Category: Data Source

Claims about Chennai naps

A three-week treatment providing information, encouragement, and sleep-related items increased sleep quantity by 27 minutes per night without improving sleep quality. Increased night sleep had no detectable effects on cognition, productivity, decision-making, or psychological and physical well-being, and led to small decreases in labor supply and thus earnings. In contrast, offering high-quality naps at the workplace increased productivity, cognition, psychological well-being, and patience.

That is from a new NBER working paper by Pedro Bessone, Gautam Rao, Frank Schilbach, heather Schofield, Mattie Toma.

Reversing the STEM gender gap in Israel?

A new study compares Hebrew-speaking with some Arabic-speaking communities, here is the abstract:

In the past three decades in high‐income countries, female students have outperformed male students in most indicators of educational attainment. However, the underrepresentation of girls and women in science courses and careers, especially in physics, computer sciences, and engineering, remains persistent. What is often neglected by the vast existing literature is the role that schools, as social institutions, play in maintaining or eliminating such gender gaps. This explorative case study research compares two high schools in Israel: one Hebrew‐speaking state school that serves mostly middleclass students and exhibits a typical gender gap in physics and computer science; the other, an Arabic‐speaking state school located in a Bedouin town that serves mostly students from a lower socioeconomic background. In the Arabic‐speaking school over 50% of the students in the advanced physics and computer science classes are females. The study aims to explain this seemingly counterintuitive gender pattern with respect to participation in physics and computer science. A comparison of school policies regarding sorting and choice reveals that the two schools employ very different policies that might explain the different patterns of participation. The Hebrew‐speaking school prioritizes self‐fulfillment and “free‐choice,” while in the Arabic‐speaking school, staff are much more active in sorting and assigning students to different curricular programs. The qualitative analysis suggests that in the case of the Arabic‐speaking school the intersection between traditional and collectivist society and neoliberal pressures in the form of raising achievement benchmarks contributes to the reversal of the gender gap in physics and computer science courses.

The article is “Explaining a reverse gender gap in advanced physics and computer science course‐taking: An exploratory case study comparing Hebrew‐speaking and Arabic‐speaking high schools in Israel” by Halleli Pinson, Yariv Feniger, and Yael Barak.

Via the excellent Kevin Lewis.

The long-run effects of cholera on an urban landscape

How do geographically concentrated income shocks influence the long-run spatial distribution of poverty within a city? We examine the impact on housing prices of a cholera epidemic in one neighborhood of nineteenth century London. Ten years after the epidemic, housing prices are significantly lower just inside the catchment area of the water pump that transmitted the disease. Moreover, differences in housing prices persist over the following 160 years. We make sense of these patterns by building a model of a rental market with frictions in which poor tenants exert a negative externality on their neighbors. This showcases how a locally concentrated income shock can persistently change the tenant composition of a block.

Here is the new AER piece by Attila Ambrus, Erica Field, and Robert Gonzalez.  What might be the modern applications of this insight?

The private school experiment in Liberia

In 2016, the Liberian government delegated management of 93 randomly selected public schools to private providers. Providers received US$50 per pupil, on top of US$50 per pupil annual expenditure in control schools. After one academic year, students in out-sourced schools scored 0.18 σ higher in English and mathematics. We do not find heterogeneity in learning gains or enrollment by student characteristics, but there is significant heterogeneity across providers. While outsourcing appears to be a cost-effective way to use new resources to improve test scores, some providers engaged in unforeseen and potentially harmful behavior, complicating any assessment of welfare gains.

That is by Mauricio Romero, Justin Sandefur, and Wayne Aaron Sandholtz in the new AER.  The gains are real, and not the result of student selection.  That said costs are higher with the private contracting.  Better partner selection would have improved the program greatly, though the authors note that some of the most promising partners ex ante ended up being the biggest troublemakers ex post.  Some of the schools, for instance, allowed a possibly unacceptable degree of sexual abuse of the students.  There is perhaps potential for dynamic reoptimization of permissible partners to yield very real gains, though this may or may not be supported by the available political economy incentives.

The authors suggest, by the way, that outsourcing or contracting out to the private sector often does better when quality is relatively simple, such as with water services, food distribution, and simple forms of primary health care, such as immunization.  In their view, for advanced health care and prisons, contracting is less effective, due to the vaguer nature of product quality.

This is in any case a very important paper, likely to be one of the best and most significant of the year.

CEO ages at hire

This is a profound trend. The average age of incoming CEOs for S&P 500 companies has increased about 14 years over the last 14 years.

