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I’ve been very busy the past week or so. There’s a lot I could blog, but I just don’t have the time. I should mention that I’m now reading my friend Garett Jones’ book Hive Mind: How Your Nation’s IQ Matters So Much More Than Your Own. It’s a good complement to Joe Henrich’s The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter. Reading them in sequence reminds me of how One Explanation to Rule Them All is usually not a good fit with reality broken down into its more complex bits. I’m about ~2/3 of the way through Garett’s book, and it’s a pretty quick read. I feel a bit bad for Garett though because he has to spend so much time justifying the utility of intelligence testing (much of it reads like Intelligent: All That Matters). Like The Secret of Our Success I’d really recommend Hive Mind if you have a background that’s outside of its core area of economics and psychometrics; there’s a lot you’ll learn, and it’s not a heavy lift.
One the issues that Garett mentions in Hive Mind is that IQ is only a modest (though robust) predictor of income. This explains why there are so many stupid people who happen to be well off, and vice versa. Much of where you end up in life is stochastic, in addition to other factors like personal background (i.e., “connections”), appearance, and personality. That being said when looking at groups of people as a unit IQ is much more predictive. It strikes me that this is just a lot of the random/stochastic effects being cancelled out, as they’re not systematically biased. I think there’s a relationship here to the dynamics that Greg Clark explored in The Son Also Rises: Surnames and the History of Social Mobility. While Garett surveys spatial patterns, Greg was highlighting temporal (inter-generational) patterns.
What else is going on?
English
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Dutch
French
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Hebrew
Hindi
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Korean
Persian
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What else is going on? GO PATRIOTS! (Like my daughter, I am a 4th quarter play-offs fan).
Also, as an addendum to my thank you last week, I should mention that I am in the middle of Not by Genes Alone, and have The Humans Who Went Extinct (I should really be more disciplined and finish 1 book before starting another, but since I borrow from libraries rather than buy, and with different libraries and check-out periods, often a recently received book is due before one I am already in the middle) , and The 10000 Year Explosion on my night table, all, I believe, due to your recommendations. So again, thank you.
Is there any way to curate Twitter feeds? I follow you, amongst others, and I find a lot of intersting links and info via it. However, there is way too much noise in some interesting people’s twitter feeds, e.g. political opinions, mundane updates, that really dilute the signal.
http://westhunt.wordpress.com/2015/03/19/the-once-and-future-khan/
OK. Tme to put my kids to bed. :)
For some reason this comment asking for directions on how to curate twitter feeds reminds me of Gregory Chochran in his unmistakable style last year saying “I am not Razib, and I disagree with him on some things of importance: but I look forward to the day, a few years hence, when Razib is still cursing the ignorant commenters, while the New York Times is one with the dust of Nineveh and Tyre.”
http://westhunt.wordpress.com/2015/03/19/the-once-and-future-khan/
OK. Tme to put my kids to bed. 🙂
Interesting how things change without one noticing. Halfsigma’s blog and his old HBD posts are gone daddy gone. Now he’s transformed into The Lion of the Blogosphere https://lionoftheblogosphere.wordpress.com/2016/01/17/trump-is-looking-more-presidential/#comments
http://thesocietypages.org/socimages/2008/02/06/correlations-of-iq-with-income-and-wealth/
Some researches found that IQ is more correlated with income than wealth
Here is (moderate)correlation of IQ and income.
This makes sense since income is more ability dependent which is more IQ related. Incompetent person should not last long on the job in an efficient market.
Here is (weak)correlation of IQ and wealth.
The weak correlation of wealth and IQ is likely due to intelligence obscured by significant numberous other non-intelligent ways to achieve wealth like luck, special talent for specific situation(like baseball players), crime, inheritance ect. If research can control all other non-intelligent factors in wealth building, the wealth correlation with intelligence might go up.
Personally I knew a house keeper guy with only elementary education who inherit his former master big chunk of assets since his master has no offspring. With this inherited wealth, he build himself a middle class life in Boston with a reasonable beautiful wife. His mental ability is only good enough to get elementary school for sure. With all inherited wealth, he could not go further beyond elementary school if he is capable. By the end of his life, he pretty much used up most wealth.
I started watching the movie Prefontaine on NetFlix. “Pre” was a runner at the University of Oregon and this is big in the movie. Did you ever watch it Razib? I think this could start your new life as a runner.
