https://youtubetranscript.com/?v=UgRaLmCOwYU
Alright, so I’m really kind of hoping that at least 30% of you will be severely unhappy with this lecture. And maybe that’s wrong, I’ll find out afterwards. This dimension of personality, agreeableness, is one of the dimensions that most particularly differentiate men and women. And obviously the differences or similarities between men and women is a matter of hot debate in our society. And I want to run through the science that’s associated with that. And then, well I guess then we’ll see what we conclude. Now you remember that the big five were derived from a statistical analysis of the content of language, eh? That’s kind of interesting because it means that insofar as any psychological theory in the history of psychology has been a theoretical with the possible exception of intelligence research, which was also, the IQ is also derived statistically. It was derived by Galton, or it was initially theorized by Galton in some sense back in the late 1800s, but what Galton thought of as eminence bears very little relationship to what the psychometricians measure as intelligence. So intelligence is a statistical construct, or IQ is a statistical construct. And the big five traits are statistical constructs. And what that means is that there are theoretical presumptions that went into their derivation, but it’s very difficult to think of them as political because the first hypothesis was only that the fundamental dimensions of personality would be reflected in the language, English to begin with, but then other languages as the research progressed around the world. It’s very difficult for me to understand that as a political theory. You know, because if scientific findings have political implications, then you have to wonder if the biases of the researchers put the political implications into the data before revealing them as data. But it’s very difficult to argue that, I think, with regards to trait theories. The other thing that happened with trait theories is that the statistical analysis suggested their existence. It wasn’t until after the traits were reasonably well identified, and this really started to kick in in the 90s, that we started to understand the potential biological basis, and even the nature, the descriptive nature of the traits. At the aspect level now, where you differentiate the big five into ten, there’s still aspects that we don’t know much about. We don’t really understand the difference between politeness and compassion. We know that liberals are more compassionate than conservatives, and conservatives are more polite than liberals. And we think that politeness is somehow associated with the tendency of conservatives to follow social rules. But that’s about, I would say that’s about all we know. Now we don’t even know how much difference there will turn out to be between politeness and compassion. But there are ongoing studies trying to understand the covariates and correlates of the aspects. And the same is true of the traits. There was a lot of argument about openness when it first was discovered statistically. Some people, like Hans Eysenck, who formulated some of the early three-dimensional models of personality, and that was extroversion, neuroticism, and psychoticism, which he thought would predict the proclivity towards schizophrenia, but actually turned out to be composed of low agreeableness and low conscientiousness. Eysenck didn’t even think that openness was a reasonable trait. He thought it was mostly captured by IQ. And actually that seems to be the case to some degree, because if you divide openness into intellect and into openness to experience, it looks like IQ loads on intellect, or at least the non-verbal part of IQ loads on intellect, where the verbal part of IQ tends to load more on openness, and so does openness to experience, and so does creativity. But this is all discovered after the fact. So now one of the things that’s happened as a consequence of parsing out personality into the big five traits, and also using other trait schemas, is that it’s quite clear that there are differences between the sexes, or if you like, differences between the genders. Now this is a thorny problem, and it’s thorny for a number of reasons. One reason is that it’s a dogmatic assumption, proposition, of social constructionists that gender differences are socially constructed. First of all, they separate out the idea of sex, which you could think of as biological sex, you could think of as chromosomal sex, I presume. That’s one thing, but gender, that’s a whole different thing. And gender is the manner in which men and women present themselves to the world in terms of differences in, well, anything that you can measure that’s above the fundamentally biological level. Maybe you could say anything above the chromosomal difference. I don’t exactly know where the distinction is supposed to be made between biological sex and gender. It’s not a simple thing to understand, but the proposition still obtains that if there are differences between men and women at the level of phenotypic manifestation, then they’re socially constructed. The problem with that is that it seems to be wrong, and not just a little bit wrong, but wrong right to the core. One of the things that I would like to propose to you is that the social constructionists only have theory on their side. I don’t believe they have any data to support their claims whatsoever. Now I also think that they wouldn’t accept the sorts of things that I’m going to talk to you about as data, but that’s a whole different argument. I don’t really understand how it’s possible for people in the modern world to reject scientific claims given that almost everything they do in their day-to-day life that has anything to do with technology whatsoever depends for its function on the validity of the scientific theories that underpin the technology. So what that means is that people who treat scientific data as if it’s just another form of information, socially constructed information, certainly don’t behave like that if you follow them around in the actual world. Now here is a proposition about agreeableness. I don’t know if this is the case, because as I said, there’s lots of things we don’t understand about the big five dimensions, but this is how I’ve worked it out for my own understanding, and it’s in accordance with the data insofar as I can determine that. Agreeableness seems to be the dimension between, we certainly know agreeable people are empathic and compassionate and polite. We know less about disagreeable people, although we know that they’re more likely to be male. Now you could associate being disagreeable with being more callous and more harsh and more selfish, in that if you had to bargain with someone who’s low in agreeableness, they would fight harder for their side of the equation than someone high in agreeableness would fight for theirs. Now there’s a couple of things about human beings that aren’t considered sufficiently, I believe, insofar as we conceptualize human personality, and one is that humans are unbelievably maternal, both genders. They have to be, because our babies are born, for a mammal of our size, the gestation period should be two years, not nine months. And so what that means is that human babies are really born premature, and you can tell that because, you know, like ungulates, deer, I think deer is an ungulate, doesn’t matter, pretty much as soon as they’re born, they can stagger up on their legs and start to run around, whereas a human baby isn’t doing that till 15 months or 13 months or 17 months or depending on the baby. And babies are pretty much completely helpless at birth, and so they need a tremendous amount of care, and then because we have such a large cortex and because we’re so behaviorally plastic, we have an extraordinarily long dependence and development period. It depends on the culture, but