Results for “Tests” 772 found
Do minimum parking requirements matter?
W. Bowman Cutter, Sofia F. Franco, and Autumn DeWoody have a new paper titled "Do Minimum Parking Requirements Force Developers to Provide More Parking than Privately Optimal?" The abstract is this:
Minimum parking requirements are the norm for urban and suburban development in the United States (Davidson and Dolnick (2002)). The justification for parking space requirements is that overflow parking will occupy nearby street or off-street parking. Shoup (1999) and Willson (1995) provides cases where there is reason to believe that parking space requirements have forced parcel developers to place more parking than they would in the absence of parking requirements. If the effect of parking minimums is to significantly increase the land area devoted to parking, then the increase in impervious surfaces would likely cause water quality degradation, increased flooding, and decreased groundwater recharge. However, to our knowledge the existing literature does not test the effect of parking minimums on the amount of lot space devoted to parking beyond a few case studies. This paper tests the hypothesis that parking space requirements cause an oversupply of parking by examining the implicit marginal value of land allocated to parking spaces. This is an indirect test of the effects of parking requirements that is similar to Glaeser and Gyourko (2003). A simple theoretical model shows that the marginal value of additional parking to the sale price should be equal to the cost of land plus the cost of parking construction. We estimate the marginal values of parking and lot area with spatial methods using a large data set from the Los Angeles area non-residential property sales and find that for most of the property types the marginal value of parking is significantly below that of the parcel area. This evidence supports the contention that minimum parking requirements significantly increase the amount of parcel area devoted to parking.
The paper is here. Here is a related paper, or here.
What me, worry?
Europe's "stress tests" were intended to gauge the ability of large banks to weather an economic storm. But the exams relied on some surprisingly docile economic assumptions.
In some of the 20 countries that conducted the tests, regulators figured that property values would keep rising or hold steady in a worst-case economic scenario.
In other cases, unemployment rates in a double-dip recession crept up by as little as 0.1 percentage point from the tests' so-called benchmark scenario, which is based on current economic conditions.
In Austria, for instance, the recession scenario involved house prices rising two percent the first year and rising 2.7 percent the year after. Here is further information. What would a rational Bayesian say? What would Will Wilkinson say? – "My kingdom for a futarchy!"
Here is further comment.
Assorted links
1. Henry on Gellner.
2. Unlucky thief steals iPhone being used in GPS tracking tests.
3. Paul Romer on peeing in public.
4. Is Cow Clicker a money pump?
5. What Germans predicted in 1910.
6. "It's the best critique of street dance I've ever seen": the Amish visit London.
Is Creativity Declining?
Nobody would argue that Torrance’s tasks, which have become the gold standard in creativity assessment, measure creativity perfectly. What’s shocking is how incredibly well Torrance’s creativity index predicted those kids’ creative accomplishments as adults. Those who came up with more good ideas on Torrance’s tasks grew up to be entrepreneurs, inventors, college presidents, authors, doctors, diplomats, and software developers. The correlation to lifetime creative accomplishment was more than three times stronger for childhood creativity than childhood IQ.
Like intelligence tests, Torrance’s test–a 90-minute series of discrete tasks, administered by a psychologist–has been taken by millions worldwide in 50 languages. Yet there is one crucial difference between IQ and CQ scores. With intelligence, there is a phenomenon called the Flynn effect–each generation, scores go up about 10 points. Enriched environments are making kids smarter. With creativity, a reverse trend has just been identified and is being reported for the first time here: American creativity scores are falling.
From Newsweek. I am not at all convinced that creativity is on the decline. The study cited seems to be unpublished and there isn't much on the author's website which is a little, well, too creative for my tastes. Nevertheless, the Torrance test and its correlation with lifetime creative is interesting and a good reminder of what IQ tests do not reveal. I also liked this bit:
When faculty of a major Chinese university asked Plucker to identify trends in American education, he described our focus on standardized curriculum, rote memorization, and nationalized testing. “After my answer was translated, they just started laughing out loud,” Plucker says. “They said, ‘You’re racing toward our old model. But we’re racing toward your model, as fast as we can.’ “
Scientific hypotheses from 1956
This article was from the Guardian:
Intelligence tests recently carried out among more than a thousand children in Wolverhampton schools appear to show a striking and quite unexpected increase in the mental capacity of children born since 1945. A psychiatrist concerned in the tests has suggested that the most probable hypothesis to account for this change is the effect on the brain of the increase in "background radio-activity".
For the pointer I thank Michelle Dawson.
Privacy in Germany, it’s for banks too
Until now, Berlin has resisted the US-style publication of information about banks’ capital cushions because it feared the results could be manipulated, could send the wrong signals, and break German laws about commercial secrets.