Ethiopian skin color is paler than Sudanese who even located north of Ethiopia (higher latitude). Just like Himalayas, high altitude with cold climate makes Ethiopian spending more time in shelter and cloth.
Pale skin = low light = 1)nature low light areas, 2)cloth or shelter due to cold climate.
Any reader can contribute more if they knew other tropic regions with annual cold climate situation. If the pattern is consistent, we are making contribution of science here.Replies: @Razib Khan
Ethiopian skin color is paler than Sudanese who even located north of Ethiopia (higher latitude). Just like Himalayas, high altitude with cold climate makes Ethiopian spending more time in shelter and cloth.
https://upload.wikimedia.org/wikipedia/commons/9/94/Africa_1971_2000_mean_temperature.png
Pale skin = low light = 1)nature low light areas, 2)cloth or shelter due to cold climate.Replies: @AG
Despite Ethiopian living very close to equator, they still develop paler skin than their northern neighbors. Sheltered live style with clothing is a major contributor to skin color mutation.
Any reader can contribute more if they knew other tropic regions with annual cold climate situation. If the pattern is consistent, we are making contribution of science here.
I know we don’t want to talk too much about politics, it draws flies, stupid ideological flies. But, I expect many of us are fascinated by the republican primary race. What is fun to do is to watch carefully the odds of the three leading republican candidates to win the primary. I am a cautious and frugal betting man and when the opportunity presents itself I will make a wager. A day before the last election Obama was a 90% favorite to win over Romney, as per Nate Silver, but I could place a bet of 100 dollars to make 125. I hit it hard and told GNXP readers to do the same.
I predict what is going to probably happen right around the key March primaries is a similar betting opportunity where one of the the three candidates Cruz, Trump, or Rubio, is going to be a dead duck, as far as actual chance to win the republican primary and the brilliant Nate Silver will confirm it. Silver will make me Silver and I will share that information when and if that opportunity occurs. The gambling books allow bets on the rest of the field meaning you can bet against a candidate winning. I expect the time will come when one the three candidates has fallen out of the Republican field clown car but the odds do not reflect it. We shall see, if that opportunity occurs, I will be back to announce it.
Gambling markets are scientifically fascinating because they are incredibly predictive. Razib has talked about this once or twice in the past.
The Tibetan plateau has UV as strong as sea level equatorial Africa, but relatively pale skinned inhabitants.
It occurs to me that a plateau is the opposite of a valley, where it is easy to farm (as in “fertile valley”). If I remember Robin Dunbar’s book rightly on this, the existence of polyandry (usually brothers sharing a wife ) in Tibet is hypothesised to be due to the extreme difficulty of farming there, because even a skilled farmer had so much trouble making a living he could barely support a wife and child by his own efforts. So my guess is the pale skin of Tibetans, and the spread of SLC24A5 on the Deccan and Ethiopian you know whats, were due to women being in competition for a husband, and the crucial factor was the less desirable women were sometimes unable to secure any husband to support them and a child and so were unable to reproduce; hence there was selection for characteristics deemed desirable in that time and place . A world very different to our own.
Also, as an addendum to my thank you last week, I should mention that I am in the middle of Not by Genes Alone, and have The Humans Who Went Extinct (I should really be more disciplined and finish 1 book before starting another, but since I borrow from libraries rather than buy, and with different libraries and check-out periods, often a recently received book is due before one I am already in the middle) , and The 10000 Year Explosion on my night table, all, I believe, due to your recommendations. So again, thank you.Replies: @Razib Khan
what econ books are worth reading?
"Economics" is far too broad. Since you asked, I am going to address this to you, making some assumptions about your background knowledge and interests based on my having read your blogs for several years (not sure at this point how long, certainly since before Obama became president; I think I found you one site before you came to the Discover blogs, but I don't recall where that was at the moment). I came close to becoming an economic historian, and not a year has gone since that I haven't wondered about my decision not to, so this will lean toward economic history. Also, I will try not to blather too long, but rather return to this topic on future open threads, and am confident that you will tell me when enough is enough, before it becomes more than enough (Always leave 'em wanting more, you know.)
Kindelberger's Manias, Panics and Crashes. I read this back in graduate school in the 80s; I don't recall it in detail, but was impressed at the time, and its stock has climbed substantially since the events following the failure of Lehman Brothers. Who knows, we may in fact be living through a long term Kindleberger bubble.