it’s a minimum of 13 years, and it can certainly extend far beyond that, and does in cultures where there’s a tremendous amount of inculcation of information. So we also know that maternal behavior is very common among mammals. I mean, the very definition of mammal in some sense has to do with maternal behavior because mammals, well, they bear live young and they produce milk, but they’re warm-blooded, and there’s some other characteristics. So the ability to care for helpless, frequently upset, dependent creatures for a very long period of time is part of our behavioral repertoire. Now then you might wonder, are there individual differences in the degree to which people are maternal? And I think that’s captured at least in part with agreeableness. It makes sense because on the positive pole of agreeableness, that’s where you get warmth and compassion and empathy and the desire to care for others and self-sacrifice, I would say. One of the things we’ll show later is that agreeableness is negatively correlated with income, which is exactly what you’d expect if you were negotiating with someone who was self-sacrificing because they’re not going to put forward their side of the power equation as forcefully as someone who is disagreeable. But in order to raise a baby, you have to be self-sacrificing. There’s no two ways about it. You might find that rewarding and worthwhile, but I don’t believe there is a parent who actually becomes a good parent who doesn’t put their child’s welfare first, and I think that’s particularly true of mothers, particularly in the first year after birth. It’s probably true right up to the age of three, but I think it’s virtually undeniably true for the first year. The question is, is that reflected in personality traits? Now, the other thing about people that’s worthwhile recognizing is that we’re hunters. People are carnivorous. We’re pretty damn good at bringing down big game. It’s reasonable to suppose that the reason that there aren’t as many large animals in North America as there are in Africa is because when human beings came into North America 15,000 years ago, they killed all of them. They killed all the mammoths. They killed all the giant bears. They killed all the cats. They killed all the, I think there were camels maybe. I can’t remember precisely. Anyways, there was a very large array of very large mammals, and they started to disappear pretty damn quickly after the period of time where people migrated into North America. Now, one of the theories is that in Africa, the animals and the people co-evolved so that the animals and the people had fallen into some sort of mutual stability, but in North America, that wasn’t the case at all. I don’t think it was that easy to bring down a mammoth with a spear. So, it was very destructive of people to do what they did, but it also says volumes about what human beings are like. It’s certainly the case that a non-trivial proportion of the human population still hunts, and they’ll do that for leisure, which is something that’s very difficult for people who aren’t hunters to understand. They’re almost all men, which I don’t think will come as a surprise to anyone. So I think that predatory aggression is on the other side of agreeableness, and we also know that the best predictor of whether or not you’re going to be in prison is low agreeableness. Now low conscientiousness also helps, but the fundamental marker of antisocial behavior insofar as it’s captured by the big five personality markers seems to be low agreeableness. And that you might also say, given that men are less agreeable than women, that that’s part of the reason why men are much more likely to be imprisoned than women. I think it’s between, I think it’s 91% of incarcerated criminals are male, but I’m certain that it’s above 80%. I believe it’s 91%. Now, one of the things about personality traits that you want to keep in mind is that they’re normally distributed. And you need to understand some things about the normal distribution if you’re going to understand how personality affects social outcomes. Because it looks like men are only about a half standard deviation less agreeable than women. And what that means, if you pull a given woman out of the population and a given man, you can by no means say for certain which of those two are going to be less agreeable. On average it’s going to be the man, but there’s not a huge difference in probability. It’s still quite highly probable that the woman will be the least agreeable of the two. Now a normal distribution presupposes a mean and then random distribution around the mean. And one of the things that you’ll learn in psychology is that variables are normally distributed. And that’s actually not true. Some variables are normally distributed and lots aren’t. And you need to know about the ones that aren’t because many of them are extremely important. Health is not normally distributed. Creative ability is not normally distributed. Anything that has to do with the human propensity to produce is not normally distributed. What happens is that in those situations almost everyone does nothing and a very tiny fraction of the people do everything. So for example, I suspect that the median number of records that you people have produced is zero. And that’s the case for very many phenomena that are associated with creativity. There are some things that are normally distributed and personality traits seem to be one of them. The effect of personality traits on production might not be, but the personality traits themselves are. And so you can see if you look at this distribution, this is something you really have to know and understand if you’re going to understand research in psychology. This is like a basic axiom of all the statistics. The first axiom is that the phenomena that you’re measuring are normally distributed. Generally when you do a statistical analysis you have to test to see if that’s true. And most statistics can handle a fair bit of deviation from normality without being rendered invalid. But the list of variables that I just described to you, say those that are associated with creative production, do not fall into that category. They have very long tails. They’re distributed according to something called the Pareto distribution, which we’ll talk about more when we get to conscientiousness and trade openness. Now you’ll see there’s a middle line there and that’s the mean and the median and the mode in a real normal distribution. And then the curve is divided up into equal sections, roughly four of them on each side of the distribution, so eight in total, that represent a way of representing the normal distribution. And so by the time you get out to three standard deviations above the mean, you’re talking about 0.1% of the population. The same thing is true on the other end, three standard deviations below the mean. So basically the entire population is encompassed within eight standard deviations. Now it’s not quite true because the tails keep going. There’s so few people out there at one point that they almost vanish. That doesn’t mean their existence is not necessarily important. One guy who’s six standard deviations below the mean and agreeableness might be the serial killer who kills 100 people. So those exceptions can still have extraordinarily powerful impacts. They’re just not statistically very common. Now the normal distribution for men and women overlaps quite a lot for most single personality traits. So women are half a standard deviation more agreeable than men. So you can imagine two curves that overlap with the female distribution being shunted slightly to the right. And so what that means, as I said, if you take out a random woman or a random man from the distribution, it’s somewhat of a toss-up who’s going to be more or less agreeable. However, if the situation is such that only the person who’s one in a hundred least agreeable ends up in