The government’s U-turn is likely to rouse the anger of German banks, which have been in lock-step with Berlin so far in resisting the publication – and under German law they would have to approve any public use of their own data.
Deutsche Bank chief executive Josef Ackermann last week warned that publishing the results of stress tests would be “very, very dangerous” if there were no “backstop facilities” in place to allow stressed banks to draw on new capital.
The full story, which includes information on Spain, is here. The last paragraph may sound slightly ridiculous to an American reader — why make such an admission of vulnerability? Yet in Germany privacy norms and laws are quite strong and virtually everyone will grant you the right to assert privacy. If you are waiting at an ATM, you had better stand very far back, behind the person at the machine, otherwise you will hear about it. Everyone at the university keeps their office doors closed, although not for the American reason of avoiding students. The goal is to have a closed door and a private space between you and the rest of the world. German blog readers who see you in public will talk less to you than would American blog readers. "Direct mail" is considered not only a nuisance, but also a privacy violation. People work next to each other for twenty years, and it's still just "Frau Mueller," etc.
GMOs come to Europe, sort of
The potato, the first genetically engineered organism to be allowed in the European Union in more than a decade, was planted on 16 acres of land on the fringes of this town in southwestern Sweden, after a quarter century of bureaucratic wrangling.
Although inedible, Amflora is a kind of miracle potato on two counts: for one, there is its starch content, which makes it precious to the starch industry, a major employer in Sweden; and then there is its feisty resilience in surviving some 25 years of tests, regulations, rules, ordinances and applications for approval by both Sweden and the European Union, of which Sweden is a member.
Here is more information. I had not know that GMOs were given partial European clearance in 2004, though they still face very stringent regulatory obstacles.
FDA Overreach
From the Washington Post:
The Food and Drug Administration on Friday ordered five companies that offer genome-sequencing tests to consumers, or that provide the scientific services for them, to prove the validity of such products.
The FDA said the tests, which scan a person's DNA for gene variants associated with specific diseases, are medical devices requiring the agency's approval.
The ability of genetic tests to predict diseases is currently limited; if the FDA were simply to require firms to acknowledge this point, say with a clear statement of probabilities, that would be one thing (although this task is better met by the FTC under advertising regulation). But the FDA is brazenly overreaching in trying to regulate genetic tests as medical devices. First, there is no question that these tests are safe–safer than brushing your teeth!–and also effective in identifying genetic markers. Thus, there is no medical reason whatsoever for regulation.
Moreover, genetic tests provide information, personal information about our bodies and our selves. The FDA has no standing to interfere with the provision of such information.
Consider, I swab the inside of my cheek and send the sample to a firm. The idea that the FDA can rule on what the firm can and cannot tell me about my own genes is absurd–it's no different than the FDA trying to regulate what my doctor can tell me after a physical examination or what my optometrist can tell me after an eye examination (Please read the first line. "G T A C C A…").
The idea that the FDA can regulate and control what individuals may learn about their own bodies is deeply offensive and, in my view, plainly unconstitutional.
Sebastian Mallaby on Paul Romer
The focus of this feature article, from The Atlantic, is charter cities. Here is one good excerpt:
Ever since the setback in Madagascar, Romer has been coy, for obvious reasons, about which governments are interested in his plan. But he remains optimistic. “I revived growth theory. I made technology work in higher ed. I am two for two, and I think the impossible can be done,” he told me cheerfully. He added that the Daewoo deal might not have been the main impetus for the coup in Madagascar; the real reasons for Ravalomanana’s downfall lay in idiosyncratic local rivalries, even if the opposition exploited sensitivities over land to incite antigovernment protests. I suggested that the fact that land concessions could trigger such emotions was still not a good sign. Romer stopped, considered, and chose his words carefully.
“Anything that involves land can be manipulated by people who want to rise up against a leader,” he began. “You have to find a place where there’s a strong enough leader with enough legitimacy to do this knowing that he’s going to get attacked. It narrows the options quite a bit. But we shouldn’t give up without trying a few more places.” In short, a disappointment with one client is no excuse for failing to pitch other ones. Any entrepreneur knows that.
Does Professor Quality Matter?
That's the title of the new lead article (gated) in the Journal of Political Economy, by Scott E. Carrell and James E. West, and here is the answer:
In primary and secondary education, measures of teacher quality are often based on contemporaneous student performance on standard-ized achievement tests. In the postsecondary environment, scores on student evaluations of professors are typically used to measure teaching quality. We possess unique data that allow us to measure relative student performance in mandatory follow-on classes. We compare metrics that capture these three different notions of instructional quality and present evidence that professors who excel at promoting contemporaneous student achievement teach in ways that improve their student evaluations but harm the follow-on achievement of their students in more advanced classes.
