Equipment Size: What is average?

Normal Curves - Episode 9 Social Desirability
[Regina] (0:00 - 0:08)
There was one study where they recruited men during spring break from a nightclub in Cancun, Mexico called Daddy Rock.

[Kristin] (0:09 - 0:40)
Well, that is not a representative sample, clearly.

Welcome to Normal Curves. This is a podcast for anyone who wants to learn about scientific studies and the statistics behind them.

It's like a journal club, except we pick topics that are fun, relevant, and sometimes a little spicy. We evaluate the evidence, and we also give you the tools that you need to evaluate scientific studies on your own. I'm Kristin Sainani.

I'm a professor at Stanford University.

[Regina] (0:40 - 0:46)
And I'm Regina Nuzzo. I'm a professor at Gallaudet University and part-time lecturer at Stanford.

[Kristin] (0:46 - 0:51)
We are not medical doctors. We are PhDs, so nothing in this podcast should be construed as medical advice.

[Regina] (0:52 - 1:01)
Also, this podcast is separate from our day jobs at Stanford and Gallaudet University. All right, Kristin, today we are going to talk about penises.

[Kristin] (1:02 - 1:07)
Okay, that sounds interesting. But, Regina, is this episode going to be R-rated?

[Regina] (1:08 - 1:45)
I would call it PG-13. You would be able to find all of this in a medical article online. And, Kristin, I also want to point out that although this episode is about penises, it's not really about penises.

Every single thing we're talking about today has a direct analog to other studies, nutrition studies, whatever. So, we are going to cover real stats in epidemiology. It's just that we're using the lens of penises because penises are fun.

And how about I occasionally refer to them as, like, spongy urethra tubes?

[Kristin] (1:46 - 1:49)
That's going to make me blush less, yeah. So, maybe we throw that in sometimes.

[Regina] (1:49 - 2:16)
So, what are we going to do with these spongy tubes? We are going to investigate this question. What is the average erect penis length in the general population?

And yes, it's a very nerdy, very statsy question. I'm going to kick this off, Kristin, by asking you, what do you think the average erect penis length in the population is?

[Kristin]
Like, in the general population of the U.S.?

[Regina]
Yep.

[Kristin] (2:16 - 2:33)
Regina, I have literally never once thought about this in my life. We did talk in an earlier episode about the distribution of flaccid penis lengths. We talked about the Italian stallions in the vitamin D episode.

So, I can tell you some stats on that, but I have no idea.

[Regina] (2:33 - 2:48)
Kristin, I will offer you this. Which Starbucks coffee cup height do you think corresponds to the average penis size? So, you've got short, tall, grande, venti, trenta, with the lid.

[Kristin] (2:48 - 2:57)
Oh, I love that, Regina, because that gives me a benchmark that I can actually visualize, because I have Starbucks coffee a lot. I think it's about a grande. Am I in the ballpark?

[Regina] (2:58 - 3:20)
They're all really reasonable metrics, actually, which is what I think makes it such a good unit of measure and, by the way, really good for our girl talk. So, if I say my last boyfriend was tall and he was awesome, but the new guy is a definite venti, then you will know I'm not just talking about what coffee he drinks.

[Kristin] (3:21 - 3:24)
I am never going to be able to look at my coffee cup the same way again, Regina.

[Regina] (3:25 - 4:20)
You're welcome. So, the reason I am asking this nerdy question, I read a fascinating study, 2014, where they asked a bunch of straight men and women that very question. And men's average guess, 6.2 inches. Women's average guess, 5.3 inches.

[Kristin]
Oh, interesting. Different.

[Regina]
And they're very different. The neat thing is that it kind of corresponds to the Starbucks sizes, actually. We'll do the numbers later, but let's just say men guessed about a grande and women guessed about a tall.

Oh, interesting. So, Krista and I propose for today's episode, we explore the research behind this question and decide who is closer to the truth, men with their estimate of a grande coffee at 6.2 inches, or women with their tall coffee at 5.3 inches.

[Kristin] (4:20 - 4:28)
Oh, I like that, Regina. So, we're going to pit the men against the women and see who got it right. Burning question that everybody wants to know: Who's right?

[Regina] (4:30 - 4:39)
The suspense. One theme of the episode that I hope we bring out today, problems with getting accurate information from people, not just penis studies, all studies.

[Kristin] (4:39 - 4:50)
So many things in science that we measure are really hard to measure. Like if you ask people, how much broccoli did you eat last year? One, they're probably not good at estimating that.

And two, they might, let's say, fudge or exaggerate or round up.

[Regina] (4:51 - 4:58)
Second theme, you don't always need fancy stats. Just getting descriptive statistics of a population is really useful.

[Kristin] (4:58 - 5:12)
I love this theme, Regina. Descriptive statistics are so important. Understanding the distribution of a variable like broccoli eating, really important for public health.

And also just because human nature, people like to know, how do I stack up?

[Regina] (5:12 - 5:32)
Yes. And I want to give you a sneak peek of some of the stats concepts that we are going to see today so you can be on the lookout for them. A bunch of systematic biases and surveys, including social desirability bias and selection bias. And our favorite descriptive stats, mean, median, percentiles, interquartile range.

[Kristin] (5:33 - 5:43)
Regina, I love how we are teaching stats, but we're working in something that will get people's attention. And yes, it is a shameless, straightforward attempt to grab people's attention and we're not afraid to admit it.

[Regina] (5:44 - 6:11)
We will remember it better if it's penises than broccoli. Come on.

[Kristin]
Absolutely.

This is how you get people to remember what the interquartile range is, of course.

[Regina]
It is true. We have no shame about this.

I do want to emphasize, though, it's not just for penis jokes because...

[Kristin]
Really?

[Regina]
Penis size, yes.

Penis size is an important area all on its own. I really think so, believe it or not, in a non-salacious way. Medically important, Regina?

[Kristin] (6:11 - 6:20)
Really? I mean, maybe we should be prioritizing, like, cancer over penis size. You're going to have to convince me that this is an important topic medically.

[Regina] (6:21 - 6:46)
Here's one thing. Somehow, the spongy urethra tube length has become acquainted, for some people, with masculinity and sexual competence. And research has shown that some men, when they think they don't measure up, like literally do not measure up, when they think that they are smaller than average, they avoid sex and intimacy or get seriously depressed.

Or I even read about suicide attempts.

[Kristin] (6:46 - 6:47)
Oh, wow. So that is serious.

[Regina] (6:47 - 6:59)
It is. Or they turn to, you know, weird treatments to make their penis bigger. Like, for example, there is one where you hang weights off the end of your penis every day to try to make it longer.

