Heckman and social mobility

Great discussion at Marginal Revolution of the debate in Boston Review between James Heckman (economics Nobelist) and others about social mobility and public policy. Heckman admits that cognitive ability is hard to change through early intervention, but wants to argue that "non-cognitive skills" (e.g., conscientiousness, rule-following, long term planning, etc.) can be inculcated. His evidence, however, seems restricted to two small sample size studies.

Heckman also appears in a recent This American Life broadcast.

Heckman:

... life success depends on more than cognitive skills. Non-cognitive characteristics—including physical and mental health, as well as perseverance, attentiveness, motivation, self-confidence, and other socio-emotional qualities—are also essential. While public attention tends to focus on cognitive skills—as measured by IQ tests, achievement tests, and tests administered by the Programme for International Student Assessment (PISA)—non-cognitive characteristics also contribute to social success and in fact help to determine scores on the tests that we use to evaluate cognitive achievement.

Second, both cognitive and socio-emotional skills develop in early childhood, and their development depends on the family environment. But family environments in the United States have deteriorated over the past 40 years. A growing fraction of our children are being born into disadvantaged families, where disadvantage is most basically a matter of the quality of family life and only secondarily measured by the number of parents, their income, and their education levels. And that disadvantage tends to accumulate across generations.

Third, public policy focused on early interventions can improve these troubling results. Contrary to the views of genetic determinists, experimental evidence shows that intervening early can produce positive and lasting effects on children in disadvantaged families. This evidence is consistent with a large body of non-experimental evidence showing that the absence of supportive family environments harms childhood and adult outcomes. Early interventions can improve cognitive as well as socio-emotional skills. They promote schooling, reduce crime, foster workforce productivity, and reduce teenage pregnancy. And they have much greater economic and social impact than the later interventions that are the focus of conventional public policy debate: reducing pupil-teacher ratios; providing public job training, convict rehabilitation programs, adult literacy programs, and tuition subsidies; and spending on police. In fact, the benefits of later interventions are greatly enhanced by earlier interventions: skill begets skill; motivation begets motivation.

Social and Educational Mobility: Denmark vs USA (James Heckman)

Despite generous social programs such as free pre-K education, free college, and massive transfer payments, Denmark is similar to the US in key measures of inequality, such as educational outcomes and cognitive test scores. 

While transfer payments can equalize, to some degree, disposable income, they do not seem to be able to compensate for large family effects on individual differences in development. 

These observations raise the following questions: 

1. What is the best case scenario for the US if all progressive government programs are implemented with respect to child development, free high quality K12 education, free college, etc.?

2. What is the causal mechanism for stubborn inequality of outcomes, transmitted from parent to child (i.e., within families)? 

Re #2: Heckman and collaborators focus on environmental factors, but do not (as far as I can tell) discuss genetic transmission. We already know that polygenic scores are correlated to the education and income levels of parents, and (from adoption studies) that children tend to resemble their biological parents much more strongly than their adoptive parents. These results suggest that genetic transmission of inequality may dominate environmental transmission.

  

See 

Genetic correlation of social outcomes between relatives (Fisher 1918) tested using lineage of 400k English individuals 

Game Over: Genomic Prediction of Social Mobility

The Contribution of Cognitive and Noncognitive Skills to Intergenerational Social Mobility (McGue et al. 2020)

Note: Denmark is very homogenous in ancestry, and the data presented in these studies (e.g., polygenic scores and social mobility) are also drawn from European-ancestry cohorts. The focus here is not on ethnicity or group differences between ancestry groups. The focus is on social and educational mobility within European-ancestry populations, with or without generous government programs supporting free college education, daycare, pre-K, etc.

Lessons for Americans from Denmark about inequality and social mobility 

James Heckman and Rasmus Landersø 

Abstract Many progressive American policy analysts point to Denmark as a model welfare state with low levels of income inequality and high levels of income mobility across generations. It has in place many social policies now advocated for adoption in the U.S. Despite generous Danish social policies, family influence on important child outcomes in Denmark is about as strong as it is in the United States. More advantaged families are better able to access, utilize, and influence universally available programs. Purposive sorting by levels of family advantage create neighborhood effects. Powerful forces not easily mitigated by Danish-style welfare state programs operate in both countries.

