Follow the science, ditch income supplements, pre-k, and income inequality initiatives

With some frequency I see claims in my neighborhood NextDoor that either poverty causes crime or that inequality causes crime.  It is a high income neighborhood with likely close to 100% with at least college education attainment.  Mostly white but with a solid salt and peppering of immigrants.  Overwhelmingly Democrat.

The distal belief that poverty and/or inequality are the core drivers of crime is widely shared.  Yet not only are the ideas unproven, the majority of evidence seems to disprove it.  Everyone is making essentially an unproven causal claim arising from an ideological interpretation or worldview and treating it as if it were a proven fact.

The other day, someone posted a link to The source of violent crime in Atlanta isn’t mysterious: It’s desperation, born by inequality. We just need to be willing to see it. by George Chidi.  

The poster's comment was "Crime in Atlanta. Great article by George Chidi. It's a long read but may be enlightening about where crime is happening, to whom, and why."

I replied as politely as I could.

Some good points in the article but primarily full of anecdotes, ideological convictions, arguments by assertion, and emotional argument.

His thesis is that crime is driven by inequality (URLs are great for distilling arguments from several thousand words to five or ten).  Three facts undermine his position.

Fact 1 - All countries which experience increased prosperity (income) also experience increased inequality.  Whether avowedly free market (USA), more socialist (Britain in the 70's, Scandinavia till the 90s), or communist (China 1990-2022).  Increased prosperity is inextricably linked to increased inequality.  

No one has found a way to increase national prosperity AND increase income equality.  While the US has more nominal inequality (there is much debate as to whether GINI is a useful measure) than other countries, it is also dramatically more prosperous than every other medium or large sized country.  You would expect us to have more inequality.

Fact 2 - Income inequality in Atlanta, Georgia and the US has been gradually and steadily increasing since 1945.  Crime is much more volatile and unrelated to inequality.  Crime was low from 1945 to 1965.  A huge increase from 1965 to a peak circa 1990-5.  Crime has been in dramatic decline since then with two exceptions.  In 2015 and 2020 (post-Ferguson and post-Floyd) and primarily located in major cities, crime did increase.  In most those cities, crime reverted to a downward trend after 2015.  Depending on public policies vis-a-vis policing, we will likely see that happen again after 2022.  

If inequality causes crime, then the two charts (crime and inequality) ought to at least be somewhat correlated.  They are not.  There are clearly other factors at play.

Fact 3 - Inequality is a relative measure and the more important issue is absolute measures.  The poorest quintile of income earners in modern economies such as the US typically have higher real incomes than low-crime middle quintiles in poorer countries.  The poorest quintile of income earners in the US today have real income consumption levels materially higher than middle income quintile earners in the US in 1950 (a period of low crime).  (See Steven Pinker, Enlightenment Now and The Better Angels of Our Nature)

Contra this article, crime is only very weakly related to income inequality.  It is much more strongly related to law enforcement policies, social breakdown, and social disruptions (whether short term disruptions such as riots or recessions, or longer term disruptions such as personal circumstance instability).  

Addressing human capital issues (values, behaviors, skills, etc.) for the bottom quintile; providing social stability, safety and security (policing); creating an economic environment of growth - these are the policies which will make the best and most difference for the bottom quintile.  Focusing on inequality achieves nothing.

Others agreed.  In an apparent fit of pique, the original poster closed the discussion.  Open forums are valued by some for the opportunity to broadcast dearly held opinions and by others are valued as a forum for discussion and evidence presentation.  Their interests are at variance and the Venn diagram intersection is relatively tiny.

There was a new paper out earlier this week which I have seen just about everyone in the Classical Liberal or rationalist communities seize and shake about like a terrier with a rat.  From The impact of a poverty reduction intervention on infant brain activity by Sonya V. Troller-Renfreea, et al.  