[Kristin] (7:00 - 7:03)
That sounds totally awful and totally ineffective, Regina.

[Regina] (7:03 - 7:17)
It's because of all this distress that I think it's important for us to know what's normal, so doctors can sit down and have an honest conversation with these men that are coming in and reassure them, maybe.

[Kristin] (7:17 - 8:15)
Maybe some of the men coming in really aren't on the lower end of the distribution. And if they know that, maybe they won't turn to treatments they don't need.

[Regina]
Absolutely.

[Kristin]
All right. But, Regina, going back to those average guesses they found in the study, you said the women guessed 5.3 inches, the men 6.2 inches. The reason you end up with that very precise value with the decimal place is just because if a bunch of women say 5 and some say 6 and some say 4, when you average them together, you end up with a decimal place, just to point that out to people.

[Regina]
Exactly. Yes, good point.

[Kristin]
We're pitting the men against the women, and I'm not sure who would get this more correct, actually.

It's an interesting philosophical question. You know, I don't know who would be better at this guessing game. In favor of women, maybe women see more of these, right?

They may have a bigger sample. But on the other hand, they're probably not getting a tape measure out in the middle at a certain moment, right? So, you know, you'd think the men would have a better sense just because they're more intimately familiar with their own parts.

[Regina] (8:16 - 8:27)
It is an interesting question. Now, straight men might need to extrapolate from their own single part, though, in N of 1 study. Because in that study, they were all straight.

[Kristin] (8:27 - 8:28)
Yeah. Not a great sample, then.

[Regina] (8:28 - 8:35)
Mm-hmm. But that also leads us now to the discussion of pornography consumption.

[Kristin] (8:36 - 8:43)
Oh, good point. Because if they're seeing a lot of examples through pornography, it's not exactly a representative sample.

[Regina] (8:43 - 8:51)
They did a study, the top third. They think that men in porn films are top third in terms of length.

[Kristin] (8:51 - 9:09)
So, if men are watching a lot of pornography, they might be overestimating then. Interesting. I had no idea there were studies on all of this, by the way, Regina.

Fascinating. In contrast, women would presumably be getting a somewhat more representative sample, because it's going to be a little bit more random what they're seeing.

[Regina] (9:10 - 9:13)
So, now I feel like we're back to saying women might be closer to the truth.

[Kristin] (9:13 - 9:22)
I'm going back and forth on this one. I can see it both ways. Yeah, I'm torn.

This is a good contest, Regina. You set up a good question that everybody's going to have to listen to the end, because they want to know who won, the men or the women.

[Regina] (9:23 - 9:24)
Suspense.

[Kristin] (9:24 - 9:32)
Regina, at the end of the day, to know whether the men or women did better, we need some ground truth, right? There's got to be some actual hard data. Hard data.

There is hard...

[Regina] (9:35 - 9:45)
There's very hard data. All right. The first one by someone whose name you've probably heard of, Alfred Kinsey.

[Kristin] (9:46 - 9:53)
Oh, yeah, of course. He was the guy who did a lot of studies on sex, and I remember he had a movie. There was a movie out about him recently.

I never saw it.

[Regina] (9:53 - 10:13)
Yeah, he was one of the first. Started collecting data in 1938, and it is a good movie. Liam Neeson plays Kinsey, and he's kind of hunky.

[Kristin]
Oh, he is hunky, yeah.

[Regina]
I like Liam. It's an interesting story how he got started, though they talk about it in the movie.

Did you know that he was studying wasps before he switched over to sex? Kinsey, yes.

[Kristin] (10:13 - 10:18)
No, I did not know that.

So, how did he get from wasps to sexual behavior?

[Regina] (10:19 - 10:42)
It's not a natural path, I would have to say. It's kind of a wholesome story, though. I love it.

He was a bio professor at Indiana University, and in 1938, there was a group of women, the Association of Women Students, and they petitioned the university because they wanted a course for students who were engaged or married, a bio course.

[Kristin] (10:43 - 10:55)
Oh, that's interesting. Of course, we're talking 1938. People didn't talk very much about sex, so I'm sure both women and men going into marriage probably didn't know a lot, and they went and asked for information.

I love it.

[Regina] (10:56 - 11:15)
I know. So, they gave it to Kinsey. It was a team-taught course, but apparently Kinsey's lectures in particular were a big hit.

They were illustrated lectures, first of all, on the techniques of contraception, the biology of sexual stimulation, and the mechanics of intercourse.

[Kristin] (11:16 - 11:27)
Well, I mean, that's all super important to know, and I'm sure that at the time, a lot of women, probably a lot of men, too, might have been pretty clueless about all this. So, that was really progressive back in 1938.

[Regina] (11:28 - 11:38)
Right. So, students kept coming up to Kinsey, men and women, bringing their sex questions and their sex problems to him, and he kind of morphed it into research.

[Kristin] (11:38 - 11:50)
Oh, interesting. Well, he was probably the only person that they felt comfortable talking about this with, and so they went to him and asked a bunch of questions, and he didn't know the answer, so he went and researched it. Wow, that's an interesting way to find a research question.

[Regina] (11:50 - 12:11)
All of a sudden, wasps are no longer quite so fascinating as they were before. Imagine that. Yeah, so he started researching this in a traditional, rigorous way.

He did interviews, and he coded the data, and kept it anonymous, and he made it into an official field of study. Kind of amazing.

[Kristin] (12:12 - 12:30)
Oh, so he interviewed people about things like their sexual habits. He got data on this, and I'm sure this is probably the first data of its kind that we had. He did like 18,000 interviews in his career.

And what kinds of questions was he asking, Regina? I'm assuming penis length was in there, but what else?

[Regina] (12:31 - 12:49)
Oh, like good stuff. PG-13 here. So, how much sex education did you get as a kid from your parents?

When did you lose your virginity? How often have you had sexual intercourse with your partner? Have you ever cheated on your partner?

What kind of kissing did you do before you were married?

[Kristin] (12:50 - 13:12)
Interesting. So, I get why you think this might be an important area of study, Regina. It's not totally frivolous, because sex is important to people's lives, and they want to understand what's normal, and feel comfortable in their own skin, and have education about what to expect.

Yeah, that all makes sense. I applaud that. So, you mentioned that Kinsey did get penis size measurements.

So, did he just ask them to estimate, or did he actually have them like measure themselves?

[Regina] (13:13 - 14:06)
He had them measure themselves.

[Kristin]
Oh, okay. Well, that's good.

[Regina]
But at home, not in the lab. The interviews were in person, but then some men were sent home with a pre-addressed stamped envelope, blank card, and it was like, get out your yardstick, guys. They had to measure their erect penis from the belly to the tip, and to the nearest quarter of an inch, and send that back in.

