Statistics 101 or What I Wish People Understood About Gender

In December of last year, the Proceedings of the National Academy of Science published a study by researchers at Tel Aviv University, catchily entitled “The human brain mosaic”.

The great thing about it is that in one single piece of research, it sums up everything that I have ever wanted to scream at people.

To quote the abstract, “Brains with features that are consistently at one end of the “maleness-femaleness” continuum are rare. Rather, most brains are comprised of unique “mosaics” of features, some more common in females compared with males, some more common in males compared with females, and some common in both females and males. (…) These findings are corroborated by a similar analysis of personality traits, attitudes, interests, and behaviors of more than 5,500 individuals, which reveals that internal consistency is extremely rare.“

In other words, we are all individuals with unique brains and personalities.

So why is this so difficult for us to wrap our heads around? Why do we believe books that tell us “Men are from Mars, women are from Venus” and raise our children differently because “boys will be boys”? 

Probably because humans love simplicity, and they have a deep-seated need to categorize most anything they come across. We have to, in order to make sense of the immense amounts of data our brains take in every day. And gender is a very obvious category to resort to, even more so because it is immediately apparent in most people we meet: we are taught to dress, speak and behave a certain way according to our biological gender, firmly pigeonholing ourselves into one category or the other.

We’re just now coming to realize that the category is problematic and harmful to many people’s identities as well as their mental health. And here is why: The importance of gender as an explanation for our personalities and our behavior is vastly overestimated by most people. Gender, no doubt, in part influences our behavior and women and men, on average, differ on certain traits and characteristics.

But there are two important caveats to that.

1.)   Generalizations Are About Means But We Deal With Individuals

It is true that women, on average, are more religious and more risk-averse. First of all, though, these effect sizes tend to be small and unlikely to be noticeable in the interactions you have in everyday life. Secondly, “on average” means that someone added up a bunch of religiosity scores, divided them by the number of scores, and then had a look at the result for men vs. women. Mean differences tell you nothing about individual people. They summarize statistical data and are useful for calculating gambling odds, but they are useless in personal, real-life interactions. So, when you assume someone that you are interacting with in real life “must be X” because of their gender, without bothering to get to know them and find out if they really are X, you are stripping them of their individuality and refusing to acknowledge and appreciate their uniqueness as a human being.

2.)  Variance Explained, or Why Gender Explains Very Little

Bear with me while I explain the statistical concept of variance explained to you in the simplest, most unscientific way I can think of.

I love chocolate. I really do. On a dessert menu, I will always pick the most chocolatey thing, I will always pick chocolate over a burger or a steak, and even on a diet I sneak in a piece or two every day.

Is that because I’m a woman? The stereotype is that women like sweet things whereas men are more likely to go for a burger or a steak. And it’s true that women experience a different physiological response to chocolate! So maybe part of the reason that I enjoy chocolate too much is my gender.

But there are a million other things that could be contributing to my love of chocolate: the sugar content of my mother’s diet during pregnancy, how strongly my brain responds to sugar as an addictive substance in general, my number of positive childhood memories involving chocolate, the fact that chocolate is readily available in the culture I grew up in, the fact that my mother would never let me eat it and now I’m overcompensating…

It’s just that these factors are not nearly as visible as my gender is. So it’s much easier to think “Of course she loves chocolate, all women love chocolate” than “This person seems to really enjoy chocolate, maybe her brain exhibits a particularly strong response to sugary foods”.

If we generalize that, there are a million potential reasons why people’s liking of chocolate varies. Some of that variance may be due to variance in brain responses. Some of the variance may be due to variance in cultural background and upbringing. Some of it may be due to differences in diet during our mothers’ pregnancies, and so forth.

Only a tiny portion of the variance in our liking for chocolate is explained by gender differences. And yet, in chocolate and in life, we tend to focus on that explanation because it’s so easy and so readily available.

If you are more the visual type, please enjoy this angry feminist Venn diagram (my scanner cut off the grumpy smiley in the lower right corner).

So let’s stop resorting to the easiest explanation! Let’s recognize and appreciate each other in all our complexity and understand that there are various reasons for why people behave the way they do. Gender is one small part of people’s identities and not one that we can reduce human beings to.