Category: Data Source
The culture that is Italy?
It is not just birds, rabbits and wild boar who meet a sticky end in the Italian hunting season.
According to statistics published today, 35 people have also been killed in the past four months, and another 74 injured. Italy's anti-hunting league, the LAC, said all but one were hunters killed accidentally by their shooting companions.
But the 35th victim was a mushroom collector shot dead near Arezzo in Tuscany. Of the injured, 13 were also non-hunters, mostly people out for a walk in the woods or cycling down a country lane.
The annual bloodletting is a result of the unusual freedom allowed to shooting parties under Italian law. They can go on to private property and fire anywhere not within 50m of a road or 150m of a house.
Here is more.
World Income Inequality
Here, courtesy of Catherine Rampell of Economix, is a remarkable chart from Branko Milanovic's book The Haves and Have Nots. Along the horizontal axis are within-country income percentiles running from the bottom 5% (1st ventile) to the top 5% (20th ventile). Along the vertical axis are world income percentiles.
The graph shows that the bottom 5% of Brazilians are among the poorest people in the world but the top 5% are among the richest. Thus the vertical range of the curve tells us about within-country inequality.
Comparing between countries we see that the poorest 5% of Americans are among the richest people in the world (richer than nearly 70% of other people in the world). The poorest 5% of Americans, for example, are richer than the richest 5% of Indians.
Median-itis and The Great Stagnation
Here is my NYT column from today, on themes relevant to The Great Stagnation. I won't rehash this entire discussion, but I would like to focus on this one column excerpt:
From 1947 to 1973 – a period of just 26 years – inflation-adjusted median income in the United States more than doubled. But in the 31 years from 1973 to 2004, it rose only 22 percent. And, over the last decade, it actually declined.
I am noticing that some reviews or commentaries (and here) are citing per capita income growth as a response to my argument. It is true that per capita income grows at a slower rate post-1973, but my argument is about the slowing down of median income growth and that is a much stronger shift. The productivity data also tell a glum story.
CPI bias can change those numbers in absolute terms (see comments from Russ Roberts), but it also changes the pre-1973 median income growth numbers and arguably more so. The gap remains and TGS refers to the living standard for the average person or household in the United States, not the total amount of innovation, which remains quite high. They're just not innovations with the same trickle-down or broad-based effects as in an earlier era.
Kindle eBooks are themselves a good example. It's a real improvement for a lot of us — especially travelers – but even the median reader, much less the median American, doesn't have a Kindle or buy eBooks. As I argued in The Age of the Infovore, the big gains of late have gone to the extreme information-processors.
I've seen in the MR comments (and elsewhere) a lot of anecdotal comparison of recent gains vs. earlier gains in technology. Don't we now have this, don't we now have that, and so on. Of course. Median incomes have risen somewhat. But, when it comes to the average household, the published numbers for median income are adding up and trying to measure those gains and it turns out their recent rate of growth really has declined. Most serious researchers who work in this area use and accept these numbers as the best available (though they do not in general advocate my causal interpretation; see for instance Mark Thoma or Jacob Hacker).
If the numbers for median income growth are low we ought to take that seriously, as does Scott Sumner. We are not cheerleaders per se (BC: "I'm baffled why Tyler would focus on slight declines in American growth when the world just had the best decade ever." Is it then wrong to focus on any other problems at all? I also was one of the first people to make the "best decade ever" argument, which I still accept.) Medians also matter for the political climate, even though the median earner is not exactly the median voter. Adam Smith's welfare economics was basically that of the median, a point which David Levy has made repeatedly.
I'm also being called a "pessimist" a lot. Yet in my view our current technological plateau won't last forever. That's probably more optimistic than the Hacker-Pierson approach, which requires a Progressive revolution in economic policy (unlikely), although it is not more optimistic than denying the relevance of the numbers.
I'll soon blog some remarks on changing household size as another attempt to avoid confronting the facts about slow median income growth.