Also discussed in this episode of EconTalk podcast. Russ does not ask the obvious question about disentangling family environment from genetic transmission of inequality.

 

The figure below appears in Game Over: Genomic Prediction of Social Mobility. It shows SNP-based polygenic score and life outcome (socioeconomic index, on vertical axis) in four longitudinal cohorts, one from New Zealand (Dunedin) and three from the US. Each cohort (varying somewhat in size) has thousands of individuals, ~20k in total (all of European ancestry). The points displayed are averages over bins containing 10-50 individuals. For each cohort, the individuals have been grouped by childhood (family) social economic status. Social mobility can be predicted from polygenic score. Note that higher SES families tend to have higher polygenic scores on average -- which is what one might expect from a society that is at least somewhat meritocratic. The cohorts have not been used in training -- this is true out-of-sample validation. Furthermore, the four cohorts represent different geographic regions (even, different continents) and individuals born in different decades.

The figure below appears in More on SES and IQ.

Where is the evidence for environmental effects described above in Heckman's abstract: "More advantaged families are better able to access, utilize, and influence universally available programs. Purposive sorting by levels of family advantage create neighborhood effects"? Do parents not seek these advantages for their adopted children as well as for their biological children? Or is there an entirely different causal mechanism based on shared DNA?

 

The figure below appears in Low SES does not decrease heritability of cognitive ability (N=300k).

 

Early intervention and long term outcomes

I wish I had made more of an effort to talk to James Heckman about his main research interests during the conference last week. My understanding is that while Heckman admits that cognitive ability is hard to change through early intervention, he believes that important "non-cognitive skills" (e.g., conscientiousness, rule-following, long term planning, etc.) can be inculcated. It would have been enlightening to hear more from the horse's mouth! Unfortunately for me he seemed to always be in conversation with other participants.

Brookings: ... Not one of the studies that has suggested long-term positive impacts of center-based early childhood programs has been based on a well-implemented and appropriately analyzed randomized trial, and nearly all have serious limitations in external validity. In contrast, the only two studies in the list with both high internal and external validity (Head Start Impact and Tennessee) find null or negative impacts, and all of the studies that point to very small, null, or negative effects have high external validity. In general, a finding of meaningful long-term outcomes of an early childhood intervention is more likely when the program is old, or small, or a multi-year intervention, and evaluated with something other than a well-implemented RCT. In contrast, as the program being evaluated becomes closer to universal pre-k for four-year-olds and the evaluation design is an RCT, the outcomes beyond the pre-k year diminish to nothing.

I conclude that the best available evidence raises serious doubts that a large public investment in the expansion of pre-k for four-year-olds will have the long-term effects that advocates tout.

This doesn’t mean that we ought not to spend public money to help families with limited financial resources access good childcare for their young children. After all, we spend tax dollars on national parks, symphony orchestras, and Amtrak because they make the lives of those who use them better today. Why not childcare?

It does mean that we need public debate that recognizes the mixed nature of the research findings rather than a rush to judgment based on one-sided and misleading appeals to the preponderance of the evidence.

Persistence, motivation and reliability

GED holders are roughly comparable to high school graduates in terms of cognitive ability, but weaker in terms of personality factors such as conscientiousness. Labor market outcomes for GED holders are closer to those of high school dropouts than to graduates.

Heckman talk (mp3) at Yale Law School (also available on iTunes). For related results on personality and earnings for cognitively gifted individuals, see Earnings effects of personality, education and IQ for the gifted.

