I’m with Arnold here. The one thing that Chetty said on Econtalk that gives me pause, though, is that there is a “dosage” effect such that if parents move to a better neighborhood, it affects younger children more than older children. I’ve been trying to think of how selection could drive that finding.
It's not science if critics can't see the data to test his claims against obvious conflicts with common sense. The data is not just not public, apparently the number of people with access can be counted with two hands. At least appoint an anonymous devil's advocate defense attorney motivated to do his best to poke holes in the analysis. Absent that, it's reasonable to presume the government trusts him to publish the desired results.
Michael Porter and Peter Theil have both emphasized the importance of monopoly-like advantages and scenarios for business success, otherwise no profits over the market rate of return. Well, same goes for science, there's a lot of competition that's hard to beat. But it sure helps if you've got a permanent monopoly on the data.
Impulse control is part of what psychologists call "executive function", which is known to be almost entirely genetic. Based on that, we can discard most hypotheses that involve other factors*, such as friendships or socioeconomic status, having significant effects on impulse control
Compare two recents studies by John A. List and colleagues. (Note: What List et al. call non-cognitive traits includes, among other things, impulse control.):
1) "The Social Side of Early Human Capital Formation: Using Field Experiment to Estimate
the Causal Impact of Neighborhoods" (December 2020):
"This study leverages insights from sociology to explore the role of neighborhoods on human capital formation at an early age. We do so by estimating the spillover effects from a large-scale early childhood intervention on the educational attainment of over 2,000 disadvantaged children in the US. We document large spillover effects on both treatment and control children who live near treated children. [...] spillover effects are localized, decreasing with the spatial distance to treated neighbors. Perhaps our most novel insight is the underlying mechanisms at work: the spillover effect on non-cognitive scores operate through the child's social network while parental investment is an important channel through which cognitive spillover effects operate." (Abstract)
"We find that non-cognitive spillover effects are significantly larger for Blacks than Hispanics. [... .] African American adolescents are significantly more likely than Hispanics to (i) know most people in their neighborhoods, (ii) stop on the street and talk to someone from the neighborhood, and (iii) use recreation facilities in the neighborhood." (pp. 4 & 5)
" [...] non-cognitive spillover effects are more likely to operate through children’s rather than parents’ social networks." (p. 4)
2) "How Experiments with Children Inform Economics" (May 2021):
"[...] skills and economic preferences result from a nature-nurture (i.e., gene-environment) interaction. In our framework, children are born with a 'band' of potential skills or preferences, and the level expressed within that band depends on the environment, including parenting or interventions. [... .] genes explain some - but not all - of the variation in economic preferences and outcomes " (pp. 10-11)
"[...] the effects of a parenting program were most concentrated among students with high executive function skills at baseline" (p. 14)
"There is some evidence for 'reversion to the mean' in the sense that many early childhood interventions see fade-out of skills learned in the years following a program" (p. 14)
"[...] there is some evidence that [cognitive and non-cognitive] skills move in tandem" (p. 15)
"[...] a review of data from interventions targeted at various age groups have shown benefit-cost ratios that decline with the age of the targeted group" (p. 15)
"[...] low-SES parents are less likely to believe that their investments in their baby can affect brain development as compared to higher-income and higher-educational attainment parents." (p. 16)
"Children who believe they can change their intelligence (growth mindset) achieve more than children who believe that they cannot do so (fixed mindset)" (p. 16)
"[...] time preferences measured at age 3-5 are associated with disciplinary referrals years later in elementary school. Importantly, these preferences are distinct from cognitive skills (e.g., reading, writing, math) and executive functions (e.g., inhibitory control and working memory) in that they have an independent role in predicting disciplinary referrals." (p. 26)
"[...] time and risk preferences measured in adolescence are correlated with educational and labor market outcomes later in life." (p. 29)
One context where I think there is likely to be a causal effect to different SES people mixing together also happens to connect to your impulse control objection.
Consider the LDS communities in Utah, which score quite well for upward mobility in Chetty’s data. In the church community, poor people receive a lot more direct attention and assistance from rich people than in other settings, in terms of money, time, and free counseling. Mitt Romney essentially had a part time volunteer job helping struggling Mormons on the side of his career in the private sector. Now what happens when Mitt Romney meets a young member of his ward who is poor and aimless, but also very bright and capable? I suspect he makes a big effort to connect him to a job or schooling opportunity that will point him in the right direction. I’m sure this has a meaningful effect, and have indeed met several people like this who were helped by less famous versions of Mitt.