prison, all of the people who end up in prison are going to be men. Because the consequence of shifting the curve slightly to the right is that when you move out to the left-hand side of the distribution, out, say, three standard deviations in the entire population, all of the people out there are going to be men. So what that means is that small differences in the mean, even if the distribution is the same shape, small deviations from the mean can produce huge social effects at the periphery. So here’s an example. There aren’t that many people who are five standard deviations above the mean in intelligence, but among them are a tremendous number of Nobel Prize laureates. Because you can understand with intelligence, it isn’t exactly how smart you are that matters. It’s how smart you are compared to other people. Because if you’re smarter than other people, you’re going to get to where everyone’s going faster. And it’s the fastest person who’s fastest at that who’s going to get there first. So comparative ability really, really matters when you’re looking at exceptional levels of ability, of productive output. It’s a rough law. So here’s a rule. This is called Price’s Law. The square root of the number of people in a domain do half the work. That means if there’s 10,000 neuroscientists, 10,000 publishing neuroscientists, 100 of them have half the publications. And most of them have zero or one. So the rule for publications is among PhD students is the median number of publications that PhD students have is somewhere between zero and one. Half as many have two. Half as many of that has three. Half as many as that have four. So it’s a tremendous step down in productivity. It’s an exponential step down in probability with a linear step up in productivity. It’s a very, very frightening fact. Now it accounts for why 1% of the population has a huge chunk of the money. But you know, if you take that 1% and you divide them into 99% and 1%, the top 1% of the 1% has almost all the money that the top 1% has. And then if you take the top 1% of 1% and you divide them into 99% and 1%, the top 1% of that tiny slice has almost all of the money that that tiny slice has. So it’s also scalable. And it’s a problem because it means that productivity is always in the hands of a few. And no one knows what to do about that, or even if there’s anything that can be done about it, or even if there’s anything that should be done about it. So you might think of it as unfair. Well it’s certainly unfair in terms of egalitarian distribution of productivity. But what are you going to do about that exactly? It doesn’t seem like stopping the people who are hyperproductive from being hyperproductive constitutes a useful solution to that problem. So and even if you allow huge populations of people access to higher education, that might boost the overall levels of productivity, but it doesn’t change the distribution. Partly because it just makes everything more competitive, right? There is a definition of gender that basically, it’s basically the 1960s to 19, well to 2010, feminist description of gender. A socially constructed system of classification that ascribes qualities of masculinity and femininity to people. Gender characteristics can change over time and are different between cultures. Now there’s a variety of claims in that. One is that it’s socially constructed and the second is that it can change over, second and third, that it changes over time and are different between cultures. Of course it depends on what you mean by different, and that’s the key issue. On what measure, which is something you can’t not ask when you make a statement like that. But that’s the basic proposition. I think the truth of the matter actually is that you can’t make a one to one mapping of personality onto gender. But that doesn’t mean that personality is socially constructed. There isn’t a lot of evidence that it is. It’s certainly not socially constructed in such a way that it would allow the emergence of more than five dimensions. It might be socially constructed at least to the degree that one society can push people regardless of their gender or even regardless of their personality, farther up the distribution or farther down the distribution than another culture might. So we know for example that if you take kids who are adopted out, twins, and you want to produce a 15 point difference in their IQ by the time they’re 18, you have to have a minimum of three standard deviations difference in wealth between the families that they land in. So that’s what a one standard deviation increase intelligence costs and that’s a lot. It isn’t even obvious that that gain sustains itself across the entire lifespan because one of the things that happens is that as identical twins who were separated at birth and raised in different families age, their IQs become more like each other until by the time they’re about 60, their IQs are so similar that it’s as if you’re testing the same person twice. That’s weird, eh, because what you would think, you would definitely think that, well, once you separate the twins, the longer they stay apart, the more different they’re going to be, right, because you would assume that their environments stay different and the differences are going to accumulate across time and that they’re going to diverge, but that isn’t what happens at all. Okay, so let’s look at some interesting things here. So here’s one study. One of the things you might ask yourself is, why do boys like to play with trucks and girls like to play with stuffed animals and dolls, roughly speaking? And one answer is, well, that’s socially constructed. Parents, whether they want to or not, differentially reinforce toy preferences subtly and directly And as a consequence, the cumulative effect of that determines what toys the children are going to play with. It’s not obvious from the literature that that’s the case, but that’s not a theory that can explain this. So what the researchers did was take a whole variety of toys and have a number of people classify them as either feminine stereotyped or masculine stereotyped, and then they give them to a number of children to see which toys which gendered children played with. And they found that the male children tended to play with the stereotypically masculine toys given free choice, and the female children tended to play with the female stereotyped toys given choice. Well that doesn’t have anything to do at all with socialization hypothesis, except they did the same thing with rhesus monkeys. We compared the interactions of 34 rhesus monkeys living within 135 monkey troop with human wheeled toys and plush toys. Male monkeys, like boys, showed consistent and strong preferences for wheeled toys, while female monkeys, like girls, showed greater variability in preferences. Thus, the magnitude of preference for wheeled over plush toys differed significantly between males and females. The similarities to human findings, the top graph, by the way, is human subjects and the bottom graph is monkey subjects. On the left you see males. The black bar is masculine toys, and on the right you see females, where the black bar is masculine toys. Now what you see is the females are more likely to play with masculine and feminine toys, although they slightly prefer feminine toys, whereas the males overwhelmingly prefer masculine toys. The similarities to human findings demonstrate that such preferences can develop without explicit gendered socialization. We offer the hypothesis that toy preferences reflect hormonally influenced behavioural and cognitive biases, which are sculpted by social processes into the sex differences seen in monkeys and humans. Janice M. Hassett was the lead author on that paper. So that’s kind of a rough one. It’s not obvious at all why male rhesus monkeys would want to play with wheeled toys. I mean, what the hell, right? I mean, it’s not like rhesus monkeys