Slee's No One Makes You Shop at Wal-Mart. This is an amazing introduction not only to game theory (with which I imagine you are familiar given your background and wide-ranging intellectual tastes), esp. the prison's dilemma, but also to how useful it is in thinking about interesting social and economic problems. It opened my eyes and I recommended it strongly to both of my children when they were in college (and both of whom I successfully discouraged from taking up, or even ever studying, economics).
Keynes's The Economic Consequences of the Peace. Perhaps the most prescient analyses of public policy ever. Well written: Keynes is well regarded as a stylist, except perhaps when he had to struggle intellectually and than convey those results to others (as in The General Theory). Elucidates much about events in interwar Europe, and implicitly explains why the 20-30 years after WW2 was so different.
Beckert's Empire of Cotton & Baptist's The Half Has Never Been Told. 2014 was a banner year for topics related to American slavery. Beckert's is a history of what, over the last 2 millennia, has been the single most important manufacturing industry in most societies that were, by contemporaneous standards, technologically advanced. It embeds US slavery in a long international history of the industry. Outside of professional historians, those who know me deem me to be considerably more knowledgeable about history than is common among educated Americans. Unfortunately I have my blinders -- e.g., my knowledge is focused on US and European history (I've learned much from suggestions about history on this blog: e.g., IIRC, Findlay and O'Rourke's Power and Plenty: unfortunately it was recalled before I finished it) -- and this book taught me much about RoW (the rest of the world). Baptist's book is about U.S. slavery as both a social system and an economic system (i.e., a system of production) and how it evolved over time, becoming more efficient as slavers learned how to get more cotton production out of not only their land but their forced labor.
I have not read Dani Rodrik's Economic Rules, but Rodrik is one of the wiser public economists and the book is therefore worth a mention. Also Piketty: I got half-way through the book before the group I was reading it with fell apart due to work pressures and have not yet returned to it. The book has 3 threads: documenting the history of inequality in modern economies over the last 2-3 centuries, explaining them historically and esp. economically, and making a policy suggestion. Pretty much all the controversy it has generated concerns the last two; I don't think anyone credible questions the empirical claims, the history presented, and one can learn a lot from this.
This is plenty for now (I hope I have not fallen into the role of the old man who, once asked for his opinions, does not STFU). Like I said, unless (until?) discouraged, I will return to this with more suggestions in future open threads (I hope this will not be sufficient dis-incentive for RK to stop having open threads).
i’ve seen it. the guy died 😉 albeit in a car crash. i lived in eugene and went to UofO, can’t avoid the legend Pre.
Any reader can contribute more if they knew other tropic regions with annual cold climate situation. If the pattern is consistent, we are making contribution of science here.Replies: @Razib Khan
both ethiopia and s. asia show selection for slc24a5 above & beyond their west eurasian ancestry.
She said all countries around Ethiopia are darker, even southern Egyptian (Nubian people). Only dark Ethiopians are the ones living on low land at borders with other countries, who are minor in numbers. So high elevation might contribute to the selection of slc24a5 ?(through clothing or shelter?).
Fascinating stuff.Replies: @John Massey, @Sean
After commenting here, I just talked to an Ethiopian lady who is at my work place. She could be easily mistaken for an Egyptian.
She said all countries around Ethiopia are darker, even southern Egyptian (Nubian people). Only dark Ethiopians are the ones living on low land at borders with other countries, who are minor in numbers. So high elevation might contribute to the selection of slc24a5 ?(through clothing or shelter?).
Fascinating stuff.
Next to the coffee brown Oromo people from Ethiopia, the Kenyan highlanders are shiny black.
Hot tip: Barring illness/injury (she has a bone spur in her foot which gives her intermittent difficulty), the Ethiopian girl Genzebe Dibaba will win the 1500m (she smashed the long standing world record at the 2015 World Championships in Beijing) and she's a hot chance in the 5000. I guess she might even have a crack at the 10,000, depending on the race scheduling. (She has an Amharic name, so her real name is just Genzebe. Her father's name is Dibaba. But it seems sports officials can't cope with that, so in races they just label her Dibaba, which is problematic when she runs against her older sister Tirunesh.)Replies: @AG
IQ is correlated with wealth on the group level in good part because of non-IQ (though nonetheless equally heritable) factors that are also correlated with IQ, such as future time orientation.
