Results for “Tests”
674 found

Are peaceful or violent protests more effective?

Are peaceful or violent protests more effective at achieving policy change? I study the effect of protests during the Civil Rights Era on legislator votes in the US House. Using a fixed-effects specification, my identifying variation is changes within the congressional district over time. I find that peaceful protests made legislators vote more liberally, consistent with the goals of the Civil Rights Movement. By contrast, violent protests backfired and made legislators vote more conservatively. The effect of peaceful protests was limited to civil rights-related votes. The effect of violent protests extended to welfare-related votes. I explore alternative explanations for these results and show that the results are robust to them. Congressional districts where incumbents were replaced responded more strongly. Furthermore, congressional districts with a larger population share of whites responded more strongly. This is consistent with a signaling model of protests where protests transmitted new information to white voters but not to black voters.

That is the abstract of the job market paper of Gábor Nyéki from Duke.

Were U.S. nuclear tests more harmful than we had thought?

So says Keith A. Meyers, job candidate from University of Arizona.  I found this to be a startling result, taken from his secondary paper:

During the Cold War the United States detonated hundreds of atomic weapons at the Nevada Test Site. Many of these nuclear tests were conducted above ground and released tremendous amounts of radioactive pollution into the environment. This paper combines a novel dataset measuring annual county level fallout patterns for the continental U.S. with vital statistics records. I find that fallout from nuclear testing led to persistent and substantial increases in overall mortality for large portions of the country. The cumulative number of excess deaths attributable to these tests is comparable to the bombings of Hiroshima and Nagasaki.

Basically he combines mortality estimates with measures of Iodine-131 concentrations in locally produced milk, “to provide a more precise estimate of human exposure to fallout than previous studies.” The most significant effects are in the Great Plains and Central Northwest of America, and “Back-of-the-envelope estimates suggest that fallout from nuclear testing contributed between 340,000 to 460,000 excess deaths from 1951 to 1973.”

His primary job market paper is on damage to agriculture from nuclear testing.

Two rationality tests

If you were trying to assess a person’s rationality on the basis of one not-directly-verbal indicator, given his or her behavior over the course of a meal, what would it be?

And if you could ask only one question of a person, to assess his or her rationality, which question would it be?

That’s from me!  As for the first benchmark, you cannot refer to verbal answers to questions you might ask.  You could however nominate “the person hesitated for a long time before answering each question,” or something similar along the behavioral dimension.  That is what I mean by “not-directly-verbal.”

Part of me wishes to suggest “are they carrying a book or not?”, but alas too many semi-rational people don’t do that.  I might consider the process by which they select a menu item and order their food, as a kind of proxy for decision-making more generally.  How well they treat the server would be another variable of interest.

As for the second question, I suggest asking the person who he or she thinks are the rational people.  If the answer is considered and uncertain and complex, upgrade the rationality of that person.  If the answer is dogmatic and refers to holding a particular doctrine…

I considered asking the person if he is himself rational, but that simply will induce lying and false modesty.

Can you think of better tests?

Could Women Be Trusted With Their Own Pregnancy Tests?

The first home pregnancy tests were controversial because it was believed that women could not be trusted to do the tests correctly or to use the results appropriately:

NYTimes: When a mail-order New York firm tried to sell Organon test kits to American consumers in 1971, it faced opposition from the United States Public Health Service. In 1973, a New Jersey drugstore bought kits made by the drug company Roche and offered fast and private tests to their customers, and though the technology was similar to that available in medical clinics, the state medical examiner questioned the legality of the service.

Why so much opposition? Some regulators worried that “frightened 13-year-olds” would be the main users of the test kits. But after the product did become available in the United States in 1977, it appealed instead to college-age and married women — many of whom desperately hoped for children.

Even so, the Texas Medical Association warned that women who used a home test might neglect prenatal care. An article in this newspaper in 1978 quoted a doctor who said customers “have a hard time following even relatively simple instructions,” and questioned their ability to accurately administer home tests. The next year, an article in The Indiana Evening Gazette in Pennsylvania made almost the same claim: Women use the products “in a state of emotional anxiety” that prevents them from following “the simplest instructions.”

The tale of the home pregnancy test is not unique. Breakthroughs that give patients control over their bodies are often resisted. Again and again, the same questions come up: Are patients smart enough? Can they handle bad news? And do they have the right to private information about their bodies?