The GED

James J. Heckman, John Eric Humphries, Nicholas S. Mader

NBER Working Paper No. 16064

The General Educational Development (GED) credential is issued on the basis of an eight hour subject-based test. The test claims to establish equivalence between dropouts and traditional high school graduates, opening the door to college and positions in the labor market. In 2008 alone, almost 500,000 dropouts passed the test, amounting to 12% of all high school credentials issued in that year. This chapter reviews the academic literature on the GED, which finds minimal value of the certificate in terms of labor market outcomes and that only a few individuals successfully use it as a path to obtain post-secondary credentials. Although the GED establishes cognitive equivalence on one measure of scholastic aptitude, recipients still face limited opportunity due to deficits in noncognitive skills such as persistence, motivation and reliability. The literature finds that the GED testing program distorts social statistics on high school completion rates, minority graduation gaps, and sources of wage growth. Recent work demonstrates that, through its availability and low cost, the GED also induces some students to drop out of school. The GED program is unique to the United States and Canada, but provides policy insight relevant to any nation's educational context.

This figure shows that high school completion probability varies mainly according to cognitive ability, whereas GED completion is positively correlated with low non-cognitive ability (i.e., low conscientiousness). (Numerical score 1 = low, 10 = high; click for larger version.)

The related question we will be facing in the near future: what are relative job success probabilities for students with degrees from a traditional college versus those with credentials obtained via online education? For example, consider a smart kid who obtains high grades in linear algebra and C++ from MIT/Harvard/Berkeley edX, but chooses not to attend university, versus a graduate from a traditional engineering program. Exactly what is being signaled or predicted by these two life paths? Who would you hire?

Low SES does not decrease heritability of cognitive ability (N=300k)

These researchers, from Stanford, Northwestern, and the University of Florida, analyze a large population of twins and siblings (~24k twins and ~300k children in total, born 1994-2002 in Florida). They find no evidence of SES (Socio-Economic Status) moderation of genetic influence on test scores (i.e., cognitive ability). The figure above shows the usual pattern of lower pairwise correlations in test performance between non-identical twins and ordinary sibs, consistent with strong heritability. (In figure, ICC = Intraclass Correlation = ratio of between-pair variance to total variance; SS/OS = Same/Opposite Sex.) The researchers find, via further analysis (see below), that lower SES does not decrease heritability. No large GxE effect at low SES.

Earlier work by Turkheimer and collaborators (with much smaller sample size) suggested that low SES can drastically reduce the genetic heritability of intelligence. Their result has been widely publicized, but over time evidence is accumulating against it.

Note that Economics Nobelist James J. Heckman is the editor at PNAS who handled this paper. Heckman is an expert statistician and one of the most highly cited researchers in the area of childhood education and human capital. He was also a vocal critic of The Bell Curve, but seems (now) to accept the validity of general intelligence as a construct, its heritability, and the difficulty of increasing intelligence through environmental intervention. He tends to focus on other, more trainable, factors that influence life success, such as (my interpretation) Conscientiousness, Rule Following, Pro-Sociality, etc. ("non-cognitive skills").

Socioeconomic status and genetic influences on cognitive development
PNAS doi: 10.1073/pnas.1708491114

Significance
A prominent hypothesis in the study of intelligence is that genetic influences on cognitive abilities are larger for children raised in more advantaged environments. Evidence to date has been mixed, with some indication that the hypothesized pattern may hold in the United States but not elsewhere. We conducted the largest study to date using matched birth and school administrative records from the socioeconomically diverse state of Florida, and we did not find evidence for the hypothesis.

Abstract
Accurate understanding of environmental moderation of genetic influences is vital to advancing the science of cognitive development as well as for designing interventions. One widely reported idea is increasing genetic influence on cognition for children raised in higher socioeconomic status (SES) families, including recent proposals that the pattern is a particularly US phenomenon. We used matched birth and school records from Florida siblings and twins born in 1994–2002 to provide the largest, most population-diverse consideration of this hypothesis to date. We found no evidence of SES moderation of genetic influence on test scores, suggesting that articulating gene-environment interactions for cognition is more complex and elusive than previously supposed.

From the paper. Note SS/OS = Same/Opposite Sex, SES = Socio-Economic Status.