From 1980 to 2001 the average age of a CEO dropped four years and then from 2005 to 2019 the averare incoming age of new CEOs increased 14 years!

This means that the average birth year of a CEO has not budged since 2005. The best predictor of becoming a CEO of our most successful modern institutions?

Being a baby boomer.

Here is more from Paul Millerd.

The economist as scapegoat

Russ Roberts defends Milton Friedman (and many others, implicitly), excerpt:

What about spending for public schools? Has that been reduced in this allegedly draconian neoliberal era?

In 1960, per pupil expenditure for elementary and high school students was just under $4000. In 1980, when the neoliberal ideology allegedly began its ascendance, it was a little less than $8000. The latest numbers from 2015–2016 are just under $15,000. All numbers are corrected for inflation (in 2017–2018 dollars). So under this time of alleged cutbacks and resource starvation, per pupil expenditures rose dramatically.

What about transportation infrastructure? Total spending is up in real terms. What about as a percentage of GDP? There has been a decline since 1962 as a percentage of GDP but the numbers are basically flat since 1980…

What about investment in non-defense research and development, and health? Up dramatically since 1980 in real terms.

There is much more at the link, including excellent visuals.

Draining the swamp

From Jason Crawford, Emergent Ventures winner in Progress Studies:

…the surprising thing I found is that infectious disease mortality rates have been declining steadily since long before vaccines or antibiotics…

In 1900, the most deaths came from tuberculosis, influenza/pneumonia, and gastroenteric diseases such as dysentery. All of these were effectively conquered by antibiotics in the 1930s and ’40s, but were on the decline since at least the beginning of the century…

Indeed, digging further into the UK data from the late 1800s, we can see that TB was declining since at least 1850 and gastroenteric disease since the 1870s. And similar patterns hold for lesser killers such as measles, which didn’t have a vaccine until the 1960s, but which by then had already declined in mortality by more than 90% from its 1900 levels.

So what was going on? If you read my survey of technologies against infectious disease, you know that other than drugs and immunization, there is one other way to fight germs: cleaning up the environment.

I was surprised to learn that sanitation efforts began as early as the 1700s—and that these efforts were based on data collection and analysis, long before a full scientific theory of infection had been worked out.

There is much more at the link, including the footnotes for citations to the claims made here.

Do elections make you sick?

Yes basically, at least in Taiwan:

Anecdotal reports and small-scale studies suggest that elections are stressful, and might lead to a deterioration in voters’ mental well-being. Nonetheless, researchers have yet to establish whether elections actually make people sick, and if so, why. By applying a regression discontinuity design to administrative health care claims from Taiwan, we determine that elections increased health care use and expense only during legally specified campaign periods by as much as 19%. Overall, the treatment cost of illness caused by elections exceeded publicly reported levels of campaign expenditure, and accounted for 2% of total national health care costs during the campaign period.

That is from a new paper by Hung-Hao Chang and Chad Meyerhoefer.

Model this East German crime

Following the collapse of the communist regime in 1989, the number of births halved in East Germany. These cohorts became markedly more likely to be arrested as they grew up in reunified Germany. This is observed for both genders and all offence types.

Here is the full article by Arnauld Chevalier and Olivier Marie, the authors seem to think the reunification event selects for risky parents, are there other possible explanations?

Via the excellent Kevin Lewis.

Evidence for State Capacity Libertarianism

The plots do not support the hypothesis that small government produces either greater prosperity or greater freedom. (In reading the charts, remember that the SGOV index is constructed so that 0 indicates the largest government and 10 the smallest government.) Instead, smaller government tends to be associated with less prosperity and less freedom. Both relationships are statistically significant, with correlations of 0.43 for prosperity and 0.35 for freedom.

Using SoG, the Cato measure of size of government, instead of SGOV, the IMF measure, does not help. The correlations turn out still to be negative and statistically significant, although slightly weaker.

Let’s turn now to the alternative hypothesis that quality of government, rather than size, is what counts for prosperity and freedom. Here are those scatterplots:

This time, both relationships are positive. High quality of government is strongly associated both with greater human prosperity and greater human freedom. Furthermore, the correlations are much stronger than those for the size of government.

That is all by Ed Dolan, recommended, and by the way smaller governments are not correlated with higher quality governments.

Countering The Narrative

A surprising fact about the 2016 election is that Trump received fewer votes from whites with the highest levels of racial resentment than Romney did in 2012…Trump’s vote totals improved the most among swing voters: low-socioeconomic status whites who are political moderates.

That is from recent research by Justin Grimmer and William Marble, hat tip anonymous.