[Kristin]
Wow, that's great. So, then did he publish the data?

[Regina]
Sadly, it doesn't look like he published the penis data before he died.

He died in the 50s, but his colleagues organized everything after his death, and they did publish it in this giant book in 1979 with all the tabulations. And I got an original physical edition. It is gorgeous.

It's like typewritten, and it has that vintage feel. I love it. It has all the data.

[Kristin] (14:06 - 14:12)
You got a copy. Wow, nice. And it has like mean, median, interquartile range, all the summary statistics.

[Regina] (14:13 - 14:31)
Even better, they gave it as an actual frequency distribution. Like for the penis length, they have, okay, how many men said 3.0 inches? How many said 3.25?

[Kristin]
So, you have all the data then.

[Regina]
All the data. I put it in a spreadsheet, started to analyze it.

[Kristin]
Wow, did you analyze it for class?

[Regina]
Just for this episode.

[Kristin] (14:32 - 14:43)
Wow, I feel so important, Regina. You did this just for our podcast, and we are probably breaking news then. Is this the first time the penis data have been reported ever?

[Regina] (14:46 - 14:48)
Probably the first time in a podcast. How about in the show notes, I link to my spreadsheet?

[Kristin] (14:48 - 14:56)
You're going to provide the data set. I love this. This is like open science in the middle of a podcast.

Are you providing code as well to analyze it, R code?

[Regina] (14:57 - 14:59)
Well, now I feel obligated.

[Kristin] (14:59 - 15:10)
I think you should provide open data and R code. How many men are we talking about? How big was the data set?

2,500 men.

[Kristin]
And did you analyze all the variables or just the penis length data?

[Regina] (15:10 - 15:16)
You know, I was really tempted to go in and start analyzing everything, but then I'm like, no, Regina, focus. Focus on the penises.

[Kristin] (15:17 - 15:19)
What did you find?

[Regina] (15:19 - 15:34)
Kristin, I am going to give you the answers as a little statistical quiz.

[Kristin]
Oh, I love quizzes.

[Regina]
I know you do.

Okay, number one, the mode was 6 inches. 24% of men put down 6 inches. Exactly.

Interpret that for us.

[Kristin] (15:35 - 16:00)
All right. So the mode is the most common number that the men reported. So if you can imagine this in like a bar chart, the highest bar is going to be at 6.0 inches. It makes a lot of sense to me, actually, because if you're estimating, you tend to round. And I'm guessing that some men just rounded to the nearest half foot, like they were told to round to the nearest quarter inch. But that's really precise.

So probably just a lot of them rounded to the nearest half foot.

[Regina] (16:01 - 16:04)
It's also maybe hard to see. Maybe they were doing this in the dark.

[Kristin] (16:06 - 16:09)
Right. Logistics of this might be a little tricky. Yeah.

[Regina] (16:10 - 16:24)
Not easy, not fun, not sexy. Let's just say that. Okay, correct.

Number one. Number two, 30% of men said less than 6 inches. And what is the median erect penis length in this sample?

[Kristin] (16:24 - 16:45)
Oh, I love that question. I'm going to steal that for like my next midterm for my stats course, Regina. All right, because you told me 30% less than 6 inches and 24% exactly 6 inches.

So that gets me up to 54% of the men. And the median is the point at which 50% of men are bigger and 50% of men are lower. So I know that's going to fall at 6.0 inches.

[Regina] (16:46 - 17:04)
Very nice. That was a very good description. I think I'm going to give you bonus points for explaining your reasoning there.

Okay, one last one. And then you get your A+. The mean was 6.2 inches, which by the way, yes, is exactly the same as the guess in that 2014 study.

[Kristin] (17:05 - 17:06)
Oh, uh-oh.

[Regina] (17:06 - 17:16)
I know. I know. Coincidence, I think.

6.2 inches was the mean. What is the likely shape of the distribution of penis lengths in Kinsey's sample?

[Kristin] (17:16 - 18:00)
Oh, another great question. I'm still for my midterm because if the mean is 6.2, but the median is 6, that means the mean is slightly to the right of the median. And that's what you expect when you have a right skewed distribution.

That means we have a right tail, which means there's a few men with very extreme, long, indirect penises. Those extreme values out in the right tail, they pull the mean to the right because in order to calculate an average, you have to add them into the rest of the values, right? And they're big, so they're going to pull the mean to the right.

The median, on the other hand, is not affected by the extreme values because it's just 50% of men are bigger, 50% of men are smaller. The median doesn't care how big the big men are, right?

[Regina] (18:02 - 18:34)
This is perfect. A++. This is why penis length, I think, is perfect.

It is serious statistics, what we just covered. It just happens to be sexy, silly science at the same time. So, I promise we will get back to our Starbucks coffee cup units.

And I just want to put them in here. Tall coffee cup with the lid is about 5.3 inches. A grande is 6.3 inches. So, the average Kinsey man was just a tiny bit smaller than a grande coffee.

[Kristin] (18:34 - 18:36)
Oh, so this is making me think that maybe the men were right.

[Regina] (18:37 - 19:07)
Mm-hmm. I want to point out, it's not just Kinsey. There have been a lot of other similar self-report studies since then, mostly in the 90s and early 2000s.

I'm not sure why there was a big gap before people rediscovered penises. But the other studies, they found similar results. We had one in 1995.

The mean was 6.3 inches. In 1996, they had one with 6.5 inches as the mean, 6.2, 6.0. They're all high.

[Kristin] (19:08 - 19:16)
These are all studies where the men actually measured. They're not just guessing.

[Regina]
Yep.

[Kristin]
Well, they're all pretty similar to Kinsey. So, again, definitely looks like the men are winning.

[Regina] (19:17 - 19:36)
I know. These were all in the comfort of their own home. But even better, some of the studies didn't even have the men use a ruler.

The men were just sent home with like a paper tape measure without any numbers on it. And then they had to like stick it on their penis and then mark the length and send that back in.

[Kristin] (19:36 - 19:48)
Oh, that's super clever. Because then they can't see the number. So they have no temptation to exaggerate.

They just mark the tape. Great. I guess you could mark the tape higher than you should.

But at least you're not tempted to round up.

[Regina] (19:48 - 19:52)
Right. At least there's no anchoring effect of that like 6.0 inches.

[Kristin] (19:52 - 19:59)
And those studies were coming out closer to the men's guess of 6.2 inches. So I'm starting to get swayed to the maybe the men are going to win this contest.

