Month: November 2018
Teacher expectations matter
From Nicholas W. Papageorge, Seth Gershenson, and Kyung Min Kang:
We develop and estimate a joint model of the education and teacher-expectation production functions that identifies both the distribution of biases in teacher expectations and the impact of those biases on student outcomes via self-fulfilling prophecies. Our approach leverages a unique feature of a nationally representative dataset: two teachers provided their educational expectations for each student. Identification of causal effects exploits teacher disagreements about the same student, an idea we formalize using lessons from the measurement error literature. We provide novel, arguably causal evidence that teacher expectations affect students’ educational attainment: Estimates suggest an elasticity of college completion with respect to teachers’ expectations of about 0.12. On average, teachers are overly optimistic about students’ ability to complete a four-year college degree. However, the degree of over-optimism of white teachers is significantly larger for white students than for black students. This highlights a nuance that is frequently overlooked in discussions of biased beliefs: less biased (i.e., more accurate) beliefs can be counterproductive if there are positive returns to optimism or if there are socio-demographic gaps in the degree of teachers’ optimism; we find evidence of both.
This is the most important thing I will have to tell you today. Here is commentary from Vera.
The new movement of geno-economics
By Jacob Ward at The New York Times. Do read the whole thing, here is just one small bit:
The geno-economists seem confident that human genes have a measurable influence on human outcomes. But publicizing whatever predictive power does lie in our genes runs the risk of misleading the rest of us into believing that control of our genes is control of our future. They’re adamant that their motives are in forestalling the dystopian implications of the work, in fighting off misinformation and misguided policies. “The world in which we can predict all sorts of things about the future based on saliva samples — personality traits, cognitive abilities, life outcomes — is happening in the next five years,” Benjamin says. “Now is the time to prepare for that.”
Via Garett Jones.
Friday assorted links
Everyone is upset at Amazon, but…
When we reported last month on the approximately $4.5 billion that city taxpayers are spending on the “dynamic neighborhood” of Hudson Yards on Manhattan’s West Side, eagle-eyed readers may have noticed that our breakdown of the costs featured a tilde (~) before the $750 million figure for tax breaks for commercial developers — indicating that “this figure is our best guess.”
Now, a draft paper by two New School researchers has conducted an even more comprehensive trawl for Hudson Yards public costs, and while it generally confirms our analysis, it finds a couple of items we missed: A total of $1.1 billion worth of items, in fact, bringing the public price tag to a staggering $5.6 billion, with hundreds of millions of dollars still to flow from city coffers.
Ho hum! It’s not a tech company, so who cares? Here is the article, via Alex X. As for FoxConn and Wisconsin: “Remember: Wisconsin is giving Foxconn more $$$ and incentives than New York, Virginia and Tennessee combined gave Amazon. And the real kicker? Foxconn will create far fewer jobs (13,000) than Amazon (55,000)”
Science is getting less bang for its buck
By Patrick Collison and Michael Nielsen in The Atlantic:
…we ran a survey asking scientists to compare Nobel prizewinning discoveries in their fields. We then used those rankings to determine how scientists think the quality of Nobel prizewinning discoveries has changed over the decades…
Our graph stops at the end of the 1980s. The reason is that, in recent years, the Nobel Committee has preferred to award prizes for work done in the 1980s and 1970s. In fact, just three discoveries made since 1990 have yet been awarded Nobel Prizes. This is too few to get a good quality estimate for the 1990s, and so we didn’t survey those prizes.
However, the paucity of prizes since 1990 is itself suggestive. The 1990s and 2000s have the dubious distinction of being the decades over which the Nobel Committee has most strongly preferred to skip back and award prizes for earlier work. Given that the 1980s and 1970s themselves don’t look so good, that’s bad news for physics…
Why has science gotten so much more expensive, without producing commensurate gains in our understanding?
There is much more evidence and argument at the link. This appendix provides more detail on their empirical work. Self-recommending, if there ever was such a thing.
Do we need a Journal of Controversial Ideas?
That is the topic of my latest column for Bloomberg, here is one excerpt:
Now enter a newly announced project, called the Journal of Controversial Ideas. It will publish one issue per year, devoted to ideas that otherwise may not receive a fair hearing, and it will allow for anonymous or pseudonymous publication. Princeton philosopher Peter Singer is one of the names associated with the journal, which does not yet have an agreement with a publisher.
I am skeptical though not hostile toward this enterprise. It is sad that such a journal is seen as necessary. But I would suggest instead putting forth your ideas on a blog, on Twitter or on YouTube. Many politically incorrect figures have done just that. A Jordan Peterson YouTube lecture might range from the Bible to Jung to a critique of contemporary feminism, none of it refereed, but he has attracted millions of viewers. At the end of it all you get the Jordan Peterson worldview, which I suspect has more resonance than any particular empirical claim Peterson might make along the way.
In an internet-centered intellectual world, what persuades people is reading or hearing a charismatic personality, year in year out, promoting a particular view of the world. A lot of controversial ideas will have to ride that roller coaster, for better or worse.