are driving around in trucks. So it’s not exactly clear why these differences exist. When you’re thinking about how they’re responding to plush toys, those are basically pseudo-infants. So that’s kind of an easier thing to understand, especially because we know that the hallmarks of cuteness, which is the stimuli that are necessary to evoke basically a maternal response, the hallmarks of cuteness are pretty much stable across mammals, which is why people think kittens are cute. Well, any little baby thing is cute. The reason for that is big eyes and a little nose, and it sort of moves helplessly. It has short limbs. All of that sort of adds up to cute. Cute is a very powerful set of triggering stimuli. So if it wasn’t, obviously, children who were playing with little plush bears wouldn’t baby them, you know? Because obviously a plush bear is not a baby, but it’s similar enough to a baby schematically that it evokes, automatically evokes those sorts of responses. My daughter used to have this stuffed toy, and it was a cat, and I used to play with that cat. The only thing I used to do with it is you could actually push its head inside its little plush body. She did not find that the least bit amusing. So that’s a difference in masculine and feminine play patterns there, too. She knew perfectly well that this thing couldn’t be hurt. That wasn’t the issue. The behavioral responses that it evoked were part of a set, and it was perfectly healthy her to be responding as if this thing was deserving of care and compassion. She was practicing doing that. It’s a very important thing to do. It needs practice. I’ll read this to you. Now, I think some of the best research done on why gender differences exist outside of socialization has been done by Simon Baron Cohen. Simon Bar-Cohen? He’s Borat’s brother, by the way, just so you know. What he showed is that you might think that the classical human body type is female. So in some sense, every human creature starts out with a prototypically female body structure, and even though there’s chromosomal differences between the two sexes. What happens is that masculinization occurs as a consequence of fetal testosterone. There’s a lot of variation in fetal testosterone from male fetus to male fetus. Some of Cohen’s work has demonstrated quite clearly that fetal testosterone levels are very much associated with post-birth masculine behaviors. One of the things he’s found out, for example, he believes that autism is hypermasculinity, because he’s found that the fetal boys who are hypermasculinized are much more likely to become autistic. One of the things that’s interesting about autistic kids – there are autistic females as well, by the way, but most of them are male – is that the most fundamental lack they seem to have is the lack of ability to engage in any sort of social contact whatsoever. So they don’t make eye contact, and boys, by the way, boy babies make less eye contact than girl babies. The autistic kids, they don’t make hardly any eye contact at all, and they have a very difficult time establishing any kind of social relationship. Now this study is kind of interesting. So it was published in, I think it was 2012. Let me read it to you. This research has shown that prenatal exposure to endocrine disrupting chemicals can alter children’s neurodevelopment, including sex-type behavior, and that it can do so in different ways in males and females. Non-chemical exposure, including psychosocial stress, may disrupt the prenatal hormonal milieu as well. To date, only one published study has prospectively – that means over time – examined the relationship between exposure to prenatal stress and gender-specific play behavior during childhood, finding masculinized play behavior in girls who experienced high prenatal life event stress, but no associations in boys. Here we examine this question in a second prospect of cohort from the study for future families. Pregnant women completed questionnaires on stressful events, life events, during pregnancy, and those who reported one or more events were considered stressed. Families were re-contacted several years later – the mean age of their children was five years – and mothers completed the questionnaire, including the validated Preschool Activities Inventory, which measures sexually dimorphic play behavior. In sex-stratified analysis, after adjusting for child’s age, parental attitudes towards gender-atypical play, age and sex of siblings, and other relevant covariates, girls exposed to prenatal life event stress had higher scores on the PSAI masculine subscale and showed a trend towards higher or more masculine composite scores. By contrast, in males, there was a trend towards an association between prenatal stress and higher PSAI feminine subscale scores, but no association with masculine or composite scores. These data confirm previous findings in human and animal models suggesting that prenatal stress is a non-chemical endocrine disruptor that may have androgenic effects on female fetuses and anti-androgenic effects on male fetuses – androgenic being male hormone affected. This is Simon Baron Cohen, direct study. One of the tests, hypothetically, that you can use to assess empathy – although it turns out to be rather difficult to do that reliably – is to use what’s called the mind and the eyes test. Basically, with that test, what you do is you show subjects just a slice of a photograph of eyes. The person in the photograph had been manifesting some display of emotion, and some emotional displays are associated with change in eyes. For example, a Duchenne smile, which is a true smile, also involves lifting of the eyes at the edges, whereas just a fake social smile is just the mouth. You can read a smile from the eyes. You can’t read that as well as you could if you had the whole face. You can read anger from the eyes because the eyebrows – it includes the eyebrows – the eyebrows go down. You can read surprise. But it’s kind of attenuated because you don’t have the whole face. So hypothetically, people who are more attuned to social cues can do a better job of reading the mind and the eyes. So these researchers looked at children for whom fetal testosterone data was available and then determined at – how old were they? I don’t remember. It doesn’t matter. They had data on fetal testosterone from obviously from before birth, and then at some point in their child development, they were given this test. Empathy involves an understanding of what others are thinking and feeling and enables us to interact in the social world. According to the empathizing systematizing theory – now here’s the theory. The theory is that women are tilted towards empathizing and males are tilted towards systematizing. And that seems to fall into alignment with other observations suggesting that the biggest gender difference between adult humans is interest preference. Women are much more likely to express interest in occupations that involve a lot of social contact, whereas men are more likely to manifest interest in occupations that have to do with things. And so one example of that – you see this in the Scandinavian countries despite the fact that they’ve really done everything possible to flatten out the environmental differences between opportunities for boys and for girls – is that in the Scandinavian countries the ratio of male nurses to female nurses is one to twenty. And of female engineers to male engineers is one to twenty. And the governments now and then do a big push to try to get more men into nursing and more women into engineering. With a lot of push and a lot of advertising and marketing and so forth they can shift the proportions to some minor degree, but as soon as they stop pushing hard they just snap back to one in twenty. It’s really interesting if you think about it that the biggest gender differences that are reported in the world are reported between men and women in