Won’t LDS communities select on impulse control? Surely to some extent, since standards of abstinence from alcohol and pre-marital sex are harder to fully keep without it. But many people who struggle with these things also select into the church and I think they benefit from it. Even if we suppose that only the higher impulse control individuals see the persistent, meaningful gains I think that there is a lot more value than most people realize to having high status people around to encourage and recognize talent. Many people would not accomplish nearly as much without that experience.
I wish Chetty would emphasize this connection to religion more explicitly when he talks to the New York Times (he did in his CWT), since I don’t think just living in the vicinity of rich people does very much. But despite partly agreeing with objections made by yourself and Jim Heckman, I think there’s a causal effect of some sort here, not just selection.
Well obviously. I very much doubt that it was Chetty's hypothesis that it was the wealth per se that caused the increase in positive outcomes of the children. But rather some basket of other attributes that the wealth either caused, or which are correlated with wealth. I mean obviously these young children are not running around spending mommy and daddy's money. There are other factors at work here
Depending on the cost and difficulty, trying to promote less class segregation in education is probably still a good idea. My Bayesian prior of effectiveness is not zero.
An obvious factor for friendship among children is sports and activities. How many poor kids play lacrosse? Hockey? The equipment cost is prohibitive. How many rich kids play football now? Soccer and basketball probably have a mix of players, but the leagues are different. Travel teams and clubs are costly in time and money. Activities like scouting are now mostly rich kids. My son has enrolled in the Russian School of Math since 3 (he likes it), not many poor kids there. How many poor kids ski? Summer camps are definitely divided by class. Not many poor kids are in my son’s sailing camp. I just went to New England county fair with my son, one I used to attend as a child. As Boston resident immersed in the biotech/academic world, it was like visiting a foreign country - there were Trump flags for sale!
The obvious reason for the divide - the rich are building their children’s resume for college admission and do everything they can to differentiate them.
Isn’t that the point of the age of moving data? E.g. if you have different aged siblings that move at the same time and you can find a “dosage” effect of the move as a treatment, then it’s “a good as causal” because whatever the hidden factors, the treatment is associated with improvements. I.e. you don’t have to know what people buy with the EITC you know that it’s effective
I’m with Arnold here. The one thing that Chetty said on Econtalk that gives me pause, though, is that there is a “dosage” effect such that if parents move to a better neighborhood, it affects younger children more than older children. I’ve been trying to think of how selection could drive that finding.
Why is it where academic and economic success is studied, that above all genetics must at all costs be ignored as a major determining factor?
It's not science if critics can't see the data to test his claims against obvious conflicts with common sense. The data is not just not public, apparently the number of people with access can be counted with two hands. At least appoint an anonymous devil's advocate defense attorney motivated to do his best to poke holes in the analysis. Absent that, it's reasonable to presume the government trusts him to publish the desired results.
Michael Porter and Peter Theil have both emphasized the importance of monopoly-like advantages and scenarios for business success, otherwise no profits over the market rate of return. Well, same goes for science, there's a lot of competition that's hard to beat. But it sure helps if you've got a permanent monopoly on the data.
Impulse control is part of what psychologists call "executive function", which is known to be almost entirely genetic. Based on that, we can discard most hypotheses that involve other factors*, such as friendships or socioeconomic status, having significant effects on impulse control
See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2762790/.
*With some exceptions for rare and extreme factors (e.g. severe malnutrition or brain trauma).
Compare two recents studies by John A. List and colleagues. (Note: What List et al. call non-cognitive traits includes, among other things, impulse control.):
1) "The Social Side of Early Human Capital Formation: Using Field Experiment to Estimate
the Causal Impact of Neighborhoods" (December 2020):
https://bfi.uchicago.edu/wp-content/uploads/2021/01/BFI_WP_2020187.pdf
Excerpts:
"This study leverages insights from sociology to explore the role of neighborhoods on human capital formation at an early age. We do so by estimating the spillover effects from a large-scale early childhood intervention on the educational attainment of over 2,000 disadvantaged children in the US. We document large spillover effects on both treatment and control children who live near treated children. [...] spillover effects are localized, decreasing with the spatial distance to treated neighbors. Perhaps our most novel insight is the underlying mechanisms at work: the spillover effect on non-cognitive scores operate through the child's social network while parental investment is an important channel through which cognitive spillover effects operate." (Abstract)
"We find that non-cognitive spillover effects are significantly larger for Blacks than Hispanics. [... .] African American adolescents are significantly more likely than Hispanics to (i) know most people in their neighborhoods, (ii) stop on the street and talk to someone from the neighborhood, and (iii) use recreation facilities in the neighborhood." (pp. 4 & 5)