The Journal of Controversial Ideas is intended to be open access, though without a publishing contract we can’t know if it will have an open online comments section. It would be odd if not (would we have to create a companion Journal of Controversial Comments?), but with open comments you have to wonder whether a prestige publisher will take on the associated libel and reputational risks, and how high status the journal actually will be. It would not be practical to referee the comments, but that may mean the truly open internet, with its free-for-all atmosphere, will remain the dominant source for controversial ideas. “Controversial for me but not for thee” hardly seems like a winning slogan for such a revisionist enterprise.
Overall, I think controversial ideas will do best on the non-refereed internet, but I am not opposed to giving this venture a try. Refereeing is supposed to boost status, but will anyone put a publication here on their tenure vita? And:
To make a controversial idea stick through the academic process, maybe you do have conquer the biases and beat the odds against you, as Harvey Mansfield, Robert P. George and Oded Galor have done (to name just three). You also might pursue a “Straussian” approach, embedding subversive messages in your paper and covering them up with flowery rhetoric, hoping that some but not too many people notice what you are really saying.
Do read the whole thing.
Thursday assorted links
Coasean Skies
Air taxis and delivery drones may soon make the airspace between 200 and 5000 feet above ground level much more valuable. How is this airspace to be regulated? In a very good new paper Brent Skorup draws on Coase, Demsetz, and Ostrom and the law, economics and history of regulated commons to suggest new approaches.
[T]he technological shock—the commercialization of air taxis—will create novel urban airspace scarcity and collective action conflicts. When intended uses conflict, how should airspace be allocated? This is an old problem: the transformation of a common-pool resource in the face of intensive new uses for that resource.
…For traditional aviation, air traffic management is centralized and relies on complex collaboration between airlines, the general aviation industry, air traffic controllers, and regulators. Aircraft routes, payload, slot fees, airport locations, billing, and safe separation between aircraft are all highly regulated components of this interconnected system. Massive economic distortions result from the regulated rationing of airspace and terminal access. Low-altitude airspace (i.e.,200 feet to 5000 feet above ground level) offers a relatively blank slate to explore new models for air transport and to avoid command-and-control mistakes made in the past in aviation.
…Section IV introduces a different idea: that the FAA instead delimit geographic tracts of low-altitude airspace and assign exclusive use licenses to those tracts via auction for a term of years. Flight path, speed, terminal locations, aircraft size, UTM technologies, and pricing choices would largely be delegated to the tract licensees. Finally, Section V explains why this approach, which draws on real-world examples from spectrum auctions and other federal asset markets, may offer more competitive UTMs and dynamic efficiencies for low-altitude air transit. This auction approach also allows aviation regulators to focus less on scientific management of airspace and UTM interoperability and more on aircraft safety, dangerous weather, and inspections.
How much did the housing shock drive political polarization?
From Henry van Straehlen, a job market candidate from Northwestern:
This paper studies the effect of economic conditions on political polarization using micro-data on house prices, mortgages, and individual political contributions. I argue that shocks to housing wealth — the largest asset for most households in the U.S. — lead to political polarization. Using the housing market bust of 2007-2011 as an empirical laboratory, I show that negative shocks to housing wealth increase political polarization. The richness of the data enables me to use individual heterogeneity in housing location and timing of home purchase to disentangle changes in personal wealth from other factors that might be at play in determining political polarization. The effect of housing shocks on polarization is stronger during the crisis, and cannot be attributed to reverse causality or changing neighborhood composition. Survey evidence comparing homeowners and renters shows that only homeowners polarize in response to house price shocks, while renters do not — suggesting that house price shocks are not merely a proxy for other economic shocks. Furthermore, extreme politicians benefit electorally from negative house price shocks to their contributor network, whereas moderate politicians are hurt by negative house price shocks. Financial crises destabilize politics, which then can feed back into the crisis. These results provide insight into the difficulty of adopting structural economic reforms following financial crises.
Work in progress by Henry argues: “I show that when the common ownership between two firms increases through mutual fund acquisition of their stock, the firms converge in political donation behavior and lobbying activity.”
Why aren’t millennials buying boats? (the boat recession)
“So, where are all the boaters your age?” asked a 60-something-year-old, at a patio bar on Gabriola Island in British Columbia. “When I was your age, we all had boats and had great big raft-ups out on the water.”
Our group of under-40 sailors was on a weekend cruise and digging into steaming plates of fish and chips. “I’m not sure,” I answered. “Are there fewer? Maybe it’s because they can’t afford it?”
“Nah,” he said. “It’s those iPads. My grown kids have no sense of adventure, happy to sit around ‘twitting’ all day.”
My husband, Robin, and I had often discussed this question. Having become first-time boat owners only five years before, at ages 24 and 29, we were often the only identifiable 20-somethings at our silver-haired yacht club.