[Regina] (20:00 - 20:06)
Don't give up on the women yet. Because there are a lot of problems with these studies. I think we need to talk about them.

[Kristin] (20:06 - 20:27)
All right. Sounds good. But we'll do that after the break.

Regina, I've mentioned before on this podcast, our introductory statistics course, Demystifying Data, which is on Stanford Online. I want to give our listeners a little bit more information about that course.

[Regina] (20:27 - 20:37)
It's a self-paced course where we do a lot of really fun case studies. It's for stats novices, but also people who might have had a stats course in the past, but want a deeper understanding now.

[Kristin] (20:37 - 21:12)
You can get a Stanford Professional Certificate as well as CME credit. You can find a link to that course on our website, normalcurves.com. And our listeners get a discount.

The discount code is normalcurves10. That's all lowercase. Welcome back to Normal Curves.

Today, we are pitting men against women to see who is better at guessing average erect penis length. And Regina, you were about to start us off on a discussion about problems with self-report studies.

[Regina] (21:13 - 21:16)
Right. Honesty. Are these men being honest?

[Kristin] (21:16 - 21:22)
You might expect that there might be a little overestimation rounding up a little fudging. Yes.

[Regina] (21:22 - 22:10)
Exactly. Researchers call this social desirability bias. And, Kristin, it's such an interesting problem.

Something we always need to keep in the back of our mind when we are reading survey studies. So, let's talk about it. But then also talk about clever ways that researchers can try to fix this problem.

And, Kristin, some people do this more than others. In the 60s, a couple of researchers came up with a little measurement scale to quantify how much people want to be seen in a socially desirable way. The Marlowe-Crowne scale.

33 true-false questions. And I thought it would be fun to read some. I have them right here.

Yeah, I want to hear. All right, Kristin, true or false? I am always careful about the manner of my dress.

[Kristin] (22:11 - 22:24)
That would be a big false for me, considering that I'm, like, usually wearing running clothes. But, Regina, this is a true-false question, and there's an always in there. So don't people just know that whenever there's an always in a true-false question, you're supposed to pick false?

[Regina] (22:26 - 22:31)
You think things through, I think, maybe more than other people do.

[Kristin] (22:31 - 22:32)
I'm overthinking it, yeah, possibly.

[Regina] (22:32 - 22:42)
Yeah, yeah. OK, but I'm going to count you not socially desirable in your manner of dress. How about this one?

True or false? I always try to practice what I preach.

[Kristin] (22:43 - 22:59)
Oh, that's a tougher one, Regina, because they slipped in the word try. I always try to practice what I preach. You know, I might be able to say true on that one because I want to.

I hope that I always try. I mean, maybe I'm not trying very hard.

[Regina] (22:59 - 23:06)
I briefly entertained the idea for a moment of practicing what I preach and then quickly discarded it.

[Kristin] (23:06 - 23:07)
Yeah, so I might score a true on that one.

[Regina] (23:08 - 23:13)
True or false? I am always courteous, even to people who are disagreeable.

[Kristin] (23:14 - 23:23)
OK, nobody can answer true to that one. Come on. No, of course.

I have to say false, and anybody who's being honest is going to say false on that one.

[Regina] (23:23 - 23:29)
I don't know. I'm wondering if maybe 1960, like you had to pretend to be courteous no matter what.

[Kristin] (23:29 - 23:31)
You're right. You're right. 1960 is a little different time.

Yeah.

[Regina] (23:32 - 23:41)
Right. 2025, big difference. All right, this one.

My table manners at home are as good as when I eat out in a restaurant.

[Kristin] (23:43 - 24:24)
That one, again, is a big false. Again, maybe 1960s, everybody's sitting prim and proper at the table at home. We're like eating while running out the door.

So I'm going to say false on that one.

[Regina]
With the dog. Don't forget the dog.

[Kristin]
Oh, yeah, my dog. I have not trained him well. He's always begging me for food.

So he's sitting there with his big eyes looking up at me. So, yeah, my table manners at home. I'm blaming it on the dog.

[Regina]
All because of the dog.

[Kristin]
All right, I see where you're going with this, Regina. These true and false is you get a score.

They're going to add up every time you pick the socially desirable, likely untrue answer. And you get a total score from 0 to 33. And a higher score is going to mean you are more of like what we call it a people pleaser.

[Regina] (24:25 - 24:38)
Yes, exactly. They said when they developed these sentences, they were things that you were supposed to do, but that very few people actually do. And it's culturally anchored.

So it's, you know, the U.S. in 1960.

[Kristin] (24:38 - 25:13)
A little like a lie detector test. If you score high, it's a little bit of lie detecting, right? Right, right.

I just thought of a problem, though. I'm taking this test right now on a podcast. And I know it's socially desirable to be honest.

So maybe I am only being honest because I know other people are going to hear it. And I want to look good about being truthful. And what if people taking this questionnaire are doing the same thing and saying, you know, I want to look honest.

And I know the honest answer is I don't have great table manners at home. So this is a little meta. But don't you think this is kind of gameable?

[Regina] (25:13 - 25:21)
This is hilarious. And it is totally gameable. And now everyone who's listening to this episode is going to go ahead and game it now.

[Kristin] (25:22 - 25:27)
We have just ruined all of social science because now everybody's going to get a zero. And that's on us, Regina.

[Regina] (25:28 - 25:40)
You know, there is at least one more social desirability scale out there in the 90s, a more modern one. And I am not going to tell you that one. I am going to keep it secret for your own good.

[Kristin] (25:40 - 25:52)
So we haven't spoiled all of social science research. Excellent, Regina. All right, Regina, can we get back to the penises for a moment?

How does the social desirability scale, Marlowe and Crowne, how does it relate to penises?

[Regina] (25:52 - 26:08)
Yes, back to penises. There was one study in 2019, Journal of Sex and Marital Therapy. It looked at social desirability and self-estimated penis size.

In young college men, they found a positive correlation.

[Kristin] (26:08 - 26:31)
Oh, so the more these men wanted to be seen as socially good, socially appropriate, the longer their penises were. Maybe that's not a coincidence. Maybe it's that the men who are willing to lie on these social desirability questions, they may also be willing to exaggerate their penis length a little bit because they want to look good to others.

[Regina] (26:32 - 26:47)
Maybe they believe it. Right, it's probably not some sort of weird causation where I was born with an extra long penis, and that has caused me now to have more social desirability tendencies.

[Kristin] (26:48 - 26:50)
I might expect it to go the other way, actually.