Are criminals just stupid?
Kevin Beaver and John Paul Wright report:
An impressive body of research has revealed that individual-level IQ scores are negatively associated with criminal and delinquent involvement. Recently, this line of research has been extended to show that state-level IQ scores are associated with state-level crime rates. The current study uses this literature as a springboard to examine the potential association between county-level IQ and county-level crime rates. Analysis of data drawn from the National Longitudinal Study of Adolescent Health revealed statistically significant and negative associations between county-level IQ and the property crime rate, the burglary rate, the larceny rate, the motor vehicle theft rate, the violent crime rate, the robbery rate, and the aggravated assault rate. Additional analyses revealed that these associations were not confounded by a measure of concentrated disadvantage that captures the effects of race, poverty, and other social disadvantages of the county. We discuss the implications of the results and note the limitations of the study.
Hat tip goes to Kevin Lewis. Elsewhere, again via Kevin, people believe they have more free will than do others.
China fact (book) of the day
When it comes to the overall death toll, for instance, researchers so far have had to extrapolate from official population statistics…Their estimates range from 15 to 32 million excess deaths. But the public security reports compiled at the time, as well as the voluminous secret reports collated by party committees in the last months of the Great Leap Forward, show how inadequate these calculations are, pointing instead at a catastrophe of a much greater magnitude: this book shows that at least 45 million people died unnecessarily between 1958 and 1962.
That is from Frank Dikötter's Mao's Great Famine: The History of China's Most Devastating Catastrophe, 1958-1962, which is one of the scariest books I have read. Here is another passage, I am not sure how well it is sourced:
Mao was delighted. As reports came in from all over the country about new records in cotton, rice, wheat or peanut production, he started wondering what to do with all the surplus food. On August 4 1958 in Xushui, flanked by Zhang Guozhong, surrounded by journalists, plodding through the fields in straw hat and cotton shoes, he beamed: "How are you going to eat so much grain? What are you going to do with the surplus?"
"We can exchange it for machinery," Zhang responded after a pause for thought.
[Showing a poor understanding of Say's Law] "But you are not the only one to have a surplus, others too have too much grain! Nobody will want your grain!" Mao shot back with a benevolent smile.
"We can make spirits of out of taro," suggested another cadre.
"But every county will make spirits! How many tonnes of spirits do we need? Mao mused. "With so much grain, in future you should plant less, work half time and spend the rest of your time on culture and leisurely pursuits, open schools and a university, don't you think?…You should eat more. Even five meals a day is fine!"
Here are some reviews of the book.
Has school segregation gone down since MLK?
I received this very useful email from Ken Hirsch:
I looked into the basis for the statement I read on Marginal Revolution that "American schools are more segregated by race and class today than they were on the day Martin Luther King, Jr. was killed". The source that was given did not actually have statistics going back to the 1960s, but the author of the report, Gary Orfield, pointed me to an earlier report, "Brown at 50: King's Dream or Plessy's Nightmare" (http://tinyurl.com/BrownAt50), which did contain a time series for one measurement, "Percent of Black Students at Majority White Schools". There's a graph of this statistic for Southern black children on the cover of the report which I am attaching to this email.
This statistic is quite problematic. Most starkly, in "majority minority" states, such as Texas and California, this statistic measures the *opposite* of integration. The more evenly distributed that ethnic groups are in schools, the lower the the number. If all schools in California had exactly the same ethnic make-up, there would be no majority white schools, so 0% of black students would be in them! Indeed, in Table 11 from this report (p. 27), California is given as the most segregated state by this measure.
The other two measures that Dr. Orfield uses have similar problems. Most of the change in all three are probably caused by the increase in the percent of Hispanics and the decrease in the percent of non-Hispanic whites, not by segregation. By most mathematically sensible measures, segregation has decreased and integration has increased over the last 20 years. See "Measuring School Segregation" by David M. Frankel and Oscar Volij for details: http://www.econ.iastate.edu/research/working-papers/p11808
The original post was here.
