all this why do I dwell on wondering if there was one or more guys who were larger. Why do I wonder if one of more of them lasted for a long time and gave her the same pleasure or more than I do now. She explains that the mindset back then for her, being of low self-esteem, was that giving sex to the guys that asked, would hopefully lead to a relationship which is what she wanted so much as a teenager.

At 40 yo I am embarrassed to be even thinking like this. Heck I have three kids now with the oldest being 13. I know she remembers really nothing of what happened from that long ago, I know I can’t remember much on my past sex. But I get hung up on how she felt back then when she was actually with them, not that she thinks about it now.

I guess I am just wondering if I am alone if the way I am thinking. It is not fun. Anyone else on TP dwell on stupid crap like this? Thanks for the feedback.

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