[Regina] (26:51 - 27:20)
Now, that study was done by a researcher at Clemson University. Name is Bruce King. He's emeritus professor of psychology now, and he also has a great review paper from 2022, Archives of Sexual Medicine, and he talks about what a problem social desirability is in all sexual behavior surveys, and he talks about how to use these sorts of scales to calibrate when asking people sensitive questions.

[Kristin] (27:20 - 27:36)
Oh, I love it. So, he's trying to use these kinds of questionnaires to maybe statistically adjust for somebody's score, right? So, if they score high in the social desirability, they're probably exaggerating a little on penis length, so we're going to downgrade, you know, we're going to give them a little bit of a penalty.

[Regina] (27:37 - 27:43)
The penis penalty? Penalizing the, oh wait, penalizing the people-pleasing penis.

[Kristin] (27:43 - 27:45)
That's good, Regina. Write that down.

[Regina] (27:46 - 28:01)
Thank you. Maybe we can sell that somehow.

[Kristin]
Yes, exactly.

[Regina]
You put each participant's social desirability score in the statistical regression model, just like you would other covariates, age or weight, and then control for them.

[Kristin] (28:02 - 28:23)
Right, and we've talked a lot in this podcast about what it means to statistically control for things. So, we're putting that social desirability score in the model to essentially give the penis penalty, and you probably could use this in other contexts, right? Like nutrition studies, exercise studies, it would flag people who are a little more likely to round up or fudge, and you give them a little penalty, statistically, mathematically.

[Regina] (28:23 - 28:45)
Exactly. So, I looked it up. They have done this in nutrition studies, exercise studies, sexual behavior, consumer behavior, criminal justice, drug and alcohol behavior, all kinds of things.

But when I was researching this, I found that they have developed other little tricks to get an honest answer out of participants, ones that rely a little bit on psychology.

[Kristin] (28:45 - 28:48)
Ooh, I love these little tricks. So, tell us some, Regina.

[Regina] (28:49 - 29:01)
One of my favorite tricks is, if you're doing the interview in person, is to hook up the person to an impressive-looking machine that does absolutely nothing, but you tell them it's a polygraph machine.

[Kristin] (29:01 - 29:11)
Oh, a fake lie detector test. It's kind of like sham surgery. I imagine that would make people a little more honest if they were worried about getting caught in their lying.

[Regina] (29:11 - 30:21)
Right? I cannot believe that this is still a thing. It has a fancy name.

It's called the bogus pipeline method. Oh, I like it. They first did it in 1971, but they are still using it for interesting things.

[Kristin]
Like what?

[Regina]
For one, they found when you hook people up to a fake lie detector machine, they all of a sudden report having had more sexual partners than if they're not hooked up.

[Kristin]
Well, is this men or women, though?

[Regina]
Both, but great question. This fake lie detector effect or whatever affected women more than men. This other study, I found this fascinating, along the same lines.

So, they would hook women up to a device and tell them that the device would be able to measure their true emotions and their emotional responses. And then they give the women sexy movies to watch and ask them how aroused they are, how hot and bothered they are. And the women, when they are hooked up to this fake lie detector test, they all of a sudden report more arousal than without it.

They're being more truthful about being aroused.

[Kristin] (30:21 - 30:23)
Right, because otherwise you might not want to admit.

[Regina] (30:24 - 30:26)
Right, right. They want to be nice girls.

[Kristin] (30:26 - 30:30)
All of these surveys have to be given in person, though, in order to be able to implement this little trick.

[Regina] (30:31 - 30:49)
This cannot be an online survey. Yes. Another psychology trick, you can distract people when you are asking them questions.

So, you can have them memorize a list of numbers, like a phone number or something, and then ask them the question, because the cognitive overload apparently makes people fall back into honesty.

[Kristin] (30:50 - 31:05)
Really? Oh, that is a really good trick, Regina. So, you're saying like women could ask their husbands to memorize a grocery list, and then you ask them, where were you last night? Ooh, I love it.

[Regina]
I think it might work, because apparently it takes effort to lie.

[Kristin]
That's so fascinating.

[Regina] (31:06 - 31:15)
Another one, along the same lines, play a lot of loud music so people are distracted by the music and they tell the truth.

[Kristin] (31:15 - 31:29)
Oh, well, that's easier than handing them a list of things to memorize. Oh, but maybe you could do both. And, Regina, you should do this on your dates.

So, when they pick you up for dinner, here's a list of numbers you have to memorize.

[Regina] (31:29 - 31:45)
I would like you to remember these numbers throughout the entire evening. Keep them in your head. And by the way, how old are you?

And are we exclusive? Are you married? And I turn the radio up at the same time.

[Kristin] (31:46 - 32:03)
Well, also at the age of the men that you're dating, you're also slipping in a cognitive test at the same time. Because sometimes the men you date, they're a little on the older side.

[Regina]
They are a little on the older side.

[Kristin]
Like, how's that executive functioning coming along? And memory, you know? So, two birds, one stone.

[Regina] (32:04 - 32:14)
Two birds, oh my God. Okay, now we've just given it away to anyone I'm going to have a date with who is listening to this episode.

[Kristin] (32:14 - 32:38)
But hey, if they're listening to the podcast, then they get bonus points. So that counts even though they know your tricks.

[Regina]
Oh, there you go. This is incentive.

[Kristin]
You're going to have the age reader wand, the AGE reader wand that you're going to whip out. And that way you can learn a little bit about their age and maybe something about their penises.

As we talked about in an earlier episode, which everybody should go and listen to.

[Regina] (32:38 - 32:49)
On Sugar Sag. Sugar Sag, Sugar Sag.

Uh, yeah. I don't know if we want to patent this one yet, though. I think we might need to refine the methodology.

[Kristin] (32:50 - 33:04)
Well, yeah. We got to make it more implementable, right? So there has to be a reason they have to memorize the number and then the music playing loudly.

It has to be all under some kind of smoke screen. And then we're going to sell it.

[Regina] (33:04 - 33:04)
Absolutely.

[Kristin] (33:05 - 33:05)
Yes.

[Regina] (33:05 - 33:37)
There were other geeky approaches that researchers have come up with for asking sensitive questions. And you might know about these, actually. You want to hear them?

[Kristin]
Yeah, of course.

[Regina]
Yeah. So if I wanted to say to someone, hey, have you ever cheated on your partner?

I say, hold on before you answer, flip a coin. Don't tell me whether it's heads or tails. But if it's heads, answer yes, no matter what.

If it's tails, answer honestly. And this is called the randomized response method.

[Kristin] (33:38 - 34:16)
You know, I love this trick, Regina. I heard about this back in grad school and I just thought it was so clever because let's say the person answers, yes, I cheated on my partner. And then somehow their partner finds out.

