Month: January 2019

Greek life isn’t as good as you thought

Using records from a large public university, we examine the impact of Greek life on academic performance and salaries. To isolate the causal effect of Greek life, we exploit a university policy prohibiting students from joining a Greek organization during their first semester and a minimum GPA for subsequent eligibility. Regression discontinuity and panel methods reveal that Greek affiliation reduces student grades by 0.1-0.3 standard deviations. Greek effects are largest during the semester of pledging, semesters of increased social activities, and for males. We find no evidence of a Greek salary premium and rule out even modest positive effects.

That is from a new paper by William E. Even and Austin C. Smith, being presented at the AEa meetings this week.

Saturday assorted links

Do longer sentences reduce crime?

I find that Republican prosecutorial offices sentence defendants to longer incarceration spells as compared to their Democratic and Independent counterparts. This increase in incarceration length is driven by longer sentences for both violent and prop- erty offenses, and translates into a persistent increase in incarceration. These sentencing and incarceration enhancements do not lower crime at the county level, indicating that, in terms of public safety, the marginal return to the tough-on-crime stance may be close to zero.

That is from a new AEA paper by Ashna Arora.

The Economic Motives for Foot-Binding

From Lingwei Wu and Xinyu Fan at AEA:

What are the origins of gender-biased social norms? As a painful custom that persisted in historical China, foot-binding targeted girls whose feet were reshaped during early childhood. This paper presents a unified theory to explain the stylized facts of foot-binding, and investigates its historical dynamics driven by a gender-asymmetric mobility system in historical China (the Civil Examination System). The exam system marked the transition from hereditary aristocracy to meritocracy, generated a more heterogeneous composition of men compared to that of women, and triggered intensive competition among women in the marriage market. As a competition package carrying both aesthetic and moral values, foot-binding was gradually adopted by women as their social ladder, first in the upper class and later by the lower class. Since foot-binding impedes non-sedentary labor, but not sedentary labor, however, its adoption in the lower class exhibited distinctive regional variation: it was highly prevalent in regions where women specialized in household handicraft, and was less popular in regions where women specialized in intensive farming, e.g. rice cultivation. Empirically, we conduct analysis using county-level Republican archives on foot-binding to test the cross-sectional predictions of our theory, and major findings that are robust and consistent with key theoretical predictions.

There are other interesting papers at the link, relating to culture and women’s issues.

Hacking Photosynthesis

The vast majority of life on Earth depends, either directly or indirectly, on photosynthesis for its energy. And photosynthesis depends on an enzyme called RuBisCO, which uses carbon dioxide from the atmosphere to build sugars. So, by extension, RuBisCO may be the most important catalyst on the planet.

Unfortunately, RuBisCO is, well, terrible at its job. It might not be obvious based on the plant growth around us, but the enzyme is not especially efficient at catalyzing the carbon dioxide reaction. And, worse still, it often uses oxygen instead. This produces a useless byproduct that, if allowed to build up, will eventually shut down photosynthesis entirely. It’s estimated that crops such as wheat and rice lose anywhere from 20 to 50 percent of their growth potential due to this byproduct.

While plants have evolved ways of dealing with this byproduct, they’re not especially efficient. So a group of researchers at the University of Illinois, Urbana decided to step in and engineer a better way. The result? In field tests, the engineered plants grew up to 40 percent more mass than ones that relied on the normal pathways.

That’s John Timmer at Ars Technica summarizing a paper by South et al. in Science. The experiment was done in tobacco plants but the same pathways are used in the C3 group of plants including rice, wheat, barley, soybean, cotton and sugar beets so the applications are large.

Friday assorted links

1. “Examining explanations for the rise of in-and-outs [labor force participation], I find little evidence to suggest that changes in labor demand are responsible.”  Other interesting papers at the same link, such as: “Overall, our findings suggest that there is no simple causal relationship between economic conditions and the abuse of opioids.”  And opioids actually seem to boost labor force participation of women.

2. “…we find no evidence that mothers’ education reduces their support for FGC.”

3. “Contrary to other groups, internet searches and reported cases of arrest-related deaths have a strong negative well-being effect within the Black community that can explain up to half the Black-White [well-being] decline after 2013.

4. Profile of Elizabeth Anderson (New Yorker).

5. Arnold Kling annotates Cowen, Andreessen, and Horowitz.

6. What happened to 90s environmentalism?

7. Spiders can fly hundreds of miles using electricity.

Why private regulation of internet speech doesn’t make many people happy

That is the topic of my latest Bloomberg article, here is one excerpt:

I’d like to suggest a simple trilemma. When it comes to private platforms and speech regulation, you can choose two of three: scalability, effectiveness and consistency. You cannot have all three. Furthermore, this trilemma suggests that we — whether as users, citizens or indeed managers of the platforms themselves — won’t ever be happy with how speech is regulated on the internet.

There is much more at the link.

The Spousal Wage Boost: Working Together to Beat the Gender Wage Gap

That is another AEA paper, by Andrew Langan and Betsey Stevenson, once again abstract only:

Individuals who work in the same occupation as their spouse have significantly higher earnings on average than similar people whose spouses work in different occupations. For instance, a lawyer married to a lawyer makes more than an otherwise identical lawyer married to a physician or a teacher. The earnings effect associated with such “same-occupation marriages” is negative for less-educated men but positive for other groups and stronger for women than men. This effect holds throughout the last several decades in cross-sectional US data, and cannot be explained by hours worked, education, self-employment, or other observables.

I have not read the paper, but I wonder if this is necessarily as feminist a result as it might at first seem…

Does Cognitive Imprecision Result in Under-Reaction or Over-Reaction?