First, Turkheimer and Horn indicate that “the between-pair variance of MZ pairs decreases in poor environments” (ref. 21, p. 63). Contrary to this relationship, we found that the between-pair variance of SS twins is actually lowest in the highest SES families. Given that SS twins are a relatively equal combination of MZ and DZ twins, one possibility is that a pattern supporting the hypothesis among MZ SS twins is masked by an even stronger pattern in the opposite direction among DZ SS twins. However, Fig. 3 shows that corresponding results for OS twins (all of whom are DZ) give no indication of such a pattern. Between-pair variances in achievement test scores for high-school educated parents of OS twins are higher in all cases than it is for parents without a high school diploma.

Second, Turkheimer and Horn report that “the within-pair variance of MZ twin pairs increases at lower levels of SES: poverty appears to have the effect of making MZ twins more different from each other” (ref. 21, p. 61). We would therefore expect in our data that the within-pair variance for SS twins whose mother did not graduate from high school would be higher than the variance for SS twins whose mother has a high school diploma. However, this is not the case in any of the SS twin comparisons shown in Fig. 3.

Via SSC -- thanks, Scott!

Added remarks about context and broader implications: This paper does not exclude SES effects on intelligence. Rather, it excludes a hypothesis (big nonlinear effect at low SES; GxE!) that has been widely discussed: In good environments individuals can achieve their full genetic potential, and consequently measured heritability is high. However, in bad environments individuals don't achieve their full genetic potential, and (perhaps) do not even realize the full effect of beneficial genetic variants, so heritability is much reduced. This reasonable sounding hypothesis is not supported by the Florida data, suggesting that genetic influence is similarly strong in both high and low SES families.

Now, just how strong is this genetic influence? Many large studies have been conducted on populations of twins (raised together and apart), adoptees (who end up resembling their biological parents much more than the adoptive parents who raised them), and ordinary siblings. The results suggest very high heritability of adult intelligence -- broad sense heritability may be as high as ~0.8!

Wikipedia: Recent twin and adoption studies suggest that while the effect of the shared family environment is substantial in early childhood, it becomes quite small by late adolescence. These findings suggest that differences in the life styles of families whatever their importance may be for many aspects of children's lives make little long-term difference for the skills measured by intelligence tests.

Greg Cochran on James Miller's Future Strategist podcast

James Miller interviews Greg Cochran on a variety of topics.

Some comments on the early part of the interview (you might need to listen to it to make sense of what I write below):

1. The prediction I've made about the consequences of additive genetic variance in intelligence is not that we'll be able to realize +30 SDs of cognitive ability. That would only be true if we could ignore pleiotropy, nonlinear corrections to the additive approximation, etc. What I claim is that because there are +30 SDs up for grabs in the first order approximation, it seems likely that at least a chunk of this will be realizable, leading to geniuses beyond those that have existed so far in human history (this is the actual claim). To doubt this conclusion one would have to argue that even, say, +8 or +10 SDs out of 30 are unrealizable, which is hard to believe since we have examples of healthy and robust individuals who are in the +6 or +7 range. (These numbers are poorly defined since the normal distribution fails to apply in the tails.)

### I could make further, more technical, arguments that originate from the fact that the genomic space is very high dimensional. These suggest that, given healthy/robust examples at +X, it is very unlikely that there is NO path in the high dimensional space to a phenotype value greater than X while holding "robustness" relatively fixed. ###

2. Greg comments on whether super smart people can have "normal" personalities. This is obviously not necessary for them to be viable contributors to civilization (and even less of an issue in a future civilization where everyone is quite a bit smarter on average). He posits that von Neumann might have been radically strange, but able to emulate an ordinary person when necessary. (The joke is that he was actually a Martian pretending to be human.) My impression from reading Ulam's autobiography, Adventures of a Mathematician (see also here), is that von Neumann was actually not that strange by the standards of mathematicians -- he was sociable, had a good sense of humor, enjoyed interactions with others and with his family. He and Ulam were close and spent a lot of time together. I suspect Ulam's portrait of vN is reasonably accurate.

3. The University of Chicago conference on genetics and behavior Greg mentions, which was hosted in James Heckman's institute, is described here, here, and here (videos).