I wrote about these issues in Our DNA, Our Selves which discussed the FDA’s unconstitutional over-regulation of DNA tests. The legal questions in that case are yet to be fully resolved but the technology is pushing towards the freedom to know our own bodies.

Two misunderstood movies, two Rorschach tests (not too many spoilers here)

American Sniper is one of the best anti-war movies I have seen, ever.  But it shows the sniper-assassin, and his killing, to be sexy, and to be regarded as sexy by women, while the rest of war is dull and stupid.  (Even the two enemy snipers are quite attractive and fantastic figures, and there is a deliberate parallel between the family life of the Syrian sniper and the American protagonist.  The klutziness of the non-assassin soldiers limited how many African-Americans and Hispanics they were willing to cast in those roles, as it is easiest to make white guys look crass in this way without causing offense.)  By making the attractions of war palpable, this film disturbs and confuses people and also occasions some of the worst critical reviews I have read.  It also, by understanding and then dissecting the attractions of blood lust, becomes a quite convincing anti-war movie, if you doubt this spend a few months studying The Iliad.  (By the way, Clint Eastwood, the director and producer, describes the movie as anti-war.)  The murder scenes create an almost unbearable tension, the sandstorm is a metaphor for our collective fog, and they had the stones to opt for the emotional overkill of four rather than just three tours of duty.  Iraq is presented as a hopeless wasteland with nothing of value or relevance to the United States, and at the end of the story America proves its own worst enemy.  It is not clear who ever gets over having killed and fought in a war (can anything else be so gripping?…neither family life nor sex…), even when appearances suggest a kind of normality has returned.  The generational cycle is in any case replenished.  I say A or A+, both as a movie and as a Rorschach test.

Two Days, One Night has some of the worst economics I have seen in a movie, ever.  It would be brilliant as a kind of Randian (or for that matter Keynesian) meta-critique of the screwed up nature of Belgian labor markets and social norms, and most of all a critique of the inability of the Belgian intelligentsia to understand this, except it is not.  It is meant as a straight-up plea for sympathy for the victim and as such it fails miserably, even though as a movie it embodies reasonably good production values.  Everything in the workplace of this solar power company is zero-sum across the workers and we never see why.  The protagonist campaigns to get her job back, but never asks or even considers how she might improve her productivity or attitude, asking only on the basis of need.  (And she is turned down only on the basis of need.)  At one point her employer states the zero marginal product hypothesis quite precisely, something like “when you took time off, we saw that sixteen people could do the work of seventeen.”  She never asks if there might be some other way she could contribute — but she does need the money — nor does the notion of a better job match somewhere else rear its head.  The depictions of financial hardship confuse wealth and income, basic survival and discretionary spending.  The rave reviews this movie has received represent yet another Rorschach test and one which virtually every commentator seems to have failed.

The growth of on-line tests in assessment (average is over)

This continues to be a growing trend:

T-Mobile asks job applicants to take this [problem-solving, for a customer] test before inviting them for an interview because the company has found powerful correlations between the online assessments and success on the job. High scorers tend to resolve customer calls about 25 seconds faster than those who receive low scores. That means they can handle one more call a day and about 250 more a year.

More generally:

Companies are using these tests to evaluate skills and personalities for job openings at every rung of the career ladder, from bank teller to C-suite executive. They are not merely on-screen versions of decades-old paper employment tests. They are built on the power of big data: Creators have harnessed a massive trove of results to help companies pinpoint the kind of worker who might thrive in a particular job.

The legion of tests is only growing:

Some tests evaluate a specific skill, such as how quickly and accurately someone can make change from an onscreen cash register or program software in the Java coding language. Many tests incorporate simulations of scenarios one might encounter on the job. Marriott International, for example, shows housekeeping applicants a photo of a landscaped area at one of its hotels and asks candidates to determine what’s wrong with it. (Perhaps a gardening tool was not put away properly). In one of CEB’s tests for a supervisory role, applicants might have to demonstrate how they would talk to an employee who was coming in late and missing important meetings.

We are entering a new “meritocracy,” at least for people who test well, especially on-line:

Providers say the tests hold the promise of leveling the playing field for job applicants by removing the chance of bias that comes with a traditional résumé screening. The tests can’t distinguish, for example, if a candidate didn’t attend a top-tier college, is currently unemployed or is a woman or minority.