" [...] non-cognitive spillover effects are more likely to operate through children’s rather than parents’ social networks." (p. 4)
2) "How Experiments with Children Inform Economics" (May 2021):
https://bfi.uchicago.edu/wp-content/uploads/2021/05/BFI_WP_2021-62.pdf
Excerpts:
"[...] skills and economic preferences result from a nature-nurture (i.e., gene-environment) interaction. In our framework, children are born with a 'band' of potential skills or preferences, and the level expressed within that band depends on the environment, including parenting or interventions. [... .] genes explain some - but not all - of the variation in economic preferences and outcomes " (pp. 10-11)
"[...] the effects of a parenting program were most concentrated among students with high executive function skills at baseline" (p. 14)
"There is some evidence for 'reversion to the mean' in the sense that many early childhood interventions see fade-out of skills learned in the years following a program" (p. 14)
"[...] there is some evidence that [cognitive and non-cognitive] skills move in tandem" (p. 15)
"[...] a review of data from interventions targeted at various age groups have shown benefit-cost ratios that decline with the age of the targeted group" (p. 15)
"[...] low-SES parents are less likely to believe that their investments in their baby can affect brain development as compared to higher-income and higher-educational attainment parents." (p. 16)
"Children who believe they can change their intelligence (growth mindset) achieve more than children who believe that they cannot do so (fixed mindset)" (p. 16)
"[...] time preferences measured at age 3-5 are associated with disciplinary referrals years later in elementary school. Importantly, these preferences are distinct from cognitive skills (e.g., reading, writing, math) and executive functions (e.g., inhibitory control and working memory) in that they have an independent role in predicting disciplinary referrals." (p. 26)
"[...] time and risk preferences measured in adolescence are correlated with educational and labor market outcomes later in life." (p. 29)
One context where I think there is likely to be a causal effect to different SES people mixing together also happens to connect to your impulse control objection.
Consider the LDS communities in Utah, which score quite well for upward mobility in Chetty’s data. In the church community, poor people receive a lot more direct attention and assistance from rich people than in other settings, in terms of money, time, and free counseling. Mitt Romney essentially had a part time volunteer job helping struggling Mormons on the side of his career in the private sector. Now what happens when Mitt Romney meets a young member of his ward who is poor and aimless, but also very bright and capable? I suspect he makes a big effort to connect him to a job or schooling opportunity that will point him in the right direction. I’m sure this has a meaningful effect, and have indeed met several people like this who were helped by less famous versions of Mitt.
Won’t LDS communities select on impulse control? Surely to some extent, since standards of abstinence from alcohol and pre-marital sex are harder to fully keep without it. But many people who struggle with these things also select into the church and I think they benefit from it. Even if we suppose that only the higher impulse control individuals see the persistent, meaningful gains I think that there is a lot more value than most people realize to having high status people around to encourage and recognize talent. Many people would not accomplish nearly as much without that experience.
I wish Chetty would emphasize this connection to religion more explicitly when he talks to the New York Times (he did in his CWT), since I don’t think just living in the vicinity of rich people does very much. But despite partly agreeing with objections made by yourself and Jim Heckman, I think there’s a causal effect of some sort here, not just selection.
Someone should ask Emil Kirkegaard for possible factors like IQ and verbal tilt distorting this result of parental correlation vs environmental.
Well obviously. I very much doubt that it was Chetty's hypothesis that it was the wealth per se that caused the increase in positive outcomes of the children. But rather some basket of other attributes that the wealth either caused, or which are correlated with wealth. I mean obviously these young children are not running around spending mommy and daddy's money. There are other factors at work here
Depending on the cost and difficulty, trying to promote less class segregation in education is probably still a good idea. My Bayesian prior of effectiveness is not zero.
An obvious factor for friendship among children is sports and activities. How many poor kids play lacrosse? Hockey? The equipment cost is prohibitive. How many rich kids play football now? Soccer and basketball probably have a mix of players, but the leagues are different. Travel teams and clubs are costly in time and money. Activities like scouting are now mostly rich kids. My son has enrolled in the Russian School of Math since 3 (he likes it), not many poor kids there. How many poor kids ski? Summer camps are definitely divided by class. Not many poor kids are in my son’s sailing camp. I just went to New England county fair with my son, one I used to attend as a child. As Boston resident immersed in the biotech/academic world, it was like visiting a foreign country - there were Trump flags for sale!
The obvious reason for the divide - the rich are building their children’s resume for college admission and do everything they can to differentiate them.
Isn’t that the point of the age of moving data? E.g. if you have different aged siblings that move at the same time and you can find a “dosage” effect of the move as a treatment, then it’s “a good as causal” because whatever the hidden factors, the treatment is associated with improvements. I.e. you don’t have to know what people buy with the EITC you know that it’s effective