Stata Resources
Here are some Stata resources that I have found useful. Statistics with Stata by Hamilton is good for beginners although it is overpriced. For the basics I like German Rodriguez’s free Stata tutorial best, good material can also be found at UCLA’s Stata starter kit and UNC’s Stata Tutorial; two page Stata is good for getting started quickly.
Christopher Baum’s book An Introduction to Modern Econometrics using Stata is excellent and worth the price. The world is indebted to Baum for a number of Stata programs such as NBERCycles which shades in NBER recession dates on time series graphs–this was a big help in producing graphs for our textbook!–so buy Baum’s book and support a public good.
I have found it hugely useful to peruse the proceedings of Stata meetings where you can find professional guides to using Stata to do advanced econometrics. For example, here is Austin Nichols on Regression Discontinuity and related methods, Robert Guitierrez on Recent Developments in Multilevel Modeling, Colin Cameron on Panel Data Methods and David Drukker on Dynamic Panel Models.
I found A Visual Guide to Stata Graphics very useful and then I lent it to someone who never returned it. I suppose they found it very useful as well. I haven’t bought another copy, since it is fairly easy to edit graphs in the newer versions of Stata. You can probably get by with this online guide.
German Rodriguez, mentioned earlier, has an attractively presented class on generalized linear models with lots of material. The LSE has a PhD class on Stata, here are the class notes: Introduction to Stata and Advanced Stata Topics.
Creating a map in Stata is painful since there are a host of incompatible file formats that have to be converted (I spent several hours yesterday working to convert a dBase IV to dBase III file just so I could convert the latter to dta). Still, when it works, it works well. Friedrich Huebler has some of the details.
The reshape command is often critical but difficult, here is a good guide.
Here are many more sources of links: Stata resources, Stata Links, Resources for Learning Stata, and Gabriel Rossman’s blog Code and Culture.
China Fear of the Day
This NYTimes piece on China and solar power is a must read as it touches upon environmentalism, protectionism, nationalism, the stimulus, the financial crisis and more! Here are a few grafs and comments.
Aided by at least $43 million in assistance from the government of Massachusetts and an innovative solar energy technology, Evergreen Solar emerged in the last three years as the third-largest maker of solar panels in the United States.
But now the company is closing its main American factory, laying off the 800 workers by the end of March and shifting production to a joint venture with a Chinese company in central China. Evergreen cited the much higher government support available in China…[and] plunging prices for solar panels. World prices have fallen as much as two-thirds in the last three years…
Good news, right? Plunging prices for solar is just what we want and shouldn't we applaud subsidies for green energy? Not so fast according to the article:
…solar power experts see broader implications. They say that after many years of relying on unstable governments in the Middle East for oil, the United States now looks likely to rely on China to tap energy from the sun…
China monopolizes the sun!
Ian A. Bowles, the former energy and environment chief for Gov. Deval L. Patrick…said the federal government had not helped the American industry enough or done enough to challenge Chinese government subsidies… “The federal government has brought a knife to a gun fight,” Mr. Bowles said.
I guess Bowles didn't get the memo about the new civility, or perhaps that only applies domestically. The reporters also seem to signal their views.
Evergreen’s joint-venture factory in Wuhan occupies a long, warehouselike concrete building in an industrial park located in an inauspicious neighborhood. A local employee said the municipal police had used the site for mass executions into the 1980s.
Woah, a little gratuitous no?
See here for more of interest including a discussion of how the financial crisis and the Lehman bankruptcy are involved.
Hat tip: Daniel Akst.
U.S. fact of the day
American schools are more segregated by race and class today than they were on the day Martin Luther King, Jr. was killed, 43 years ago. The average white child in America attends a school that is 77 percent white, and where just 32 percent of the student body lives in poverty. The average black child attends a school that is 59 percent poor but only 29 percent white. The typical Latino kid is similarly segregated; his school is 57 percent poor and 27 percent white.