They can just say, well, but I flipped the heads, honey. And so I had to answer yes, right? So it makes them feel protected because in some cases, they're forced to answer dishonestly.

The amazing thing, though, is you can extrapolate from this and get an accurate estimate of the prevalence of cheaters in your sample because we know that a coin flip has a 50% chance of getting a head so you can work it out with a little math. And I think this is really the beauty of statistics.

[Regina] (34:16 - 34:27)
I know. Stats is so cool.

I love it. But back to penises, Kristin. Back to penises.

I have an example of how researchers have used some clever psychology in a penis study.

[Kristin] (34:27 - 34:29)
Oh, right. We got to get back to the penises.

[Regina] (34:29 - 34:51)
Okay, good. This was 2014, Journal of Sexual Medicine. And researchers were all at Indiana University, Kinsey's old university.

And it was called the Condom Fit and Feel Study.

[Kristin]
Well, that's a good name for a study.

[Regina]
It was part of a larger study on testing two different types of condoms.

[Kristin] (34:51 - 35:10)
Oh, you know, Regina, I hadn't really thought about this until now, but actually there is a reason medically that erect penis length is important because for condoms to fit correctly, I suppose that condom companies have to know the distribution of erect penis lengths in the population. So actually the question we're looking at today isn't totally frivolous.

[Regina] (35:10 - 36:04)
Bingo, bingo. The other day I got a little curious. Is there a company where you can just send in your measurements and get a condom that is custom made for you, like a bespoke suit?

[Kristin]
Oh my goodness, personalized condoms. Is there?

[Regina]
There is a company that gives you an option of 10 lengths and 9 circumferences.

So you can get 90 different sizes.

All right, back to that condom fit and feel study. The researchers had a sample, a big sample, 1,800 men, and they wanted the length of their erect penis.

They took advantage of psychology. They told the men that they could get free condoms to test, but they had to accurately measure their penis and send in the correct measurement so their condoms would fit them perfectly.

[Kristin] (36:05 - 36:11)
Oh, that is so smart because people are going to be less prone to lie because they don't want to get one that doesn't fit later.

[Regina] (36:12 - 36:31)
Say a guy reported he's 7 inches and then he gets a 7-inch condom. In the mail, it's too big. Now not only does he not have a working condom, which is a bummer, but his penis also looks too small because it just fell right off in front of his partner.

[Kristin] (36:32 - 36:44)
That is not socially desirable.

You know, I love, Regina, how they're taking that social desirability bias and flipping it around to get people to do the right thing. So what did they find? Now I'm really curious because maybe these men were more honest.

What did they find on penis length?

[Regina] (36:45 - 36:56)
Yeah, the results were strikingly different than the other ones we've talked about so far. Median and mode were 5.5 inches. The mean was 5.6 inches.

[Kristin] (36:56 - 37:06)
Oh, wait. So now we're getting closer to the women's guess of 5.3 inches. This is fascinating.

So maybe the men weren't being so honest in the other studies.

[Regina] (37:06 - 37:17)
Well, no. And here's something even better. We can go a little deeper because the researchers posted their data.

We have their data.

[Kristin]
Oh, like open data?

[Regina]
Open data.

[Kristin] (37:17 - 37:21)
Wow. Are we going to put a link to this in the show notes too, Regina?

[Regina]
I absolutely will.

[Kristin]
Okay, great.

[Regina] (37:22 - 37:39)
Because it is fun. Yes.

I thought it would be fun to look at the variability so far.

[Kristin]
Oh, variability. Very important, especially when it comes to condom fit, the variability in many ways is more important than the mean because the condom companies are going to need to make sure that they're, you know, spanning the range.

They fit on everybody, right?

[Regina] (37:39 - 37:46)
So how about another stats quiz for this one?

[Kristin]
Oh, sure.

[Regina]
The third quartile was 6 inches.

What does that mean?

[Kristin] (37:46 - 37:58)
Okay, so third quartile, 75th percentile. That means 75 percent of men are 6 inches or less, and 25 percent are 6 inches or more.

[Regina] (37:59 - 38:03)
The first quartile was 4.7 inches.

Here's a question. Where does the middle half of men fall?

[Kristin] (38:03 - 38:16)
Okay, so that is the 25th percentile. So that is enough information to give me the interquartile range. The interquartile range is between 4.7 and 6 inches. 50 percent of men fall between that range.

[Regina] (38:16 - 38:28)
Very good. But get this. Okay, so we have these numbers. One study found that nearly half of men who were looking at penis lengthening surgery, they had lengths of 5.1 inches or more.

[Kristin] (38:28 - 39:17)
Oh, wow. But they're right in the middle 50 percent. They were not even in the lowest quartile.

They should know that, right? This is an important public health message for men's health, Regina. Again, the importance of accurate descriptive statistics.

[Regina]
Absolutely.

[Kristin]
All right. So, Regina, we're seeing in this condom fit and feel study that maybe we're getting closer to the ground truth.

Maybe the men are being more honest, which again is looking more like the women's guess and not the men's. But the fact is, it's still self-report, and in some ways the only way to really get the ground truth is to have an objective measurement where it's not the person measuring themselves. But I can imagine that would be quite awkward.

So, are there any studies that have done that?

[Regina]
There are. Yes, they have.

[Kristin]
The logistics of that, I can imagine, might be very tricky. I want to understand how they do that.

[Regina] (39:17 - 39:20)
The answer is very carefully.

[Kristin] (39:20 - 39:41)
All right. I want to hear about that. Sounds interesting.

But let's take a short break first.

[Kristin]
Regina, I've mentioned before on this podcast, our clinical trials course on Stanford Online is called Clinical Trials Design Strategy and Analysis. I want to give our listeners a little bit more information about that course.

[Regina] (39:41 - 39:50)
It’s a self-paced course, we cover some really fun case studies designed for people who need to work with clinical trials, including interpreting, running, and understanding them.

[Kristin] (39:51 - 40:35)
You can get a Stanford Professional Certificate as well as CME credit. You can find a link to that course on our website, normalcurves.com, and our listeners get a discount. The discount code is normalcurves10.

That's all lowercase.

Welcome back to Normal Curves. Today we are talking about whether women or men are better estimators of the average erect penis length in the general population.

Regina, let's take stock. So far, we've looked at self-report studies and the problems with those because people want to be socially desirable, so that tends to make them a little less honest and that can bias those studies. What's next?

[Regina] (40:36 - 40:47)
I think, Kristin, now we're ready to tackle studies where the investigators themselves did the measuring, not the men.

[Kristin] (40:48 - 40:50)
Right, an objective measurer. Measurer?