I finally finished Joe Henreich’s book. I have to say that while I found most of the book edifying, the last three or so chapters lagged for me, due to his attempt to bring all of his evidence into a “theory of everything” for human cultural development. While the earlier chapters were rife with interesting studies and observations, the end felt to me like an extended just-so story to me, and hence was much less gripping.
My biggest issue with his model is his emphasis that social learning has always been more important than “genius.” I do agree that genius is typically overrated compared to minor elaboration upon the existing cultural toolkit of society. But I’m not sure it can be entirely discounted as a factor in the development of modern societies which have seen “scientific revolutions.” Genius often tends to be associated with, as Judith Rich Harris would put it, a deficiency in terms of groupness. Many great inventors, artists, and polymaths have biographies which show them fitting in quite poorly with their peers and often taking to conventional instruction quite badly as well. Such people probably are a liability in a small, traditional group, as there is no social role for the bright eccentric. But in a modern society, particularly one where international commerce exposes the populace to a wide variety of ideas, it is easier for the socially awkward and defiant to find their own way to flourish.
You need to have unique personality to be some 0ne like Galileo who does not care about fitting in. Certainly introvert personality enjoying solitude is great for genius thinking process. Correlation between introversion and IQ also breeds genius. Newton and Einstein developed their theory in isolation. Newton even did not care to publish his discoveries which were hidden away for very long time.
My biggest issue with his model is his emphasis that social learning has always been more important than "genius." I do agree that genius is typically overrated compared to minor elaboration upon the existing cultural toolkit of society. But I'm not sure it can be entirely discounted as a factor in the development of modern societies which have seen "scientific revolutions." Genius often tends to be associated with, as Judith Rich Harris would put it, a deficiency in terms of groupness. Many great inventors, artists, and polymaths have biographies which show them fitting in quite poorly with their peers and often taking to conventional instruction quite badly as well. Such people probably are a liability in a small, traditional group, as there is no social role for the bright eccentric. But in a modern society, particularly one where international commerce exposes the populace to a wide variety of ideas, it is easier for the socially awkward and defiant to find their own way to flourish.Replies: @AG
This makes sense since scientists tend to be concerned with objective evidences than social approval (or social validation). It is against human nature to do so. Most people feel terrible and threaten when facing social disapprovals. Popularity is nice feeling for most people.
You need to have unique personality to be some 0ne like Galileo who does not care about fitting in. Certainly introvert personality enjoying solitude is great for genius thinking process. Correlation between introversion and IQ also breeds genius. Newton and Einstein developed their theory in isolation. Newton even did not care to publish his discoveries which were hidden away for very long time.
Hello Razib
I used yourself and Steve Hsu in my comment about academic merit on Steve’s post of an interview with a grad student about cognitive genomics. I understand if you find it not worth your time to look at given you have already determined I am an asshole when I previously pointed out that you don’t really understand the aspirations of the people I come from.
http://infoproc.blogspot.com/2016/01/cognitive-genomics-interview.html
That may be the case indeed, but I would posit that the obverse is also possible. That is, a small, close-knit traditional group (i.e. a small English village) may tolerate an eccentric due to kinship and/or long-term inter-family social relationships while a society with a larger, diverse population with weaker “organic” ties may enforce uniformity of thought or behavior more strenuously and disallow eccentricity as such in order to bind the disparate peoples together.
Multiculturalism alone likely is not enough. After all, the Roman Empire was hugely multicultural and widely literate, but (AFAIK, Razib can feel free to school me here) outside of a few areas such as architecture didn't really build that much on the corpus of knowledge bequeathed by the Greeks. And after the Abbasids, the Caliphate was not particularly scholarly. It may be that empires organically develop their own cultures of social stability which eventually subsume the most brilliant thinkers in slightly more conventional directions. As a contemporary example, I've long suspected that the modern academy's shift away from interdisciplinary studies has been to the detriment of human learning, given some of the most profound insights are found when one applies knowledge of one domain to another field.
And let’s not discount personal effort (I know genes get the big nod most of the time here).
I happen to know a fairly large set of multimillionaires, and while almost all of them are quite above average in intelligence, the wealthiest among them is probably the least intelligent amongst them (he also came from the least well-off family). But he is extraordinarily hardworking. He is a “hustler” par excellence. And he is EXTREMELY money-oriented.