Scandinavian societies because those are the most gender equal societies in the world. And so one of the perverse things that has happened is that – you can imagine that there’s some reason that men and women are different is because of environmental variability, right? The environment for the women and the environment for the men is different. And then some proportion is due to genetic variability. And so then one idea which is false is that if you eradicated the environmental variability the gender differences would disappear. That would only be the case if all the gender differences were due to environmental variability. What happens instead is that when you eliminate the environmental variability you maximize the genetic variability and the reason you do that is because that’s all that’s left, right? You’ve eradicated the other source of variability so the only thing left is genetic variability. And the consequence of that is that men and women differ more in Scandinavia than they do in any other place on the planet. Now that to me seems like the death knoll of social construction theories because it’s exactly the opposite of what would have been predicted. Precisely the opposite. You know and maybe it would have been a good thing if flattening out the opportunity landscape would have eradicated gender differences in personality and preference and so forth. But it isn’t self-evident that that’s a good thing because you could also say that an egalitarian society optimally constructed is one in which the differences between people are allowed to manifest themselves so that each person is able to find a place and a niche in the society that actually fits their temperament. Empathy involves an understanding of what others are thinking and feeling and enables us to interact in the social world. According to the empathizing systemizing theory, now part of the systemizing theory as well is that one of the things about autistic people is that they systematize like mad. You know so to the degree that their cognitive abilities are intact which is extraordinarily variable it’s more often the case that if an autistic child focuses on something they do it obsessively and what they do is classify and systematize to a degree that looks uni-dimensional and well uni-dimensional and fundamentally focused. According to the empathizing systemizing theory, females on average have a stronger drive to empathize than males. This sex difference may in part reflect developmental differences in brain structure and function which are themselves under the influence of fetal testosterone. Previous studies have found that fetal testosterone is inversely backwards correlated with social behaviors such as eye contact and infancy, peer relationships and preschoolers and mentalistic interpretation of animate motion. Male fetuses are exposed to higher levels of testosterone than are female fetuses. The present study investigates empathizing in children as a function of amniotic measures of fetal testosterone. 193 mothers of children, 100 males, 93 females, aged 6 to 8 years of age completed children’s versions of the empathy quotient which is a questionnaire I believe and children themselves were tested on reading the mind in the eyes task. All mothers had had amniocentesis during the second trimester of pregnancy. There was a significant negative correlation between fetal testosterone and scores on both measures. While empathy may be influenced by postnatal experience, the results suggest that prenatal biology also plays an important role mediated by androgen effects in the brain. These results also have implications for the causes of disabilities involving empathy such as autism spectrum conditions and may explain the increased rate of such conditions among females. Here’s some differentiators between compassion and politeness. Compassionate people feel others’ emotions, inquire about others’ well-being and sympathize with others’ feelings. Polite people respect authority, hate to seem pushy and avoid imposing their will on others. So there’s the non-overlapping distributions that I talked to you about. The probability that a randomly drawn woman will be more agreeable than a randomly drawn man is 63%. So 6, if you do random pairs 10 times, 6 times the woman will be more agreeable than the man that you chose. So you see that it’s not a, in some sense it’s not a tremendous difference. It deviates from 50-50 obviously but it still leaves a lot of room for the claim that men and women are basically more similar than they are different. But then again it depends on where in the distribution that you’re looking because of the increasing effects of a difference in distribution as you move farther and farther out to the edges of the population. Women are more extroverted than men by 0.15 of a standard deviation. In particular they’re more enthusiastic at the aspect level. Enthusiastic people seem to manifest a lot of positive emotion. So it’s quite interesting because one of the things that that seems to imply is that we know that women are also more sensitive to negative emotion. So women actually seem to have a broader range of emotional expression than men. They’re more prone to positive emotion and they’re more prone to negative emotion. The UN indexes of gender equality and economic development are associated with larger differences in agreeableness but not in extroversion or neuroticism. So basically if you rank countries by how favorably they look upon equal rights and how much they’ve been able to put that in practice, the countries that rank higher in rights for women produce women and men who are more variable on agreeableness rather than less. But you don’t see the effect with extroversion and neuroticism. Occupational preference. It’s the people things dimension. Men prefer working with things and women with people. And the difference is almost a full standard deviation. And the end is 500,000. So you know when you’re starting to get up to numbers like that in a study, it becomes increasingly more reasonable to consider it representative of the actual population. Holland, John Holland has produced a typology of jobs which he turns into an acronym which is REISEC. ReisEC, Imaginative, Artistic, Social, Entrepreneurial, I believe. And conventional. I’m not sure about the entrepreneurial one. Men show stronger realistic and investigative interests and women show stronger artistic, social, and conventional interests. Yeah, and there’s no differences in enterprising. It’s not entrepreneurial ability, it’s enterprising. It’s fundamentally the same thing. So how does that express itself in social terms? Well there are more men as was well known in science, technology, engineering, and mathematics. Now God only knows if that will be the case in 20 years because one of the things that’s happening to our society very rapidly is that men are bailing out of higher education institutions at a rate that’s nothing short of terrifying. So already in educational institutions, higher, you know, institutes of higher education, women radically outnumber men. And the rate at which that’s changing seems in itself to be increasing. Why that is is not so obvious. It’s also the case that in pre-higher education settings, increasingly girls outperform boys. And it’s also not self-evident why that is. It’s not a good thing. Here’s some gender differences in employment. One of the things that might interest you and might annoy you is that the most common occupation for women in 1956 was basically secretarial. That’s still the case. Although the names are different because it’s often administrative assistant or executive assistant but the job descriptions are fundamentally equivalent. There’s only 11% women in construction, 15% women in forestry, 19% women in mining, and 25% women in work that involves utilities. There are no female brick masons, block masons, or stone masons, 0.1%. Very, very few