“In many cases, algorithms can trump instinct on staffing,” said John Boudreau, a professor in the business school at the University of Southern California, adding that decades of research have found that tests can serve as reliable barometers of certain personality traits, such as conscientiousness.

The full story, by Sarah Halzack, is here.

Markets in everything, positive pregnancy tests

The latest, uh, must-have appears to be positive pregnancy test results.

Women across the country are selling — and buying — them on Craigslist.

One post from Buffalo, New York, sums up the appeal for potential shoppers:

“Wanna get your boyfriend to finally pop the question? Play a trick on Mom, Dad or one of your friends? I really don’t care what you use it for.”

That particular test was going for the reasonable rate of $25 dollars. The tests in Texas seem to be slightly more expensive, at $30 a pop.

There is more here, via Marcela Veselková.

Increased aggression during human group contests when competitive ability is more similar

From Stulp G, Kordsmeyer T, Buunk AP, Verhulst S.:

Theoretical analyses and empirical studies have revealed that conflict escalation is more likely when individuals are more similar in resource-holding potential (RHP). Conflicts can also occur between groups, but it is unknown whether conflicts also escalate more when groups are more similar in RHP. We tested this hypothesis in humans, using data from two professional sports competitions: football (the Bundesliga, the German first division of football) and basketball (the NBA, the North American National Basketball Association). We defined RHP based on the league ranks of the teams involved in the competition (i.e. their competitive ability) and measured conflict escalation by the number of fouls committed. We found that in both sports the number of fouls committed increased when the difference in RHP was smaller. Thus, we provide what is to our best knowledge the first evidence that, as in conflicts between individuals, conflicts escalate more when groups are more similar in RHP.

The paper is here, hat tip goes to Neuroskeptic.  One hypothesis is behavioral.  The other hypothesis is more directly microeconomic.  Perhaps fouling has positive expected returns within the context of the game, but costs a player long-term reputation, risks long-term retaliation, and so on, and thus the aggression is deployed more in the really important situations.

Should we renorm IQ tests?

The year in which IQ is tested can make the difference between life and death for a death row inmate. It also can determine the eligibility of children for special services, adults’ Social Security benefits and recruits’ suitability for certain military careers, according to a new study by Cornell University researchers.

That’s because IQ scores tend to rise 5 to 25 points in a single generation. This so-called “Flynn effect” is corrected by toughening up the test every 15 to 20 years to reset the mean score to 100. A score from a test taken at the end of one cycle can vary widely from a score derived from a test taken at the beginning of the next cycle, when the test is more difficult, says Stephen J. Ceci, professor of human development at Cornell.

In other words, our definitions of intelligence and mental retardation are more relativistic than we would like to think. Yet the law, and various institutional categories, look to IQ scores as if they were fully objective. Here is the full story.

The Flynn effect implies, if you take it literally, that most people were morons as recently as a few generations ago. Just think, “someone who scored among the best 10% a hundred years ago, would nowadays be categorized among the 5% weakest. That means that someone who would be considered bright a century ago, should now be considered a moron!” So much as I believe in the idea of progress, I don’t think we can take the numbers at face value. If you are not convinced, try reading David Hume. Here is another survey of hypotheses, and why they fail to explain the data.

We’re past the point where nutrition can explain the rise in IQ scores, and more generally the Flynn effect numbers are inconsistent with more general data about the limits on environment for improving IQ scores. The less culturally specific the test, the stronger the Flynn effect appears. Bill Dickens and Flynn offer some interesting evidence on how genes and environment interact.

My favorite hypothesis, which has no hard data to support it, cites “the impact of the visual and spatial demands that accompany a television-laden, video-game-rich world. ” In other words, TV helps us do well on IQ tests. This does not explain why the Flynn effect predates 1950, but perhaps the more general increase in world complexity forces our brains to adapt. In earlier times people were “smart enough” for their environments, and still could create brilliant achievements on the frontiers they faced, still they might have been ill-suited to live in modern times.

Why the New Pollution Literature is Credible

My recent post, Air Pollution Reduces Health and Wealth drew some pushback in the comments, some justified, some not, on whether the results of these studies are not subject to p-hacking, forking gardens and the replication crisis. Sure, of course, some of them are. Andrew Gelman, for example, has some justified doubt about the air filters and classroom study. Nevertheless, I don’t think that skepticism about the general thrust of the results is justified. Why not?