### A masochist in the comments asked for the actual argument, so here it is: ###

Here's a simple example which I think conveys the basic idea.

Suppose you have 10k variants and that individuals with 5.5k or more + variants are at the limit of cognitive ability yet seen in history (i.e., at the one in a million or billion or whatever level). Now suppose that each of the 10k + variants comes with some deleterious effect on some other trait(s) like general health, mental stability, etc. (This is actually too pessimistic -- some will actually come with positive effects!) These deleterious effects are not uniform over the 10k variants -- for some fixed number of + variants (i.e., 5.5k) there are many different individuals with different levels of overall health/robustness.

Let the number of distinct genotypes that lead to (nearly) "maximal historical" cognitive ability be n = (number of ways to distribute 5.5k +'s over 10k variants); this is a huge number. Now, we know of many actual examples of historical geniuses who were relatively healthy and robust. The probability that these specific individuals achieved the *minimum* level of negative or deleterious effects over all n possibilities is vanishingly small. But that means that there are genotypes with *more* than 5.5k + variants at the same level of general robustness. These correspond to individuals who are healthy/robust but have greater cognitive ability than any historical genius.

You can make this argument fully realistic by dropping the assumption that + effect sizes on cognitive ability are uniform, that effects on different traits are completely additive, etc. The point is that there are so many genotypes that realize [cognitive ability ~ historical max], that the ones produced so far are unlikely to maximize overall health/robustness given that constraint. But that means there are other genotypes (off the surface of constraint) with even higher cognitive ability, yet still healthy and robust.

Earnings effects of personality, education and IQ for the gifted

Thanks to a reader for pointing me to this recent paper by Heckman and collaborators, which makes use of data from the Terman study of gifted individuals (minimum IQ of 135 on the Stanford-Binet).

Of the personality factors, Conscientiousness and Extraversion had the largest (positive) effect on lifetime earnings: the most conscientious or extraverted individuals earned, on average, about 50% more than the least (see figures below). See here for more on Big 5 personality factors and a link to a personality test.

The Effects of Education, Personality, and IQ on Earnings of High-Ability Men

This paper estimates the internal rate of return (IRR) to education for men and women of the Terman sample, a 70-year long prospective cohort study of high-ability individuals. The Terman data is unique in that it not only provides full working-life earnings histories of the participants, but it also includes detailed profiles of each subject, including IQ and measures of latent personality traits. Having information on latent personality traits is significant as it allows us to measure the importance of personality on educational attainment and lifetime earnings.

Our analysis addresses two problems of the literature on returns to education: First, we establish causality of the treatment effect of education on earnings by implementing generalized matching on a full set of observable individual characteristics and unobserved personality traits. Second, since we observe lifetime earnings data, our estimates of the IRR are direct and do not depend on the assumptions that are usually made in order to justify the interpretation of regression coefficients as rates of return.

For the males, the returns to education beyond high school are sizeable. For example, the IRR for obtaining a bachelor's degree over a high school diploma is 11.1%, and for a doctoral degree over a bachelor's degree it is 6.7%. These results are unique because they highlight the returns to high-ability and high-education individuals, who are not well-represented in regular data sets.

Our results highlight the importance of personality and intelligence on our outcome variables. We find that personality traits similar to the Big Five personality traits are significant factors that help determine educational attainment and lifetime earnings. Even holding the level of education constant, measures of personality traits have significant effects on earnings. Similarly, IQ is rewarded in the labor market, independently of education. Most of the effect of personality and IQ on life-time earnings arise late in life, during the prime working years. Therefore, estimates from samples with shorter durations underestimate the treatment effects.

Here are a couple of interesting excerpts from the paper:

... Our third contribution is to show how the effect of personality on earnings varies through-out the men’s working lives. We find that without access to long follow-up data, the estimated effect would be understated. Note that even though the Terman sample has a restricted range of IQ, there is substantial variation in personality. In fact, the Terman men do not differ from the general population in terms of personality.