(Seems to have gotten lost – not shown as being in moderation, so I’ll try again).
“Economics” is far too broad. Since you asked, I am going to address this to you, making some assumptions about your background knowledge and interests based on my having read your blogs for several years (not sure at this point how long, certainly since before Obama became president; I think I found you one site before you came to the Discover blogs, but I don’t recall where that was at the moment). I came close to becoming an economic historian, and not a year has gone since that I haven’t wondered about my decision not to, so this will lean toward economic history. Also, I will try not to blather too long, but rather return to this topic on future open threads, and am confident that you will tell me when enough is enough, before it becomes more than enough (Always leave ’em wanting more, you know.)
Kindelberger’s Manias, Panics and Crashes. I read this back in graduate school in the 80s; I don’t recall it in detail, but was impressed at the time, and its stock has climbed substantially since the events following the failure of Lehman Brothers. Who knows, we may in fact be living through a long term Kindleberger bubble.
Slee’s No One Makes You Shop at Wal-Mart. This is an amazing introduction not only to game theory (with which I imagine you are familiar given your background and wide-ranging intellectual tastes), esp. the prison’s dilemma, but also to how useful it is in thinking about interesting social and economic problems. It opened my eyes and I recommended it strongly to both of my children when they were in college (and both of whom I successfully discouraged from taking up, or even ever studying, economics).
Keynes’s The Economic Consequences of the Peace. Perhaps the most prescient analyses of public policy ever. Well written: Keynes is well regarded as a stylist, except perhaps when he had to struggle intellectually and than convey those results to others (as in The General Theory). Elucidates much about events in interwar Europe, and implicitly explains why the 20-30 years after WW2 was so different.
Beckert’s Empire of Cotton & Baptist’s The Half Has Never Been Told. 2014 was a banner year for topics related to American slavery. Beckert’s is a history of what, over the last 2 millennia, has been the single most important manufacturing industry in most societies that were, by contemporaneous standards, technologically advanced. It embeds US slavery in a long international history of the industry. Outside of professional historians, those who know me deem me to be considerably more knowledgeable about history than is common among educated Americans. Unfortunately I have my blinders — e.g., my knowledge is focused on US and European history (I’ve learned much from suggestions about history on this blog: e.g., IIRC, Findlay and O’Rourke’s Power and Plenty: unfortunately it was recalled before I finished it) — and this book taught me much about RoW (the rest of the world). Baptist’s book is about U.S. slavery as both a social system and an economic system (i.e., a system of production) and how it evolved over time, becoming more efficient as slavers learned how to get more cotton production out of not only their land but their forced labor.
I have not read Dani Rodrik’s Economic Rules, but Rodrik is one of the wiser public economists and the book is therefore worth a mention. Also Piketty: I got half-way through the book before the group I was reading it with fell apart due to work pressures and have not yet returned to it. The book has 3 threads: documenting the history of inequality in modern economies over the last 2-3 centuries, explaining them historically and esp. economically, and making a policy suggestion. Pretty much all the controversy it has generated concerns the last two; I don’t think anyone credible questions the empirical claims, the history presented, and one can learn a lot from this.
This is plenty for now (I hope I have not fallen into the role of the old man who, once asked for his opinions, does not STFU). Like I said, unless (until?) discouraged, I will return to this with more suggestions in future open threads (I hope this will not be sufficient dis-incentive for RK to stop having open threads).
(I’ve tried a couple of times to reply, but it seems to disappear – not shown as in moderation, which is what usually happens, just no sign of it. Is the reply too long? I’m not going to try again until I hear back).
She said all countries around Ethiopia are darker, even southern Egyptian (Nubian people). Only dark Ethiopians are the ones living on low land at borders with other countries, who are minor in numbers. So high elevation might contribute to the selection of slc24a5 ?(through clothing or shelter?).
Fascinating stuff.Replies: @John Massey, @Sean
If you look at long distance running, you can find some nice contrasts – I choose that field because Ethiopian (notably the Oromo people) and Kenyan highlanders now absolutely dominate competitive middle to long distance running, because they both have high altitude adaptation. (Unfortunately, it appears that Kenyan athletes also have a problem with doping, but I digress). The two groups are also bitter rivals on the running track. They are very easily separated by skin colour – and also in the case of the Ethiopians, by head shape and hairline, interestingly; they tend to have very wide foreheads.