Overall, a third of all black and Latino children sit every day in classrooms that are 90 to 100 percent black and Latino.
That's via Ezra Klein, Dana Goldstein post here, source here. In the meantime, and quite on point, here is one of Chris Christie's biggest mistakes.
Addendum: Here is from Matt Yglesias, another contender for U.S. fact of the day:
If the country as a whole had the same average population density as New Hampshire (!) it would contain about 522 million people…
The paradox of Tunisian water policy
One quality of life measure put Tunisia first in the Arab world. If you look at water policy, the Tunisian government has long had a strong reputation. Here is Wikipedia:
Tunisia has achieved the highest access rates to water supply and sanitation services among the MENA countries through sound infrastructure policy. 96% of urban dwellers and 52% of the rural population already have access to improved sanitation. By the end of 2006, the access to safe drinking water became close to universal (approaching 100% in urban areas and 90% in rural areas). Tunisia provides good quality drinking water throughout the year.
I've never been to Tunisia, but from readings I've found the country especially difficult to understand. They've had a corrupt autocracy for a long time, but some areas of policy they get (inexplicably?) right. And usually they are by far the least corrupt country in the Maghreb. Dani Rodrik called the place an unsung development miracle. Maybe that was exaggerating but for their neighborhood they still beat a lot of the averages and they've had a lot of upward gradients. They've also made good progress on education.
And now this. Perhaps it is no accident this is "the first time that protests have overthrown an Arab leader." The lesson perhaps is that the path toward a much better world involves…small steps. Civil society there is relatively strong and has been so for a while. Democracy is probably not around the corner, but if you're studying social change it's worth spending a lot of time on why Tunisia and Jordan are often so much better run than the other Arab states.
Per capita gdp in Belarus
I am correcting the mistake in the previous post, here is a range of estimates from $5k up through $12k. The point remains that a country, especially a European country with free and wealthy nearby neighbors, should not be content with the lot of Belarus. My apologies for the slip-up.
Addendum: As Blackadder notes, in terms of the Satisfaction with Life Index, they are near the very bottom.
Sex and Statistics or Heteroscedasticity is Hot
Ok Trends has another great post combining statistics, sex and even a little "game theory" (read that in whichever sense you prefer). The statisticians at OK Trends discovered that the number of messages a women receives varies widely even after conditioning on the women's attractiveness rating. Why do some 7's receive far more messages than other 7's? It turns out that it's much better to receive some 10's and some 1's than all 7's. Or as OK Trends beautifully expresses it:
A lot of this can be explained by a non-linear function of messages to attractiveness; that is if 2 men rate three women, A,B,C, as A:{0,10}, B:{5,5} and C:{10, 0} it's not that surprising that A and C each receive one message and B receives none.
But OK Trends argue that more is going on. In a regression of messages on number of rankings in each category (1 being lowest, 5 being highest) they find, not surprisingly, that more high rankings increase messages but also that more low rankings increase messages. That is they find that a ranking of {0,10} can be better than a ranking of {6,10}. Ok Trends hypothesize the following explanation:
Suppose you're a man who's really into someone. If you suspect other men are uninterested, it means less competition. You therefore have an added incentive to send a message.
I have my doubts. Rather I think there are certain types of beauty that greatly attract some men but repel others. Analagously, some people will pay hundreds of dollars for an ounce of caviar that other people won't eat for free. The reason some people love caviar, however, is not that other people dislike it. Instead, it just so happens, that the thing that some people love is the very thing that repels others. We see the same phenomena in art, some people love John Cage, other people would rather listen to nothing at all. 😉
Now if we mix in this kind of beauty–beauty over which there are violent disagreements–with the kind that most people do agree upon (think Haagan-Dazs vanilla ice cream) then I suspect that it will appear that lower rankings increase messages. But what is really going on is that high rankings–conditional on their also being many low rankings–actually signal an extra strong attraction. Someone who tells you that John Cage is their favorite composer is telling you more than someone who says Aaron Copland is their favorite composer.