What do you call the person who does that measurement?

[Regina] (40:51 - 40:56)
Appraiser, a penis appraiser. I would like to be a penis appraiser, please.

[Kristin] (40:56 - 41:16)
Not me, thank you. But we're talking about an objective investigator, so you don't need the honesty quizzes. You don't need to trick people into telling the truth.

You have somebody go measure it who has no stake in it. This, though, I imagine is a little awkward and logistically tricky. So how would they even do this?

[Regina] (41:17 - 41:25)
Good question. And Kristin, I think this is a perfect example of why having a clear protocol for your experiment is so important.

[Kristin] (41:25 - 41:34)
We talk a lot about protocols in this podcast. Thinking through ahead of time your experimental methodology, very important, especially in a study like this.

[Regina] (41:34 - 42:02)
Mm-hmm. Methodological reproducibility. And Kristin, we've talked about how we have more trust in studies that do this well.

So I thought it would be fun right now to pretend that we are investigators. We are the penis appraisers, and we are going to talk through what we would need to think about to include in the protocol. What factors that might affect whether we could get a good quality measurement from every man every time?

[Kristin] (42:02 - 42:17)
Oh, yeah, that's a great idea. Since I probably will never work on a study for real like this, it's an interesting thought experiment to talk through all the parts of the protocol. First of all, you probably need private rooms for the men, which, I mean, that's a logistical challenge right there.

[Regina] (42:17 - 42:23)
Are they dark, right? Or are they brightly lit? You know, like fluorescent lighting?

Probably not going to help.

[Kristin] (42:23 - 42:57)
I'm thinking dark, but I don't know. And then, of course, like, when does the investigator come in the door with a tape measure? That's got to be a little weird.

It might be detrimental to the thing you're trying to measure.

[Regina]
Could actually erase the erectile effect.

[Kristin]
I like your language there, Regina.

And then what measuring tool are you using? You mentioned a yardstick. Are you just bringing a big yardstick, a hard ruler, a tape measure?

One thing, though, couldn't the men just take a picture of themselves, and then couldn't we measure from the picture? Wouldn't that be easier?

[Regina] (42:57 - 43:13)
They have tried that. I think that these were not getting very good results because you still have to hold up a ruler next to the penis, and you got to get it all lined up, and it might be hard to get down to, you know, a quarter inch.

[Kristin] (43:13 - 43:18)
It might be hard to hold up the ruler and the camera at the same time, is what you're saying.

[Regina] (43:18 - 43:32)
And the penis, maybe.

There is the issue of how the penis attains its erection in the first place.

[Kristin] (43:32 - 43:34)
Regina, remember, we're keeping this PG-13.

[Regina] (43:34 - 43:44)
Let's just say that one way is to give a man an injection in his penis.

[Kristin] (43:44 - 43:47)
Oh, like Viagra.

I mean, if you can do that, that would take away some of the embarrassment, I would guess.

[Regina] (43:47 - 43:54)
Right, as opposed to the other way, the old-fashioned way.

[Kristin]
Yes.

[Regina]
A little private time.

[Kristin] (43:55 - 44:04)
Yeah, and then you have to think ahead of things like, are you measuring in centimeters or inches to the nearest half inch, quarter inch, eighth inch, right?

[Regina] (44:05 - 44:24)
Oh, that's a good one.

How about where on the penis you are actually measuring? Top, bottom, side? What are you doing if it's curved?

Some of the studies I read, they included pictures to show exactly where they measured and whether they pushed the fat in, if they had a fatty belly or not.

[Kristin] (44:24 - 44:26)
Very detailed.

[Regina] (44:27 - 44:37)
Oh, right. A lot of detail, yeah. And if they had more than one penis appraiser, they did trial runs before the real experiment to make sure they were all getting close to the same number.

[Kristin] (44:37 - 44:46)
Oh, inter-rater reliability, Regina. Are there actually inter-rater reliability studies on measuring this in the scientific literature, for real?

[Regina] (44:47 - 44:47)
There are, believe it or not, yes.

[Kristin] (44:47 - 44:58)
You're kidding. There's like a whole swath of scientific literature that I'm just totally not familiar with. That's funny.

I also, we would need to think about like the gender of the penis appraiser. That might matter.

[Regina] (44:58 - 45:05)
Especially in relation to the sexual orientation of the participant.

[Kristin]
Right.

[Regina]
Yes.

[Kristin] (45:06 - 45:18)
So these are just a lot of examples of all the little details you need to think through ahead of time and write down so that everybody working on the study can measure everything the same way and also so that your study is reproducible by others.

[Regina] (45:19 - 45:27)
The best studies that I saw were ones that went into details about what they did. And like detail, great detail.

[Kristin] (45:28 - 45:47)
Imagine the lab meetings on those ones, Regina. Okay, so Regina, we've talked about the issue with social desirability. We've talked about having objective measures to try to get around that.

We've talked about putting together a good experimental protocol. But one thing I'm still wondering, who the heck volunteers for studies like this?

[Regina] (45:48 - 46:00)
Excellent question. Whose penises are we looking at and measuring?

[Kristin]
Right.

[Regina]
People who volunteer for these studies, perhaps maybe a little different from those who are not volunteering.

[Kristin] (46:01 - 46:12)
I would think so. Yeah, because who is willing to be measured? I mean, you probably are a particular type of man. Maybe somebody who's like super proud of their equipment and they want to show it off.

[Regina] (46:12 - 46:28)
Who is volunteering for this? We have volunteer bias. And you're right.

They're more likely to be on the larger side, not representative of the population, which is also a problem, as we've talked about, with studies in nutrition and health, this volunteer bias.

[Kristin] (46:28 - 46:48)
We talked about this with the vitamin D randomized trials. We got healthier people signing up for the trials. They had higher vitamin D than the general population to begin with.

[Regina]
And then there are issues of recruitment.

[Kristin]
That is a good one, Regina. Yeah, how do they find the men for these studies and approach them?

[Regina] (46:48 - 46:58)
Oh, it is fascinating. There was one study where they recruited men during spring break from a nightclub in Cancun, Mexico, called Daddy Rock.

[Kristin] (46:58 - 47:09)
Well, that is not a representative sample. Clearly, you know, Regina, that is such a good example that I might steal that to use in class because it is an excellent example of selection bias.

[Regina] (47:10 - 47:39)
Selection bias, of course, is when you select a sample that is not representative of the population in ways that are related to the thing that you're studying. And just to support the selection bias, Daddy Rock was billed as a place where, quote, anything goes, and it was known for its giant foam parties.

[Kristin]
Foam parties?