Next to the coffee brown Oromo people from Ethiopia, the Kenyan highlanders are shiny black.
Hot tip: Barring illness/injury (she has a bone spur in her foot which gives her intermittent difficulty), the Ethiopian girl Genzebe Dibaba will win the 1500m (she smashed the long standing world record at the 2015 World Championships in Beijing) and she’s a hot chance in the 5000. I guess she might even have a crack at the 10,000, depending on the race scheduling. (She has an Amharic name, so her real name is just Genzebe. Her father’s name is Dibaba. But it seems sports officials can’t cope with that, so in races they just label her Dibaba, which is problematic when she runs against her older sister Tirunesh.)
High landers good at running long distance make me think of their bodies ability to deal with hypoxia at high elevation. Most limiting factor at long distance running is tissue hypoxia.
It’s possible, but as Henreich notes (and many others, including myself, have realized independently) cultures which foment great advances in relatively short periods have certain traits in common. They all occur in trading nations where the public is exposed to foreign ideas to some degree. Think Ancient Greece, Abbasid Central Asia, renaissance Italy, or the British Isles during the modern period.
Multiculturalism alone likely is not enough. After all, the Roman Empire was hugely multicultural and widely literate, but (AFAIK, Razib can feel free to school me here) outside of a few areas such as architecture didn’t really build that much on the corpus of knowledge bequeathed by the Greeks. And after the Abbasids, the Caliphate was not particularly scholarly. It may be that empires organically develop their own cultures of social stability which eventually subsume the most brilliant thinkers in slightly more conventional directions. As a contemporary example, I’ve long suspected that the modern academy’s shift away from interdisciplinary studies has been to the detriment of human learning, given some of the most profound insights are found when one applies knowledge of one domain to another field.
Next to the coffee brown Oromo people from Ethiopia, the Kenyan highlanders are shiny black.
Hot tip: Barring illness/injury (she has a bone spur in her foot which gives her intermittent difficulty), the Ethiopian girl Genzebe Dibaba will win the 1500m (she smashed the long standing world record at the 2015 World Championships in Beijing) and she's a hot chance in the 5000. I guess she might even have a crack at the 10,000, depending on the race scheduling. (She has an Amharic name, so her real name is just Genzebe. Her father's name is Dibaba. But it seems sports officials can't cope with that, so in races they just label her Dibaba, which is problematic when she runs against her older sister Tirunesh.)Replies: @AG
Interesting.
High landers good at running long distance make me think of their bodies ability to deal with hypoxia at high elevation. Most limiting factor at long distance running is tissue hypoxia.
She said all countries around Ethiopia are darker, even southern Egyptian (Nubian people). Only dark Ethiopians are the ones living on low land at borders with other countries, who are minor in numbers. So high elevation might contribute to the selection of slc24a5 ?(through clothing or shelter?).
Fascinating stuff.Replies: @John Massey, @Sean
I suppose high ground in the tropics can get that cold at night, but not when the sun is up so vit D from the sun isn’t affected. It is often sub zero in the 1000-meters-above-sea level Kalahari desert of a winter night. Interestingly the Bushmen natives of the Kalahari do need shelters and clothing in the middle of the day, to protect them against the SUN! (Silberbauer 1981).
It could be that up on the Ethiopian and Deccan plateaus a lack of resources for raising children meant that looking appealing with lighter baby skin was at a premium, hence explaining SLC24A5 spreading like gangbusters, while the Kalahari natives’ relatively light skin (and even North Asians’) may have been a different solution to the same problem (childbearing under insufficient resources).
I think the light skin variant of SLC24A5 (wherever it came from) got more common in farmers as they went north, because their crops were not adapted to northern climes, and it was like trying to farm on a plateau for a long time. Scant resources meant male provision was necessary, and environment-obligate monogamy somehow put light skin at an advantage.
I’m not sure if Judith or Peter is correct about exactly what was going on, but as skin is light or dark rather than diverse, I would guess Judith’s explanation is pretty close to the truth.
From what I recall, the #1 predictor of wealth is personality, and in particular a lack of fatalism. If you think you’ll fail no matter how hard you try, you usually fail. IIRC the effect was roughly twice as strong as IQ, and half as heritable. I don’t have the paper handy unfortunately, but I’ll post it if I can find it. It makes intuitive sense – if you think putting money aside will have little to no effect on your future, you won’t save.