cement masons, concrete finishers, and terrazzo workers. Very few electrical power line installers and repairs, carpet floor and tile installers, heating, air conditioning, refrigeration mechanics and installers, structural iron and rebar workers, bus and truck mechanics and diesel engine specialists, miscellaneous vehicle and mobile equipment mechanics, installers and repairs, tile and do-make, die makers, tool and die makers, and roofers. All under 1%. Women. This is the 10 most female dominated occupations in the United States as of 2010. Secretaries and administrative assistants, 96%. Childcare workers, 95%. Receptionists and information clerks, 93%. Teacher assistants, 92%. Registered nurses, 91%. It’s all around 90 so I’ll stop saying that. Bookkeeping, accounting, auditing, maids, housekeepers, nursing, psychiatric and home health aides, personal and home care aides, and general office clerks. All of those are 85% are more female. Other differences between men and women. Men are taller than women on average, 5 inches. The average woman in North America is 5 foot 4 and the average man is 5 foot 9. The average man weighs 194 pounds and the average woman weighs 164 pounds. Men are 40 to 60% stronger in their upper body and their jaw size is much larger. That’s because jaws are used for aggression. They’re used for biting and so it’s a hangover from, if you will, a hangover from our more primordial past. Women have a higher proportion of body fat. They’re more resistant to disease. There are far more male homicide victims, 77%. There are far more male homicide perpetrators, 85%. If women kill someone, it’s usually an intimate partner or family member, 60% of the time. Whereas if men kill someone, it’s usually a non-intimate acquaintance or stranger. So obviously you’re much safer with a woman you don’t know. Predation, instrumental versus defensive aggression. 8% of the male population hunts and that’s 91% male. Now one of the things that is characteristic of modern culture is that we associate almost unthinkingly, axiomatically, agreeableness with virtue. And we think that compassion, empathy are virtues that should predominate in people’s virtue hierarchy and that they should be fostered. But one of the things that’s very much worth considering is that all virtues turn into vices if you push them far enough. And that’s part of the reason why they would be normally distributed, right? Because every trait has a range within which it’s functional and outside of that range, the probability that it will be functional starts to become very, very low. Now empathy, warmth, and compassion sound like very good things, but they can also be construed trusting, submissive, and compliant, which could be perceived as naivete, docility, and a tendency to follow rather than lead. Now we do know that one of the predictors of dependent personality disorder is high levels of agreeableness and that that is a disorder that is more characteristic of women. And anxiety disorders and depressive disorders are also much more prevalent in women. And that’s likely associated not with agreeableness but with high levels of negative emotion. Now this paper, 2001, is the effects of personality on executive career success in the US and Europe. Now you know everybody talks about the glass ceiling, right? And the idea that women make less money than men for the same amount of work. Well the first thing I would say is that’s not true for single people, just so you know. And it isn’t obvious that the reason that women make less money than men when they do is because of prejudice. So women are more likely to work part time, for example, and the reasons for that are pretty obvious. All you have to do is think about that for 15 seconds to figure out why. And the reason is that many women have children in their 30s and one of the ways of balancing the development of your career with the burden of having children, or the wonder of having children depending on how you look at it, is by working part time. Now one of the problems with that, well there’s two problems, potentially. Well I’ll show you the next slide before I get into that. Okay so, I’ll go to this next one, yeah. Okay so here’s some correlations, one of them is between how much money you make and your personality. So the correlation between neuroticism and how much money you get paid is negative point three. The more you are neuroticism, the less you get paid. Why? Why do you think that is? Well because you’re not confident in your own abilities. You have low self-esteem. And if you’re not confident in your own abilities and you’re anxious about your performance, the probability that you’re going to feel confident and calm about negotiating for more or even asking for a raise is quite low. Extraversion and money made, virtually no correlation, openness, no correlation, agreeableness, negative point two four. Now you might not think that those correlations are very large, but if the correlation between neuroticism and money made is negative point three, if you translate that into an effect size, this is called a binomial effect size distribution, just the effect of neuroticism will ensure that 65% of men make more money than average and 35% of women make more money than average. Just the effect of neuroticism. And if you add neuroticism and agreeableness together, I have to do the math because I have to take the square root, it’s point five. I can’t do that in front of a class unfortunately. It’s going to push it up to about 70, 30 or higher than that. There’s a little bit of a negative correlation between conscientiousness and money made. Ascendancy, how well you progress up the ranks. Yes? I don’t know because I didn’t look in detail into the models they used, so I was just going to stick to the zero order correlations. So ascendancy, negative point two one for neuroticism, negative point one four for agreeableness. The effects are larger if you total them. Let’s see. Here’s a good one. This is something to think about. Job satisfaction. The correlation with neuroticism is negative point four two. That’s a big one. One of the things that’s very interesting about neuroticism is it’s also a very good predictor of marital satisfaction. It’s interesting in that light to note that 70% of divorces are initiated by women. One reason for that is that men are impossible to get along with. The other possibility is that women are too sensitive to that and there’s no way of sorting that out. But it’s nonetheless interesting to note that that’s still where the gender difference lies. Correlation with job satisfaction, negative point four two. Correlation with life satisfaction, negative point four two. Correlation with career satisfaction, negative point four one. So one of the things you want to remember is that almost all the measures that purport to measure something like well-being or happiness or satisfaction are so contaminated with neuroticism that it’s not even clear that they’re measuring something different. You see agreeableness, the correlation with career satisfaction is negative point two. If you get men to rate their performance and you get their bosses to rate their performance, men rate their performance pretty much the same as the bosses rate their performance or maybe they rate them a little bit more. But if women rate their own performance, they rate their own performance as worse than their bosses rating of their performance consistently. And the predictor of that seems to be negative emotionality. Now you might wonder if negative emotionality is something that’s associated with lower levels of life satisfaction across a broad variety of measures, what possible use could it be? But then you have to wonder, well exactly how is the physical environment different for women and for men? And one clear fact is that at an individual level, at least in relationship to dominance battles with men, women are at a disadvantage