How bad are smart phones for people and kids?

The latest research, published on Friday by two psychology professors, combs through about 40 studies that have examined the link between social media use and both depression and anxiety among adolescents. That link, according to the professors, is small and inconsistent.

“There doesn’t seem to be an evidence base that would explain the level of panic and consternation around these issues,” said Candice L. Odgers, a professor at the University of California, Irvine, and the lead author of the paper, which was published in the Journal of Child Psychology and Psychiatry…

The new article by Ms. Odgers and Michaeline R. Jensen of the University of North Carolina at Greensboro comes just a few weeks after the publication of an analysis by Amy Orben, a researcher at the University of Cambridge, and shortly before the planned publication of similar work from Jeff Hancock, the founder of the Stanford Social Media Lab. Both reached similar conclusions.

“The current dominant discourse around phones and well-being is a lot of hype and a lot of fear,” Mr. Hancock said. “But if you compare the effects of your phone to eating properly or sleeping or smoking, it’s not even close.”

Here is the full NYT piece by Nathaniel Popper.

Assessing State Capacity Libertarianism

Ryan Murphy and Colin O’Reilly suddenly have a 33 pp. (yes substantive) paper on my January 1 blog post on State Capacity Libertarianism (on speed, perhaps they have learned from a master).  Here is the abstract:

Cowen (2020) argues for a redirection of effort towards “State Capacity Libertarianism,” which keeps the core of policy proposals from libertarianism intact while emphasizing a select set of policies aimed at furthering economic growth. These policies center on the ability of the state to accomplish that which it sets out to accomplish, i.e. state capacity. This paper interprets Cowen’s proposal in terms of an interaction between economic freedom and state capacity. Using four measures of state capacity, it finds that state capacity and economic freedom are neither additive nor complementary. Rather, they are substitutes for one another. These results are uncomfortable for conventional libertarianism, for the advocates of state capacity, and for State Capacity Libertarianism itself. One measure of state capacity we use is a novel measure using data from the Varieties of Democracy dataset, which may be useful for researchers in other contexts.

I am very pleased (and flattered) they undertook this investigation.  In terms of response on the particulars, I would say that State Capacity Libertarianism is about living standard levels, not marginal growth rates holding per capita income constant (as they do), which tends to drain off the benefits of state capacity.  You can run into similar misspecification problems by regressing against growth rates for the particular American states, whereas again the levels ought to be central to the analysis.  I readily admit the levels are not easy to handle econometrically, mostly because (outside of some oil principalities) “all good things go together,” and the correct causal model is not well understood.

In any case, the debate will go on.

How economics has changed

Panel A illustrates a virtually linear rise in the fraction of papers, in both the NBER and top-five series, which make explicit reference to identification.  This fraction has risen from around 4 percent to 50 percent of papers.


Currently, over 40 percent of NBER papers and about 35 percent of top-five papers make reference to randomized controlled trials (RCTs), lab experiments, difference-in-differences, regression discontinuity, event studies, or bunching…The term Big Data suddenly sky-rockets after 2012, with a more recent uptick in the top five.

Note that about one-quarter of NBER working papers in applied micro make references to difference-in differences. And:

The importance of figures relative to tables has increased substantially over time…

And about five percent of top five papers were RCTs in 2019.  Note also that “structural models” have been on the decline in Labor Economics, but on the rise in Public Economics and Industrial Organization.

That is all from a recent paper by Janet Currie, Henrik Kleven, and Esmee Zwiers, “Technology and Big Data are Changing Economics: Mining Text to Track Methods.”

Via Ilya Novak.

Is there a happiness cost to being too patient?

We find that excessive patience is costly for individual well-being. This result is consistent across nine different measures of subjective well-being. Our measure of patience varies from a minimum of -1.31 to a maximum of 2.76 (this measure has standardized mean of zero and standard deviation of 1). For one of the main well-being indices, the life evaluation index, the level of patience that maximizes happiness is equal to 1.56, a numerical value similar to the one obtained using other well-being indicators.


…moving from a level of patience of 1.40 corresponding to the peak in the positive experience index to the 99thpercentile in patience reduces the positive experienced index by 1.07, equivalent to 26% of the difference in happiness between those who completed college (7.16) and those with a high school diploma (3.12).

Contrary to how the language of the authors might be interpreted, this is a correlation rather than an established relationship.

The 13 pp. paper by Paola Giuliano and Paola Sapienza is too short, but interesting nonetheless.  I also would like to see a study on how the patience of parents affects the happiness of their children and grandchildren.