That is the topic of a new paper by Michael Woodford, to be presented at this year’s AEA meetings.  Here at least is the abstract:

Men who score high on standardized IQ tests display forecast errors for inflation that are 50% lower than forecast errors for other men in a representative sample of Finnish households. High-IQ men, but not others, have consistent inflation expectations over time and their inflation perceptions align with past expectations. Only high-IQ men increase their consumption propensity when expecting higher inflation in line with the consumption Euler equation. High-IQ men are also twice as sensitive to interest-rate changes when making borrowing decisions. Heterogeneity in education, income, or financial constraints do not explain these results. Limited cognitive abilities are thus human frictions to the transmission and effectiveness of economic policy and inform research on heterogeneous agents in macroeconomics and finance.

How many papers are there in economics about psychological cognitive bias as a source of error, as opposed to low IQ as a source of error?  Might that be a bias of sorts and not one of IQ?

The Rising Value of Time and the Origin of Urban Gentrification

By Yichen Su, here is more from the AEA meetings:

I estimate a spatial equilibrium model to show that the rising value of high-skilled workers’ time is an important driving force behind the gentrification of American central cities. I show that the increasing value of time raises the cost of commuting and exogenously increases the demand for central locations by high-skilled workers. While change in value of time is an initial force behind gentrification, its effect is substantially magnified by endogenous amenity improvement. The model implies that welfare inequality in the recent decades increases by more than the rise in earnings inequality if the forces behind gentrification are considered.

You will find other interesting papers on gentrification at this link, for instance: “We find that areas with
more gay and lesbian couples are more likely to experience gentrification.”

Thursday assorted links

Me on elitism in economics

He [Cowen] said that he agreed with the idea that influence of economics comes from a relatively small number of institutions, and he thinks the number is shrinking. “What used to be something like a ‘top six’ has over time become the ‘top two,’ namely Harvard and MIT.”

Cowen said that he doesn’t “find that entirely ideal, by any means.” But he also said that those departments deserve praise for their work. “Harvard and MIT are in fact remarkably good at finding, evaluating and attracting top talent. It is stunning how good they are at this, and we should not begrudge them that,” he said. (Cowen is an example, having earned his Ph.D. at Harvard. His undergraduate alma mater is George Mason, where he teaches.)

The centralization of top departments, he said, worries him less than do “pressures for conformity.”

Cowen added that he is sympathetic to Vigdor’s criticism, but that the centralization may be “an opportunity” for departments outside the elites to shine. “The centralized centers of influence are going to miss important ideas in their early stages,” Cowen said. “Both public choice and experimental economics came out of non-top schools,” including to some extent George Mason, he said. “So did blogging. If something is unfair, well, in part that is your big chance.”

That is from Scott Jaschik at Inside HigherEd, mostly about Jacob Vigdor and his critique of the economics profession.

The new economics of complaining

Barbara Deckert has a new weapon in the war against airplane noise — and she’s not afraid to use it.

Every time a plane flies over her suburban Maryland home, rattling her windows and setting her teeth on edge, she presses a small white button and feels a tiny sense of triumph.

That’s because with one click, Deckert has done what could have taken her hours to do a few months ago — she has filed a noise complaint with officials at the Maryland Aviation Administration.

Thanks to the ingenuity of a software engineer from Southern California, Deckert and hundreds of others with similar beefs, and the Airnoise button, have an easy way to register their annoyance with the jets that fly over their homes.

“It’s a fabulous tool,” Deckert said. “Clicking that button is really psychologically satisfying.”

Officials at airports from Seattle to Baltimore said Airnoise has led to a dramatic spike in complaints. At Baltimore-Washington International Marshall Airport, officials are almost certain Airnoise is the reason complaints surged to 17,228 in August from 2,692 the previous month. In San Diego, more than 90 percent of the complaints came through third-party apps like Airnoise.

That is from Lori Aratani at WaPo, via Eric J.  And there is this, a metaphor for our times:

The button has clearly gotten a lot of use: The plastic coating is partially peeled off. A few weeks ago, the battery gave out. So for now, she’s using her iPad to file complaints.

“People can try to discredit me, but I don’t worry about that,” she said. She paused and remembered the day she filed her first complaint with the Airnoise button.

“It felt so good,” she said. “It’s highly, highly therapeutic. It makes you feel like you can make a difference.”

Does Economics Make You Sexist?

That is the title of a new paper by Valentina Paredes, M. Daniele Paserman, and Francisco J. Pino, to be presented at the forthcoming AEA meetings:

Recent research has highlighted unequal treatment for women in academic economics along several different dimensions: promotion, hiring, credit for co-authorship, and standards for publication in professional journals. Can the source of these differences lie in biases against women that are pervasive in the discipline, even among students in the earliest stages of their training? In this paper, we provide direct evidence on the importance of explicit and implicit biases against women among students in economics relative to other fields. We conducted a large scale survey among undergraduate students in Chilean universities, among both entering first-year students and upperclassmen. The survey elicits measures of implicit bias, explicit bias, and gender attitudes. We document that, on a wide battery of measures, economics students are more biased than students in other fields. There is some evidence that economics freshmen are more biased already upon entry, before exposure to any economic classes. The gap becomes substantially more pronounced among upperclassmen, in particular for male students. We find evidence of an increase in bias in a limited sample of students that we can follow longitudinally. A significant part of the gap between economics and non-economics students can be explained by differential exposure to female professors.

Work through here is the top link is failing you.  I would note by the way that gender relations in Chile have a reputation for being especially…bifurcated.