... note that even when controlling for rich background variables, IQ maintains a statistically significant effect on lifetime earnings. Even though the effect is slightly diminished from the un-controlled association of the first column, it is still sizable. Malcolm Gladwell claims rather generally in his book Outliers that for the Terman men, IQ did not matter once family background and other observable personal characteristics were taken into account. While we do not want to argue that IQ has a larger role for the difference between 50 and 100, for example, than for the difference between 150 and 200, we do want to point out that even at the high end of the ability distribution, IQ has meaningful consequences. [The syntax of this last sentence is strange. Presumably the impact of IQ variation from 50 to 100 (from severely handicapped to average) is larger than for 150 to 200, even though their results show a significant effect even in the very high range.]

Below are some nice figures (click for larger versions). Note the personality factor distribution among Termites was similar to that of the overall population, whereas the IQ range was restricted due to selection. Typical lifetime earnings for this group of exceptionally able men ranged from $2 to $3 million in 2008 dollars.




Compare the bottom right IQ graph with SMPY results which show the impact of ability (SAT-M measured before age 13) on publication and patent rates. Ability in the SMPY graph varies between 99th and 99.99th percentile in quartiles Q1-Q4. The variation in IQ between the bottom and top deciles of the Terman study covers a similar range. The Terman super-smarties (i.e., +4 SD) only earned slightly more (say, 15-20% over a lifetime) than the ordinary smarties (i.e., +2.5 SD), but the probability of earning a patent (SMPY) went up by about 4x over the corresponding ability range.

Greg Clark: Genetics and Social Mobility — Manifold Episode #14

 

Gregory Clark is Distinguished Professor of Economics at UC-Davis. He is an editor of the European Review of Economic History, chair of the steering committee of the All-UC Group in Economic History, and a Research Associate of the Center for Poverty Research at Davis. He was educated at Cambridge University and received a PhD from Harvard University. His areas of research are long-term economic growth, the wealth of nations, economic history, and social mobility. 

Steve and Greg discuss: 

0:00 Introduction 

2:31 Background in economics and genetics 

10:25 The role of genetics in determining social outcomes 

16:27 Measuring social status through marriage and occupation 

36:15 Assortative mating and the industrial revolution 

49:38 Criticisms of empirical data, engagement on genetics and economic history 

1:12:12 Heckman and Landerso study of social mobility in US vs Denmark 

1:24:32 Predicting cognitive traits 

1:33:26 Assortative mating and increase in population variance 

Links: 

For Whom the Bell Curve Tolls: A Lineage of 400,000 English Individuals 1750-2020 shows Genetics Determines most Social Outcomes http://faculty.econ.ucdavis.edu/faculty/gclark/ClarkGlasgow2021.pdf 

Further discussion: https://infoproc.blogspot.com/2021/03/genetic-correlation-of-social-outcomes.html 

A Farewell to Alms: A Brief Economic History of the World https://en.wikipedia.org/wiki/A_Farewell_to_Alms 

The Son Also Rises https://en.wikipedia.org/wiki/The_Son_Also_Rises_(book)

Transcript.

The Chicago School and the financial crisis

New Yorker economics correspondent John Cassidy has a very balanced piece about the impact of the credit crisis on thinking at The Chicago School. He also uses the term apostasy to describe Posner's turn toward Keynes.

In the article, Heckman, Becker and Rajan seem the most reasonable. Fama is obviously clinging to his priors and Lucas refused to talk to Cassidy.

Cassidy makes additional remarks on his blog, and promises in the near future to publish more detailed notes on the interviews he did with the Chicago economists.

... For people interested in the subject, and there seems to be a lot of you, the good news is that I’m planning on posting here much fuller versions of the interviews I did in Chicago, with the likes of Gene Fama, Gary Becker, and Richard Posner, who recently converted to Keynesianism. It’s the nature of long-form magazine journalism that a lot of interesting stuff gets left out of the finished article, but, thanks to the Web, there’s no reason it shouldn’t appear in some form. Plus, I think it’s a good time to let the Chicago economists speak for themselves. Over the last couple of years, they have taken a battering at the hands of myself, Paul Krugman, Joe Stiglitz, and others. Having just finished writing a book entitled “How Markets Fail,” I went to the Windy City eager to learn first hand how the critiques of Chicago economics were being received. Some of what I was told, I don’t agree with, but at this time of intellectual tumult I think it makes fascinating reading.