I found this to be an impressive piece of research. Here is one summary sentence:
The overall pattern of the results shows that students of less experienced and less qualified professors perform significantly better in the contemporaneous course being taught. In contrast, the students of more experienced and more highly qualified introductory professors perform significantly better in the follow-on courses.
Here is an ungated version, it may or may not be exactly the same.
The 1964 Civil Rights Act in the 21st Century
Rand Paul's remarks about the 1964 Civil Rights Act brought forth lots of talk about libertarians and lunch counters but almost no discussion of how the Civil Rights Act actually works in the twenty-first century. Yesterday provided a nice reminder.
I won't comment on Lewis v. City of Chicago directly because it was decided on technical matters (the Supreme Court ruled that black firefighters in Chicago did not miss a deadline to argue that a test disproportionately hurt their chances of employment). The underlying facts, however, are of interest not because they are especially unusual but because they are common. From Fire Law:
The case, Lewis v. Chicago, involved alleged discrimination against African American applicants for the Chicago Fire Department who took a test in 1995.
The department set a passing score of 64 on the exam. Applicants who scored at least 64 but below 89 were informed that they passed the test, but would probably not be hired given the number of candidates who scored 89 or above. [26,000 applied and there were only a few hundred jobs, AT] Applicants scoring 89 and above were classified as “well qualified”.
The majority of “well-qualified” applicants were white. Only 11 percent were black…
The trial court sided with the black applicants, and ordered the city to hire 132 randomly selected African American applicants who scored above 64. The court also ordered the city to divide backpay owed among the rest of the black applicants.
White, Asian and Hispanic applicants who also scored above 64 but below the 89 standard were not offered employment or backpay.
Perhaps you are wondering about the tests? You would be hard pressed to find any obvious racial bias. I haven't found the Chicago test online but you can find similar tests from New York (also the subject of lawsuits) here. Here is a sample questions from New York.
Nowadays the Chicago fire department simply gives everyone an easy test and then they hire randomly.
The economic effects of disenfranchisement
Via Chris Blattman, here is a newish paper by Suresh Naidu, on how disenfranchisement translated into inferior economic outcomes for African-Americans:
This paper estimates the political and economic effects of the 19th century disenfranchisement of black citizens in the U.S. South. Using adjacent county-pairs that straddle state boundaries, I rst examine the effect of voting restrictions on political competition. I find that poll taxes and literacy tests each lowered overall electoral turnout by 10-23% and increased the Democratic vote share in national elections by 5%-10%. Second, employing newly collected data on schooling inputs, I show that disenfranchisement reduced the teacher-child and teacher-student ratio in black schools. Finally, I develop a model of suffrage restriction and redistribution in a 2-factor economy with occupational choice to generate sufficient statistics for welfare analysis of the incidence of black disenfranchisement. Consistent with the model, disenfranchised counties experienced a 7% increase in land and farm values per decade, despite a 4% fall in the black population share. The estimated factor market responses suggest that black labor bore a collective loss from disenfranchisement equivalent to at least 13% of annual income, much of which was transferred to landowners.
Here is Naidu's home page. Where did he end up getting a job?
Gattaca University
From the NYTimes, Berkeley will give its students genetic tests.
…this year’s incoming freshmen at the University of California, Berkeley, will get something quite different: a cotton swab on which they can, if they choose, send in a DNA sample.
The university said it would analyze the samples, from inside students’ cheeks, for three genes that help regulate the ability to metabolize alcohol, lactose and folates.
Those genes were chosen not because they indicate serious health risks but because students with certain genetic markers may be able to lead healthier lives by drinking less, avoiding dairy products or eating more leafy green vegetables.
Don't be surprised if this is soon canceled.
Fairtest
Tim Harford gives his stamp of approval to randomized trials:
What is missing is the political demand for tests of what really works. Too many policies on education, welfare and criminal justice are just so much homeopathy: cute-sounding stories about what works leaning more on faith than on evidence. Politicians and civil servants, faced with some fancy new idea, should get into the habit of asking for a proper randomised trial. And we, as citizens, should be equally demanding….
We’ve had FairTrade coffee – what about FairTest policies? Most voters don’t know much about randomisation or trial protocols, but they’ll know when they see the FairTest logo that a policy has had a proper, scientific test to see if it works.
Small steps toward a better world
In Hawaii, Kaiser Permanente has started a pilot project that churn through its database of patient data to predict which patients might need which tests – and then sends individuals email alerts suggesting they come in for a test or checkup. It's the same sort of technology that Netflix uses to recommend movies. And the Cleveland Clinic has teamed up with Microsoft to bring self-monitoring tools to patients managing chronic diseases, successfully engaging them in better health behaviors without expensive visits to the hospital.
Here is more, via Steve Silberman. How much of the health care cost-saving revolution will occur in the hands of the individual patient?