First, go back to my post Why Most Published Research Findings are False and note the list of credibility checks. For example, my rule is trust literatures not papers and the new pollution literature is showing consistent and significant negative effects of pollution on health and wealth. Some might respond that the entire literature is biased for reasons of political correctness or some such and sure, maybe. But then what evidence would be convincing? Is skepticism then justified or merely mood affiliation? And when it comes to action should we regard someone’s prior convictions (how were those formed?) as more accurate then a large, well-published scientific literature?

It’s not just that the literature is large, however, it’s that the literature is consistent in a way that many studies in say social psychology were not. In social psychology, for example, there were many tests of entirely different hypotheses–power posing, priming, stereotype threat–and most of these failed to replicate. But in the pollution literature we have many tests of the same hypotheses. We have, for example, studies showing that pollution reduces the quality of chess moves in high-stakes matches, that it reduces worker productivity in Chinese call-centers, and that it reduces test scores in American and in British schools. Note that these studies are from different researchers studying different times and places using different methods but they are all testing the same hypothesis, namely that pollution reduces cognitive ability. Thus, each of these studies is a kind of replication–like showing price controls led to shortages in many different times and places.

Another feature in favor of the air pollution literature is that the hypothesis that pollution can have negative effects on health and cognition wasn’t invented yesterday along with the test (we came up with a new theory and tested it and guess what, it works!). The Romans, for example, noted the negative effect of air pollution on health. There’s a reason why people with lung disease move to the countryside and always have.

I also noted in Why Most Published Research Findings are False that multiple sources and types of evidence are desirable. The pollution literature satisfies this desideratum. Aside from multiple empirical studies, the pollution hypothesis is also consistent with plausible mechanisms and it is consistent with the empirical and experimental literature on pollution and plants and pollution and animals. See also OpenPhilanthropy’s careful summary.

Moreover, there is a clear dose-response effect–so much so that when it comes to “extreme” pollution few people doubt the hypothesis. Does anyone doubt, for example, that an infant born in Delhi, India–one of the most polluted cities in the world–is more likely to die young than if the same infant grew up (all else equal) in Wellington, New Zealand–one of the least polluted cities in the world?  People accept that “extreme” pollution creates debilitating effects but they take extreme to mean ‘more than what I am used to’. That’s not scientific. In the future, people will think that the levels of pollution we experience today are extreme, just as we wonder how people could put up with London Fog.

What is new about the new pollution literature is more credible methods and bigger data and what the literature shows is that the effects of pollution are larger than we thought at lower levels than we thought. But we should expect to find smaller effects with better methods and bigger data.  (Note that this isn’t guaranteed, there could be positive effects of pollution at lower levels, but it isn’t surprising that what we are seeing so far is negative effects at levels previously considered acceptable.)

Thus, while I have no doubt that some of the papers in the new pollution literature are in error, I also think that the large number of high quality papers from different times and places which are broadly consistent with one another and also consistent with what we know about human physiology and particulate matter and also consistent with the literature on the effects of pollution on animals and plants and also consistent with a dose-response relationship suggest that we take this literature and its conclusion that air pollution has significant negative effects on health and wealth very seriously.

Air Pollution Reduces Health and Wealth

Great piece by David Wallace-Wells on air pollution.

Here is just a partial list of the things, short of death rates, we know are affected by air pollution. GDP, with a 10 per cent increase in pollution reducing output by almost a full percentage point, according to an OECD report last year. Cognitive performance, with a study showing that cutting Chinese pollution to the standards required in the US would improve the average student’s ranking in verbal tests by 26 per cent and in maths by 13 per cent. In Los Angeles, after $700 air purifiers were installed in schools, student performance improved almost as much as it would if class sizes were reduced by a third. Heart disease is more common in polluted air, as are many types of cancer, and acute and chronic respiratory diseases like asthma, and strokes. The incidence of Alzheimer’s can triple: in Choked, Beth Gardiner cites a study which found early markers of Alzheimer’s in 40 per cent of autopsies conducted on those in high-pollution areas and in none of those outside them. Rates of other sorts of dementia increase too, as does Parkinson’s. Air pollution has also been linked to mental illness of all kinds – with a recent paper in the British Journal of Psychiatry showing that even small increases in local pollution raise the need for treatment by a third and for hospitalisation by a fifth – and to worse memory, attention and vocabulary, as well as ADHD and autism spectrum disorders. Pollution has been shown to damage the development of neurons in the brain, and proximity to a coal plant can deform a baby’s DNA in the womb. It even accelerates the degeneration of the eyesight.