Early childhood poverty is a risk factor for lower school achievement, reduced earnings, and poorer health, and has been associated with differences in brain structure and function. Whether poverty causes differences in neurodevelopment, or is merely associated with factors that cause such differences, remains unclear. Here, we report estimates of the causal impact of a poverty reduction intervention on brain activity in the first year of life. We draw data from a subsample of the Baby’s First Years study, which recruited 1,000 diverse low income mother–infant dyads. Shortly after giving birth, mothers were randomized to receive either a large or nominal monthly unconditional cash gift. Infant brain activity was assessed at approximately 1 y of age in the child’s home, using resting electroencephalography (EEG; n = 435). We hypothesized that infants in the high-cash gift group would have greater EEG power in the mid- to high-frequency bands and reduced power in a low-frequency band compared with infants in the low-cash gift group. Indeed, infants in the high-cash gift group showed more power in high-frequency bands. Effect sizes were similar in magnitude to many scalable education interventions, although the significance of estimates varied with the analytic specification. In sum, using a rigorous randomized design, we provide evidence that giving monthly unconditional cash transfers to mothers experiencing poverty in the first year of their children’s lives may change infant brain activity. Such changes reflect neuroplasticity and environmental adaptation and display a pattern that has been associated with the development of subsequent cognitive skills.

The report was picked up and trumpeted in the mainstream media such as the New York Times with Cash Aid to Poor Mothers Increases Brain Activity in Babies, Study Finds.  Stuart Ritchie, who wrote the book on badly designed and misrepresented research, had a thorough critique as did numerous others.  

That giving cash to poor people will make their lives much more like those of the middle class is a distal belief of the progressive left.  It doesn't matter how little evidence there is to support the belief.  

Scott Alexander pulled much of the criticism together in a single place, Against That Poverty And Infant EEGs Study.

Before we start: why be suspicious of this paper? Hundreds of studies come out daily, we don't have enough time to nitpick all of them. Why this one? For me, it's because it's a shared environmental effect being measured by EEG at the intersection of poverty and cognition.

Shared environmental effects on cognition are notoriously hard to find. Twin studies suggest they are rare. Some people have countered that perhaps the twin studies haven't measured poor enough people, and there's a lot of research being done to see what happens if you try to correct for that, but so far it’s still controversial.

All that research is being done by cognitive testing, which is a reasonable way to measure cognition. This study uses EEG instead. I'm skeptical of social science studies that use neuroimaging, and although EEG isn't exactly the same as neuroimaging like CT or MRI, it shares a similar issue: you have to figure out how to convert a multi-dimensional result (in this case, a squiggly line on a piece of paper) into a single number that you can do statistics to. This offers a lot of degrees of freedom, which researchers don't always use responsibly.

[snip]

And finally, people want to discover a link between poverty and cognitive function so bad. Every few months, another study demonstrates that poverty decreases cognitive function, it's front page news everywhere, and then it turns out to be flawed. This recent analysis tried to replicate twenty poverty/cognition priming studies. 18/20 replications had lower effect sizes than in the original, and 16/20 had effect sizes statistically indistinguishable from zero. Most of these studies were vastly worse than the current paper - they were trying to do dumb things with priming as opposed to this much smarter thing with actual RCTs of childhood environment. Still, this whole field makes me nervous.

But Alexanders's point is somewhat broader.  The study found no effect despite how the researchers wrote it up and no matter how the mainstream presented it.  There is no there.

But this study basically shows no effect. We can quibble on whether it might be suggestive of effects, or whether it was merely thwarted from showing an effect by its low power, but it’s basically a typical null-result-having study. The authors should not have reported their result as an unqualified positive, and the media should have challenged their decision to do so rather than uncritically signal-boosting it.

Indeed.  There is no there for most of these dearly held, deeply desired belief systems.  Some people want poverty to be the cause of bad neurological outcomes and inequality to cause crime.  And pre-K to improve life outcomes.  

And the data just isn't there.  See Shovel More Dirt on Pre-K by Freddie deBoer.  It was bad enough when pre-k studies were showing that pre-k did not improve school outcomes.  In the past few years, more and more of them are showing that pre-k programs actually make things a little bit worse.  

And yet, in all cases, we keep shoveling money into these beliefs, even when they cause bad outcomes.  There are better ways to solve these social problems and betters ways to spend that wasted money.