In the article Posner notes that few economists knew anything about how real financial markets work. This is certainly true in my experience. In particular, they were naive about individual incentives within the system (see Greenspan comments), and very few academics (with perhaps one or two exceptions; video) had any idea what a CDO or CDS was before 2008. I can't resist a little sniping here. If you want to ask someone about electrons, or how to build a quantum logic gate, or how to fabricate nanostructures, you can't do much better than to head to your local research university and talk to a physics professor. Strangely, if I wanted to learn something about credit markets or securitization or the risk from speculative bubbles, I would have been better off talking to a former physicist on Wall St. than to almost any professor in an economics department or business school. I'm not exaggerating -- I've done both many times. Posner also says:

"Well, one possibility is that they [the economists] have learned nothing [from the financial crisis] ... Because -- how should I put it -- because market correctives work very slowly in dealing with academic markets. Professors have tenure. ... It takes a great deal to drive them out of their accustomed way of doing business."

For more, see my talk on the financial crisis.

Sweet Tweet Treats

For mysterious reasons, this old tweet has attracted almost 200k impressions in the last day or so:

Nature, Nurture, and Invention: analysis of patent, SES, IQ data from Finland. "IQ matters more than all family background variables combined" ... "IQ direct effect ... almost five times as large as that of having a high-income father"https://t.co/O6txxW4tTL pic.twitter.com/YN8EWzWqcZ

— steve hsu (@hsu_steve) December 13, 2017

If you like that tweet, this one might be of interest as well:

Low SES does not decrease heritability of cognitive ability (N=300k). PNAS, editor J. Heckman, 24k twins! "largest study to date... matched birth and school administrative records... no evidence of SES moderation of genetic influence on test scores..." https://t.co/KGIFiwzOrf pic.twitter.com/rHvqA1eUSa

— steve hsu (@hsu_steve) December 19, 2017

I'm always amazed that so many people have strong opinions on topics like Nature vs Nurture, How the World Works, How Civilization Advances (or does not), without having examined the evidence.

Recent Papers on Socio-Economic Status and Student Achievement: Marks and O'Connell

I received the message below from Michael O'Connell, University College Dublin, and Gary Marks, University of Melbourne. 

See also this recent post: Social and Educational Mobility: Denmark vs USA (James Heckman), and links therein. 

Dear Scholar, 

 

There is a widely-held perception that many of life’s key outcomes are fundamentally driven by people’s socio-economic status (SES). More specifically, there is a view that children’s educational attainment is largely a by-product of their familial SES. As a consequence of this pervasive paradigm, much of the energy in seeking to ameliorate or resolve poor educational attainment is based around trying to use SES as a social lever. 

However, in the six papers listed below, published between 2019-2022, evidence has been gathered demonstrating that SES is only very modestly correlated with educational attainment. Furthermore, once a child’s cognitive ability is taken into account, even the modest link between SES and attainment diminishes to slight influence. This is true of datasets drawn from international groups of young people, as well as those from the US, UK, or Ireland. Future attempts to aid and study young people experiencing difficulty with educational attainment should be built on an awareness of the limited role of SES. 

Gary N Marks   Michael O’Connell 

1. O’Connell, M. and Marks, G.N. (2022) 

Cognitive ability and conscientiousness are more important than SES for educational attainment: An analysis of the UK Millennium Cohort Study

Personality and Individual Differences, 188 

https://doi.org/10.1016/j.paid.2021.111471 

Highlights Antecedents of educational attainment of great interest Dominant paradigm focuses on SES of children. Cognitive ability and conscientiousness have stronger record in research findings. Using new UK MCS longitudinal survey data, GCSE state exam performance assessed Cognitive ability and conscientiousness explained far more than SES measures 

 

2. Marks, G. N. (2021) 

Is the relationship between socioeconomic status (SES) and student achievement causal? Considering student and parent abilities

Educational Research and Evaluation, 10.1080/13803611.2021.1968442: 1-24. 