A high pollution level in the year a baby is born has been shown to result in reduced earnings and labour force participation at the age of thirty. The relationship of pollution to premature births and low birth weight is so strong that the introduction of the automatic toll system E-ZPass in American cities reduced both problems in areas close to toll plazas (by 10.8 per cent and 11.8 per cent respectively), by cutting down on the exhaust expelled when cars have to queue. Extremely premature births, another study found, were 80 per cent more likely when mothers lived in areas of heavy traffic. Women breathing exhaust fumes during pregnancy gave birth to children with higher rates of paediatric leukaemia, kidney cancer, eye tumours and malignancies in the ovaries and testes. Infant death rates increased in line with pollution levels, as did heart malformations. And those breathing dirtier air in childhood exhibited significantly higher rates of self-harm in adulthood, with an increase of just five micrograms of small particulates a day associated, in 1.4 million people in Denmark, with a 42 per cent rise in violence towards oneself. Depression in teenagers quadruples; suicide becomes more common too.

Stock market returns are lower on days with higher air pollution, a study found this year. Surgical outcomes are worse. Crime goes up with increased particulate concentrations, especially violent crime: a 10 per cent reduction in pollution, researchers at Colorado State University found, could reduce the cost of crime in the US by $1.4 billion a year. When there’s more smog in the air, chess players make more mistakes, and bigger ones. Politicians speak more simplistically, and baseball umpires make more bad calls.

As MR readers will know Tyler and I have been saying air pollution is an underrated problem for some time. Here’s my video on the topic:

Nu, a variant of real concern

Here is the Eric Topol thread.  Do read it.  Here is the scary graph, based on preliminary data.  Here is Bloom Lab.  Here is a layperson’s take from the Times of London:

When was the variant first discovered?
South African authorities raised the alarm at 2pm on Tuesday of this week, when they found samples with a significant number of worrying mutations.

The samples dated from tests taken on November 14 and 16. On Wednesday, even as scientists were analysing the genome, other samples were found in Botswana and China, originating from travellers from South Africa.

Why were scientists initially concerned by this variant?
The spike protein is the tool a virus uses to enter cells, and the part of it our vaccines are trained to spot. This variant had 32 mutations in the spike — meaning it would look different to our immune system and behave differently when attacking a body. As a virologist at Imperial College put it, it was a “horrific spike profile”.

Why has worry increased over the course of the week?
When geneticists and virologists looked at the mutations they realised there was a high likelihood they could increase its transmissibility or help it evade immunity. But these concerns were still theoretical. However, today South African scientists spotted a quirk in the testing regimen. PCR tests look for three genes in the coronavirus and amplify them. If, however, the virus was this variant they were only able to amplify two.

In the province of Gauteng, where the proportion of tests coming back positive has rocketed to one in three, they found the proportion in which only two genes were amplified has also rocketed.

What does this mean?
There are three options. It is still possible — though unlikely — this is chance, with the variant’s apparently increased spread relating to an unusual cluster. If it does have a genuine advantage, then it is either better able to spread or better able to infect people who have prior immunity — either from vaccination or infection. Or, it is both.

This might come to nothing, but it is definitely a matter of concern.  One more general point is that even if Nu is a non-event, it seems to show that the space for possible significant mutations is largely than we had thought.

Model this Apple pricing decision

Apple has one new product that’s already so back-ordered it won’t arrive in time for Christmas. It’s a polishing cloth. Priced at $19.

Unveiled in October after Apple showed off its new line of gadgets, the soft, light gray square is made of “nonabrasive material” and embossed with Apple’s logo. During tests, the rag worked like other microfiber cloths that list for less than half that price. So…why $19?

As it happens, Apple’s pricing strategy rarely allows accessories to fall below that threshold. The 6.3-inch swatch of fabric sits beside 17 other Apple-branded items on the company’s website—a mélange of charging cables, dongles and adapters—each priced at $19. Some, such as the wired earbuds and charging adapter, were once included with new iPhones.

Those $19 Apple items—together with the Apple Watch, AirPods and other small gadgets—are part of the company’s growing Wearables, Home and Accessories category, which had more than $8 billion in revenue in the quarter that ended in October.

Almost every Apple price ends in the number “9.”  Would it matter if we all carried around $30 bills?  There is further discussion in this Galvin Brown WSJ piece.

Via the excellent Samir Varma.