…According to Ellis, boat ownership has seen a steep decline in the 20- to 39-year-old age category, with approximately 41 percent fewer 20- to 39-year-olds owning boats in 2015 than in 2005. In 2005, 4 percent of American males ages 20 to 39 owned a boat; but by 2015, that number dropped to only 2 percent.
Here is the full story, via Craig Richardson.
Twentieth-century cousin marriage rates explain more than 50 percent of variation in democracy across countries today.
That is the last sentence of the abstract in this job market paper, from Jonathan F. Schulz:
Political institutions vary widely around the world, yet the origin of this variation is not well understood. This study tests the hypothesis that the Catholic Church’s medieval marriage policies dissolved extended kin networks and thereby fostered inclusive institutions. In a difference-in-difference setting, I demonstrate that exposure to the Church predicts the formation of inclusive, self-governed commune cities before the year 1500CE. Moreover, within medieval Christian Europe,stricter regional and temporal cousin marriage prohibitions are likewise positively associated with communes. Strengthening this finding, I show that longer Church exposure predicts lower cousin marriage rates; in turn, lower cousin marriage rates predict higher civicness and more inclusive institutions today. These associations hold at the regional, ethnicity and country level. Twentieth-century cousin marriage rates explain more than 50 percent of variation in democracy across countries today.
Here is Jonathan’s (co-authored) working paper on “The origins of WEIRD psychology.“
Ho hum, or hidden externalities?
The ratings agency Fitch shrugged on Tuesday at what it considered the “muted impact” on the economies and credit ratings of New York and Washington.
According to Fitch, 25,000 jobs are the equivalent of about a quarter of a percentage point of all the jobs in metro New York. In metro Washington, they’d represent about three-quarters of a percentage point of the labor force. The Washington region is already growing by about 50,000 jobs, or an Amazon HQ2, each year, according to the D.C. Policy Center. New York over the past year gained about 70,000 jobs.
Here is more from Emily Badger at the NYT.
Wednesday assorted links
1. “…the 2000s should be seen as an exceptional period in the global economy during which multinational firms benefitted from reduced labour costs through offshoring, while capitalising on existing firm-specific intangibles, such as brand names, at little marginal cost.” Link here.
2. What can we learn from Eric Schmidt about defense acquisition?
3. How podcasts work (New Yorker).
4. “Masculinity is an abstract rage to protect.”
5. Douglas Vigliotti interviews me for his podcast.
6. “Jeff Bezos himself might weigh in on dining options.”
7. More of the Antikythera mechanism? Here is my earlier post on the mechanism.
Propaganda, Nation Building and Identity in Rwanda
The lead title is “Erasing Ethnicity,” the authors are Arthur Blouin and Sharun W. Mukand, and the paper is forthcoming in the Journal of Political Economy:
This paper examines whether propaganda broadcast over radio helped to change inter-ethnic attitudes in post-genocide Rwanda. We exploit variation in exposure to the government’s radio propaganda due to the mountainous topography of Rwanda. Results of lab-in-the-field experiments show that individuals exposed to government propaganda have lower salience of ethnicity, increased inter-ethnic trust and show more willingness to interact face-to-face with members of another ethnic group. Our results suggest that the observed improvement in inter-ethnic behavior is not cosmetic, and reflects a deeper change in inter-ethnic attitudes. The findings provide some of the first quantitative evidence that the salience of ethnic identity can be manipulated by governments.
Propaganda works.
The sex recession
From Kate Julian at The Atlantic:
Gen Xers and Baby Boomers may also be having less sex today than previous generations did at the same age. From the late 1990s to 2014, Twenge found, drawing on data from the General Social Survey, the average adult went from having sex 62 times a year to 54 times. A given person might not notice this decrease, but nationally, it adds up to a lot of missing sex. Twenge recently took a look at the latest General Social Survey data, from 2016, and told me that in the two years following her study, sexual frequency fell even further.
Some social scientists take issue with aspects of Twenge’s analysis; others say that her data source, although highly regarded, is not ideally suited to sex research. And yet none of the many experts I interviewed for this piece seriously challenged the idea that the average young adult circa 2018 is having less sex than his or her counterparts of decades past. Nor did anyone doubt that this reality is out of step with public perception—most of us still think that other people are having a lot more sex than they actually are.
I enjoyed this sentence:
In a famous 2007 study, people supplied researchers with 237 distinct reasons for having sex, ranging from mystical (“I wanted to feel closer to God”) to lame (“I wanted to change the topic of conversation”). The number of reasons not to have sex must be at least as high.
This is interesting too:
“Millennials don’t like to get naked—if you go to the gym now, everyone under 30 will put their underwear on under the towel, which is a massive cultural shift,” Jonah Disend, the founder of the branding consultancy Redscout, told Bloomberg last year. He said that designs for master-bedroom suites were evolving for much the same reason: “They want their own changing rooms and bathrooms, even in a couple.” The article concluded that however “digitally nonchalant” Millennials might seem—an allusion, maybe, to sexting—“they’re prudish in person.”
The sex recession remains a puzzle. Here is my much earlier blog post on why people don’t have more sex.