Note that even if rankings were not public this theory would predict that the same women would receive more messages than their (non-public) rankings would suggest.
Which ever explanation holds, some advice follows: In the marriage market what you want is not so much to increase your attractiveness to the average person but rather to the one person who will cherish your unique features. Thus–conditional on attracting a decent number of suitors from a reasonable pool etc.–what you want to do is accentuate your unique features even if doing so reduces your average ranking. In short, heteroscedasticity makes you hot.
FYI, OK Trends will analyze women's reactions to men in a future post.
New paper on gene-environment interaction
The authors include Eric Turkheimer and the abstract is here (link to paper requires a university connection I believe):
Recent research in behavioral genetics has found evidence for a Gene × Environment interaction on cognitive ability: Individual differences in cognitive ability among children raised in socioeconomically advantaged homes are primarily due to genes, whereas environmental factors are more influential for children from disadvantaged homes. We investigated the developmental origins of this interaction in a sample of 750 pairs of twins measured on the Bayley Short Form test of infant mental ability, once at age 10 months and again at age 2 years. A Gene × Environment interaction was evident on the longitudinal change in mental ability over the study period. At age 10 months, genes accounted for negligible variation in mental ability across all levels of socioeconomic status (SES). However, genetic influences emerged over the course of development, with larger genetic influences emerging for infants raised in higher-SES homes. At age 2 years, genes accounted for nearly 50% of the variation in mental ability of children raised in high-SES homes, but genes continued to account for negligible variation in mental ability of children raised in low-SES homes.
I found this to be an important paper. One lesson is further confirmation that environment matters more for people in less fortunate circumstances (oddly, Progressive "dream policies" would bring about a world where genes matter much more at the margin than they do today). A second lesson is how early "early intervention" has to be for potency, two years and under and that is assuming the procedures work in the first place. The authors criticize Heckman but they do not follow up with much explanation.
For the pointer to the paper I thank Michelle Dawson. Via Bryan Caplan, here are other papers by Turkheimer.
*Progress for the Poor*
That is the new, "Kindle singles-length" book by Lane Kenworthy, who writes the blog Consider the Evidence. It is about how the poor are making, or not making, progress, and also how the poor could make better progress. I especially liked the chapter on how the quality of government expenditure can help alleviate the consequences of poverty. It is due out in 2011, from Oxford University Press, so why are there still no links for the book, Amazon or otherwise? In any case, recommended.
Here is a related paper. Here is Kenworthy on Bill Simmons.
Which shipping company is kindest to your packages?
A field experiment was done, using advanced technology:
So which company treats your packages with the most tender loving care? After crunching the data and averaging the number of spikes recorded by each carrier on each trip, we found that the USPS has the gentlest touch, with a per-trip average of 0.5 acceleration spikes over 6 g's. FedEx and UPS logged an average of three and two big drops per trip, respectively (see graph, next page).
Given those results, we were a little surprised to find that the USPS flipped over its Express Mail packages an awful lot, averaging 12.5 position changes per trip. Meanwhile, FedEx averaged seven position changes, and UPS had an average of four.
All three carriers did a good job at maintaining a stable temperature, but FedEx nabbed the top rating, with an average change of only 26.01 degrees, compared with 26.8 degrees for UPS and almost 32 degrees for the USPS. But the maximum temperatures our package experienced were within 2 degrees, and at no time did a temperature register above 80 degrees or below 47 degrees.
One disheartening result was that our package received more abuse when marked "Fragile" or "This Side Up." The carriers flipped the package more, and it registered above-average acceleration spikes during trips for which we requested careful treatment.
Here is much more, including a nice picture. At the very least, the packages seem to arrive on time.
For the pointer I thank www.bookforum.com.