not least because of their size. Now it is the case for example that women hit men in marital relationships more often than men hit women. But that’s the sort of statistic that makes you wonder about measures and statistics. What’s wrong with that measure? Exactly that’s exactly it. So it depends precisely on how you define hit. And it’s a very tricky thing because it could be frequency, it could be frequency, that certainly might be a measure. But the best measure would likely be something like damage per blow. Here’s a study of the differences between men and women at an aspect level. Women are more enthusiastic, one fifth of a standard deviation. They’re a little less assertive but not very much. Those are both elements of extroversion. They’re more compassionate, almost half a standard deviation. They’re about a third of a standard deviation more polite. There’s no difference in industriousness. Women are slightly more orderly than men. Here’s something to think about. This is something that I noticed for example when I was raising kids. So I would intervene when my kids were misbehaving far more often than my wife would. But if I could just shut up for five seconds when they were being annoying, then she’d intervene. And all that meant was my threshold for being annoyed by misbehavior was just slightly lower than hers. But what that meant in practice was because it was slightly lower, I ended up intervening far more often because I would get fed. You know, if it took her 63 seconds to get annoyed and me 60, what that would mean practically would be that I was intervening most of the time. So when women are a little bit more orderly than men too, so you might ask yourself what exactly that would mean for the division of labor in a household. Because what it suggests is that if there’s disarray in the household, the probability is such that the typical woman will get more annoyed about that faster than the typical man. And how that would translate into the manner in which household duties are distributed, I don’t know. But it’s important to remember that small differences at the mean level can produce very large differences in behavior. Women are lower in intellect and higher in openness. And I think that probably goes along with the interest dimension. We saw already that women are more interested in artistic pursuits than men are. And that makes sense because we know that the openness to experience part of openness is a predictor, for example, of whether you’re in the humanities or in the sciences in university. So intellect predicts, roughly speaking, interest in the sciences and openness to experience predicts interest in the humanities and the arts. Women are half a standard deviation more agreeable. This is at the big five level. And four-tenths of a standard deviation more sensitive to negative emotion. So the two really big traits that differentiate men from women are agreeableness and negative emotion. Now you might ask, here’s another chart that’s quite interesting. Motivation variables by big five traits. Evenings worked. Extroverts. Extroverts are more likely to work evenings. Agreeable people are less likely to work evenings. Now that’s interesting, eh? Because you might think that if they were agreeable, they’d work more evenings. But I suspect that what’s happening with the agreeable people is that because their primary commitment is to intimate relationships, they’re more likely to consider their primary domain their responsibilities to intimate partners of various sorts, and so they’ll forego work for that reason. Conscientious people, work is more central to their life, and it’s also the case with open people. So the correlation between agreeableness and hours worked is negative point one six. The correlation between agreeableness and the hours of work that someone desires is negative point one seven. Here’s some things that predict relationship instability and divorce. Most personality traits have substantial effects on mating and parenting related behaviors such as sexual promiscuity, relationship stability, and divorce. Promiscuity and the desire for multiple sexual partners are predicted by extroversion, openness to experience, neuroticism, especially in women, positive schizotomy, which we won’t bother with, and the dark traits like narcissism, psychopathy, and Machiavellianism. Negative predictors of promiscuity and short-term mating include agreeableness, conscientiousness, honesty, humility in the hexical model, which is a six-dimensional model, and autistic-like traits. Relationship instability is associated with extroversion, low agreeableness, and low conscientiousness. That’s high extroversion, low agreeableness, and low conscientiousness. That’s tilting quite hard towards psychopathy. So someone who’s really extroverted and really low in agreeableness, they tend to be narcissistic. That’s not necessarily a problem if they’re high in conscientiousness, because you can still – they might be selfish and after their own interest, but if they’re high in conscientiousness, if they tell you that they’ll do something, they’ll do it, and generally you can expect that they’ll tell you the truth. If they’re low in conscientiousness, well then you have a big problem, because they tend to be somewhat parasitical, which is one way of defining low conscientiousness, and disagreeable, so they only care about themselves, and extroverted, so they’re very dominant and outgoing. So finally, neuroticism, low conscientiousness, and to a smaller extent, low agreeableness, all contribute to increase the likelihood of divorce. Now in this study, there was a 16 PDF study done, you can’t see it here because it’s cut off on the slide a couple of years ago. What they did, it’s quite interesting, instead of just looking at the zero order correlations between gender and personality, they summed all the differences to see what the overall difference was between men and women. So you’d have one normal distribution that was men and another normal distribution that was women, and then you could see how much they overlapped if you summed up all the gender differences, and the answer was they were three standard deviations different in total, which is a whopping difference. It meant that the personality distributions of men and women only overlapped in total by 10%. They found in the 16 PDF study, that’s an old personality scale that was originally formulated by Cattell, and it was a precursor to the Big Five. The reason they used it was because they had historical data that many thousands of people had filled out, so the fact that it wasn’t psychometrically arrayed properly didn’t mean there was no information in it. So women were higher in sensitivity, warmth, and apprehension. Warmth and apprehension you could associate it with agreeableness and neuroticism. Men were more emotionally stable, more dominant, more rule conscious, and more vigilant. Now one last thing. This is something to think about. How do men and women differ in the way they evaluate mates? Well, here’s a study. partners. Lifetime occurrence of simultaneous partners, so that was someone who was in a sexual relationship with more than one person at the same time, and lifetime frequency of simultaneous partners from one very seldom or never to five very often. Here’s their assumption. The number of partners a member of sex A acquires is an index of how often this individual is chosen by the other sex. It’s just a definition. It’s an indication of reproductive fitness as judged by members of the opposite sex. Results, male criteria. For women, the correlation between their fertility rates and the number of partners in the previous year was .94. So that’s basically markers of biological youth and also markers of biological health like symmetry or waist to hip ratio, which actually tends to be correlated with reproductive fitness, because women with lower waist to hip ratios are