Abstract Most studies on the relationship between students’ socioeconomic status (SES) and student achievement assume that its effects are sizable and causal. A large variety of theoretical explanations have been proposed. However, the SES–achievement association may reflect, to some extent, the inter-relationships of parents’ abilities, SES, children’s abilities, and student achievement. The purpose of this study is to quantify the role of SES vis-à-vis child and parents’ abilities, and prior achievement. Analyses of a covariance matrix that includes supplementary correlations for fathers and mothers’ abilities derived from the literature indicate that more than half of the SES–achievement association can be accounted for by parents’ abilities. SES coefficients decline further with the addition of child’s abilities. With the addition of prior achievement, the SES coefficients are trivial implying that SES has little or no contemporaneous effects. These findings are not compatible with standard theoretical explanations for SES inequalities in achievement. 

 

3. Marks, G. N. and O’Connell, M. (2021) 

No Evidence for Cumulating Socioeconomic Advantage. Ability Explains Increasing SES Effects with Age on Children’s Domain Test scores 

Intelligence, 88    

https://doi.org/10.1016/j.intell.2021.101582 

Highlights Data analysed for five domains for children of the NLSY79 mothers study. SES effects increase for only some domains and not substantially. No increase in SES effects when considering mother's or children's prior ability. Effects of child's prior ability on test scores increase substantially with age. SES effects are small net of mother's ability. 

 

4. Marks, G. N. and O'Connell, M. (2021) 

Inadequacies in the SES–Achievement model: Evidence from PISA and other studies 

Review of Education, 9(3): e3293. 

https://doi.org/10.1002/rev3.3293 

Abstract Students’ socioeconomic status (SES) is central to much research and policy deliberation on educational inequalities. However, the SES model is under severe stress for several reasons. SES is an ill-defined concept, unlike parental education or family income. SES measures are frequently based on proxy reports from students; these are generally unreliable, sometimes endogenous to student achievement, only low to moderately intercorrelated, and exhibit low comparability across countries and over time. There are many explanations for SES inequalities in education, none of which achieves consensus among research and policy communities. SES has only moderate effects on student achievement, and its effects are especially weak when considering prior achievement, an important and relevant predictor. SES effects are substantially reduced when considering parent ability, which is causally prior to family SES. The alternative cognitive ability/genetic transmission model has far greater explanatory power; it provides logical and compelling explanations for a wide range of empirical findings from student achievement studies. The inadequacies of the SES model are hindering knowledge accumulation about student performance and the development of successful policies. 

 

5. O'Connell, M. and Marks, G. N. (2021) 

Are the effects of intelligence on student achievement and well-being largely functions of family income and social class? Evidence from a longitudinal study of Irish adolescents

Intelligence, 84: 101511. 10.1016/j.intell.2020.101511 

Highlights Power of cognitive ability and social class contrasted. Large representative sample from longitudinal study, waves 1–3, of 6216 children Outcomes were attainments, difficulties and relationships. Cognitive ability explained large amounts of variance. Social background only minor effects 

 

6. O'Connell, M. (2019) 

Is the impact of SES on educational performance overestimated? Evidence from the PISA survey 

Intelligence, 75: 41-47 

https://doi.org/10.1016/j.intell.2019.04.005 

Highlights Policy-makers overly attribute differences in educational performance to SES. PISA survey used to assess roles of parental education and household income. Combining them concealed differences in outcomes between rich and poor countries. Household income important in poor countries, parental education in rich countries.

Becoming a behaviorialist

Becoming a behaviorialist (i.e., overcoming autism in economics ;-). Audio interview.

Leading behavioral economist Richard Thaler, the Ralph and Dorothy Keller Distinguished Service Professor of Behavioral Science and Economics, talks about how he found his way into this then-nonexistent field and how he came to study irrational economic behavior at UChicago, the home of efficient markets and rational expectations.

Lots of other good interviews in this Chicago series (iTunes): Heckman, Sargent on the euro, Hansen on risk.