[Regina]
These, like, big vats of, like, whip cream where you jump around probably naked.

[Kristin]
Oh, okay.

[Kristin] (47:40 - 47:50)
So this is quite a select group, the people that are going to Daddy Rock. Maybe they're more proud of their body than average. Maybe they have larger equipment than average.

[Regina] (47:50 - 48:10)
Maybe, maybe. So Bruce King has this great paper, 2021 Journal of Sex and Marital Therapy. He talks about the research methods behind some of these studies, and here's another good one.

They recruited men from a gay nudist annual convention to have their penises photographed.

[Kristin] (48:12 - 48:22)
Well, that's quite clever, because if you're wanting somebody to volunteer for this kind of study, maybe a nudist group would be a good place to go, yeah. But again, may not be a representative sample.

[Regina] (48:23 - 48:45)
Perhaps. So you can't eliminate this problem entirely, but you can try to reduce it. There was one study, they recruited from men who came into a military hospital to a plastic and reconstructive surgery clinic, and they just did not recruit the men who came in for anything related to genitals, but anyone else.

[Kristin] (48:45 - 48:52)
Oh, that's clever, because they're already there at the clinic, but not for anything to have to do with their penis. Could be representative.

[Regina] (48:52 - 49:29)
One study recruited men from erectile dysfunction clinics.

[Kristin]
Oh, wait, isn't that a problem?

[Regina]
Yeah, so it seems weird in some ways, but bear with me.

Men with erectile dysfunction can often attain an erection with those shots that we were talking about, pharmacological help. So you can still measure their erect penis, but the advantage is they're already in the clinic and they're already having their penis examined anyway. So they're less likely to be volunteering just because they like to be naked and show off their penis to a bunch of people, like at the nightclub.

[Kristin] (49:29 - 49:33)
So it might be a more representative sample, might get closer to the ground truth.

[Regina] (49:33 - 50:02)
Right, and in that 2021 review article, Bruce King did a nice thing for us to help us get at this ground truth. He went through all the studies that he could find and narrowed it down to decent studies where investigators did the measuring themselves, so now we could ignore all the self-report studies, and narrowed it even further down to studies without big problems in their measurement protocol or big problems in selection bias.

[Kristin] (50:03 - 50:06)
So that Daddy Rock nightclub study went out of the pile, I'm guessing.

[Regina] (50:06 - 50:18)
Out of the pile. A lot of them went out of the pile, and he got it down to eight studies.

[Kristin]
Oh!

[Regina]
And he had the mean erect penis length and sample size for each one, so he calculated the weighted mean.

[Kristin] (50:19 - 50:31)
Oh, he pooled the data like a little mini meta-analysis. Well, this is great, Regina. This is the ground truth, or as close as we're going to get to the ground truth, so what did he find?

[Regina] (50:31 - 50:43)
I feel like we need a drumroll now.

Ready? 5.4 inches. So in our Starbucks units, just a bit over a tall, not a grande, not a venti, a tall.

[Kristin] (50:43 - 50:55)
Oh, that is so interesting. This is way lower than most of the self-report studies. That self-report bias is really big.

And this is very close to the women's guess. So does this mean the women win?

[Regina] (50:55 - 51:06)
Yes, the women won. The women in that study guessed 5.3 inches, very close, 5.4. The men guessed 6.2. Wrong. Sorry, dudes.

[Kristin] (51:07 - 51:10)
So, Regina, this just proves our thesis that women are smarter.

[Regina]
They are.

[Regina] (51:10 - 51:12)
When it comes to penises, at least.

[Kristin] (51:12 - 52:01)
Especially. All right, Regina. So I think we're ready to wrap this up now and rate the strength of the evidence for the claim, and we were pitting women against men today.

[Regina]
I'm going to turn that now into a claim that we can rate. So I'm going to say that the claim today is that the women's guess of 5.3 inches for the average erect penis length in the population is closer to the truth than the men's guess of 6.2 inches.

[Kristin]
That's very clever how you framed that.

I do have some inside knowledge already now. And so how do we rate that in this podcast? It's with our trademarked, highly scientific, 1-to-5 Smooch Rating Scale.

One means no evidence and five means strong evidence for the claim. Now the claim is in favor of the women. So, Regina, kiss it or diss it?

[Regina] (52:03 - 52:27)
Kiss it. Definitely.

That sounded dirtier than I intended. I am going to go with 4.5 smooches on this one. Really strong based on what we've seen today.

We've gone through all the biases, tried to account for them as much as possible. Still a hard problem. So we don't know for sure.

[Kristin]
It's a hard problem.

[Regina]
Oh, you got me. Nice job.

[Kristin] (52:28 - 53:08)
4.5 smooches. What about you?

[Kristin]
Regina, yeah, I see your point.

The ground truth is still elusive. The definitive study has not been done, I'm guessing. But I'm going to go 5 smooches.

[Regina]
No way.

[Kristin]
Because the claim is just that the women are closer than the men. I'm not saying that the women were exactly accurate with their guess of 5.3. But clearly, I think the women are doing a better job at estimating. And it looks to me like the men tend to overestimate. So, actually, that does men a disservice. Because then that makes some men, if they think the distribution is shifted to the right, that's going to make some men feel bad about themselves.

So they should listen to the women. Again, women are smarter.

[Regina] (53:09 - 53:16)
They are smarter. At least about penises. Methodological morals. Who wants to go first?

[Kristin] (53:16 - 53:17)
Why don't you go first, Regina?

[Regina] (53:17 - 53:23)
Okay. How about this one? When answers aim to please, the truth takes it to leave.

[Kristin] (53:24 - 53:28)
Oh, I love it. Social desirability bias. That's good.

[Regina] (53:28 - 53:28)
Yeah.

[Kristin] (53:28 - 53:35)
Mine is going to be, without descriptive statistics, you'll never know if you measure up.

[Regina] (53:37 - 53:42)
Ooh. I like how you got a little innuendo in there. Very nice.

[Kristin] (53:43 - 53:44)
It goes with the theme of the podcast today.

[Regina]
There you go.

[Kristin] (53:44 - 53:57)
Regina, this has been fascinating. And it wasn't just about penises.

I think the audience learned a lot about good practices in science and good little tricks you can use to get people to be more honest.

[Regina] (53:57 - 54:03)
Absolutely. Absolutely. It was not a shameless attempt to grab people's attention with penises.

[Kristin] (54:03 - 54:04)
Slightly shameless.

[Regina] (54:04 - 54:10)
Yes, only slightly. Thank you, Kristin. And thanks for listening, everyone.

[Kristin]
Thanks, everyone, for listening. Thanks, Regina.