generally healthier, because especially in youth, the acquisition of abdominal fat is often an indicator of subpar physical health. The correlation between the fertility rate and the number of partners in the previous year is .94. That’s all of it. You never see a correlation of .94 anywhere, ever. Males choose fertility, indicators, beauty, waist to hip ratio, youthful appearance, neonotinous facial features. Neonotinous means like an infant. So one of the markers of feminine beauty is a face that has small childlike features. Female criteria. All respondents. The correlation between socioeconomic status and frequency of simultaneous partners. For men, it’s .5. So the higher the status of the man, the more likely he has simultaneous sexual partners. So it means he’s going out with someone sexually at the same time. For men, it’s .49. For women, it’s zero. Age 30 and over. Correlation between socioeconomic status and frequency of simultaneous partners. For men, it’s .8. For women, it’s zero. Age 30 to 39. The correlation between socioeconomic status for women and frequency of simultaneous partners. For men, it’s .92. That’s a very small N, though. For women, it’s .11. Female criteria for men. It might reflect the tendency on the part of females to choose high status partners during their own peak reproductive years. This might account especially for the strong relationship found in men between the age of 30 and 39. Women who typically prefer men three to eight years older than they are would then be in their mid to late 20s, a time when fecundity and thus sensitivity to male resources is at its peak. Supporting evidence. I don’t believe that, by the way. I don’t think that women pick men for their socioeconomic status. I think that women pick men for their ability to climb the status hierarchy because we forced women in an experiment that we never published to choose between those two things. Wealth versus ability. The women overwhelmingly chose ability. They just use wealth as a marker of ability. Yeah? It was an honors thesis. Often, honors thesis, even if they’re publishable, drift into the thing I’ll do next month, and then they stay there forever. Because it’s actually quite hard to turn an honors thesis into a publishable paper. If there isn’t some single person driving that forward, it’s not going to happen. That was the only reason. Okay, so, trivers. Parental investment model contends that women are more likely than men to seek a mate who possesses non-physical characteristics that maximize the survival or reproductive prospects of their offspring and were examined in a meta-analysis of mate selection research. As predicted, women accorded more weight than men to socioeconomic status. Ambitiousness, character, and intelligence, and the largest gender differences were observed for cues to resource acquisition, status, and ambitiousness. Also, as predicted, gender preferences were not found in preferences for characteristics unrelated to progeny survival, like sense of humor and general personality. Where valid comparisons could be made, the findings were generally invariant across generations, cultures, and research paradigms. Well? So what do you think of that? You know, the most… One of the things that it strongly indicates is that men and women value different things. And that’s worth thinking about. Because the hypothesis, and I think this is especially strongly held among people who are very young, is that the differences are cultural and the life course is the same. So… But I don’t think there’s any evidence that that’s the case at all. I have a lot of experience dealing, for example, with large law firms. And one of the things that happens to large law firms, they’re very competitive, eh? And the people who are partners are making a tremendous amount of money. So it would be generally in excess of 300, 400 thousand dollars a year. Now, in order to do that, they have to go through virtual enslavement during their internship. It’s not called an internship, it’s called an arti… their articling. And then they have to be on call 80 hours a week. That’s the life. What happens is that they lose all their women in their 30s. They can’t keep them. And it’s not because they don’t try, because they try. And the reason they try is that there just aren’t that many people who are exceptionally able. And so the law firms are trying to keep every single person they possibly can, who’s exceptionally able, because those people produce profits for the law firm. It’s just in their best interest. But the women all quit in their 30s. Well, why? Well, there’s a bunch of reasons. The first reason is… Is that a woman who’s high in the socioeconomic ladder is going to pick a man who’s high in the socioeconomic ladder. She’s going to marry across or up. That’s what the data show. And what that means is that most female potential law partners in their early 30s are married to someone who makes a fair bit of money. So the absolute magnitude of their income is no longer as relevant as it would be if they were single. It’s also one of the factors, by the way, that’s contributing to the polarization of society into those who have a lot of money and those who have none. Because what happens is that men who are rich will marry women who are poor. But women who are rich will not marry men who are poor. And so what happens across time is that sort of grinds its way through the culture is that all the rich women are with rich men. And that increases the probability that wealth is going to pool in the hands of fewer and fewer people. What the women seem to come… What the women seem to… Realize or… Conclude? I would say it’s two things. One is that it’s just not that much fun to work for 80 hours a week. Really. And if you want to have a life outside of work, that’s not the way to do it. And so then you might ask, well, why would anyone work 80 hours a week? Because that’s the real question. It’s not why some women won’t, because obviously why would you? You know, the answer is, well, there’s a lot of status and there’s a lot of money associated with it. But the thing is, is that status is more important to men than it is to women. And I think that’s individually true and also genetically true. Because for men, status is associated with how attractive they are to women. Whereas for women, socioeconomic status has nothing to do with how attractive they are to men. In fact, if anything, one of the things you find, for example, is that as women are… Segregated, so to speak, higher and higher up the IQ distribution, the probability that they’ll get married goes lower and lower. And the reason for that is that it’s harder… You know, if you’re at the 95th percentile of intelligence, and you’re going to marry across and up, you’ve already limited to one in 20 people. Just to maintain the same level. And so if you’re very intelligent, very educated, and you also have a very high status job, if you’re a woman, well, first of all, you’re bloody intimidating to most men. And second, the probability that you’re going to choose from a spot in the hierarchy lower than you is very low. You’re just not going to be attracted to that person. And so what happens to women who are exceptionally intelligent is that the pool of acceptable mating partners starts to become vanishingly small. So that, combined with the propensity of women to judge 85 percent of men in online dating services as less attractive than average, makes it that much more difficult. Now, I should say, you know, all the prejudice is clearly not on the side of women, by no means, because if you look at male attitudes towards women in large online dating site studies, you’ll find that their preference for body configuration is 21 years old. And that doesn’t change as the male’s age. So, you know, the selection criteria on both the male and the female side are extremely harsh. So, so, think about that. See you. Thank you.