This is a continuation of the Steve Sales debunking of abortion lowers the crime rate. Adam sent this link to me as validation to his thoughts on the issue.
JRH 3/19/11
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Part 2: Levitt's response to the Freakonomics abortion-cut-crime theory fiasco
Levitt blogs:
Everything in Freakonomics is wrong!
Or at least that is the impression you might get if you read this article in today’s Wall Street Journal.
Or at least that is the impression you might get if you read this article in today’s Wall Street Journal.
I will post a longer blog entry once I have had time to fully digest the working paper by Foote and Goetz which is the basis for the article.
For now, I will say just a few things:
1) It is not at all clear from the WSJ article is that Foote and Goetz are talking about only one of the five different pieces of evidence we put forth in our paper. They have no criticisms of the other four approaches, all of which point to the same conclusion.
2) There was a coding error that led the final table of my paper with John Donohue on legalized abortion to have specifications that did not match what we said we did in the text. (We’re still trying to figure out where we went wrong on this.) This is personally quite embarrassing because I pride myself on being careful with data. Still, that embarrassment aside, when you run the specifications we meant to run, you still find big, negative effects of abortion on arrests (although smaller in magnitude than what we report). The good news is that the story we put forth in the paper is not materially changed by the coding error.
3) Only when you make other changes to the specification that Foote and Goetz think are appropriate, do the results weaken further and in some cases disappear. The part of the paper that Foote and Goetz focus on is one that is incredibly demanding of the data. For those of you who are technically minded, our results survive if you include state*age interactions, year*age interactions, and state*year interactions. (We can include all these interactions because we have arrest data by state and single year of age.) Given how imperfect the abortion data are, I think most economists would be shocked that our results stand up to removing all of this variation, not that when you go even further in terms of demands on the data things get very weak.
Again, as I said, I will post again on this subject once I have had a chance to carefully study the details of what they have done, and after I have been able to go back to the raw data and understand why the results change when one does what Foote and Goetz do.5 COMMENTS » Posted by Steven D. Levitt @ 2:46 pm on Monday, November 28, 2005 in General
In contrast, economist John R. Lott, a longtime critic of Levitt's theory who came in for a half page of ad hominem abuse in Freakonomics, is feeling better than Levitt is today. He blogged:
Christopher L. Foote and Christopher F. Goetz's paper can be found here. Personally, I think calling this a "programming oversight" is being much too nice. More importantly, everyone who works with panel data knows that you use fixed effects.
My own work concentrated on murder rates, but I also included fixed effects. Donohue and Levitt never provided us with all their data or their regressions and would never answer any questions that we had so I just assumed that they had included fixed effects from the beginning. It would have been nice if they had provided us with this same information years ago.
My own work concentrated on murder rates, but I also included fixed effects. Donohue and Levitt never provided us with all their data or their regressions and would never answer any questions that we had so I just assumed that they had included fixed effects from the beginning. It would have been nice if they had provided us with this same information years ago.
Financial economist and blogger Mahalanobis (Michael Stastny) makes first a technical point about Levitt's reliance on complexity of analysis a then a substantive point about Levitt's understanding of human behavior:
Levitt's response is on his website (see here) where he notes
The part of the paper that Foote and Goetz focus on is one that is incredibly demanding of the data. For those of you who are technically minded, our results survive if you include state*age interactions, year*age interactions, and state*year interactions.
3 interaction variables are necessary to get the right sign and significance? I think that is very technically demanding. In my experience, interaction variables are kitchen sink type regressors that induce severe multicollinearity and give spurious results. It's like an economist saying his results only appear after doing 3-stage least squares. I have to think something's not really there if you can't normalize the data somehow and show in a simple graph that the pattern is there (in this case, say, by showing the change in arrest rates for abortion and non-abortion states for the relevant age cohort).
I'm partial to the opposite theory, that abortion would, if anything, increase the proportion of evil-doers: abortion is more common among forward-thinking moms who would be good moms, less common among bad moms who view life as a series of random events that happen to them.
I'm partial to the opposite theory, that abortion would, if anything, increase the proportion of evil-doers: abortion is more common among forward-thinking moms who would be good moms, less common among bad moms who view life as a series of random events that happen to them.
The reason that in Levitt's theory of American crime trends, Levitt cites only foreign studies claiming that women who have abortions would make less organized and effective mothers than the ones who went ahead and had their children is because the American studies of who gets an abortion came to the opposite conclusion.
This undermines Levitt's only argument these days about how abortion would cut crime (now that Levitt has hushed up his earlier racial eugenic/eucultural argument that because more blacks get abortions and more blacks commit murders, more abortions should mean fewer murders). These Americans studies were pointed out to Levitt by CCNY economist Ted Joyce in his response to Levitt & Donohue in the Journal of Human Resources, which was entitled "Did Legalized Abortion Lower Crime?" Joyce summed up two reason(s) why Levitt's theory didn't work. The second was:
This undermines Levitt's only argument these days about how abortion would cut crime (now that Levitt has hushed up his earlier racial eugenic/eucultural argument that because more blacks get abortions and more blacks commit murders, more abortions should mean fewer murders). These Americans studies were pointed out to Levitt by CCNY economist Ted Joyce in his response to Levitt & Donohue in the Journal of Human Resources, which was entitled "Did Legalized Abortion Lower Crime?" Joyce summed up two reason(s) why Levitt's theory didn't work. The second was:
"Second, analysts, I being one, have tended to overestimate the selection effects associated with abortion. A careful examination of studies of pregnancy resolution reveals that women who abort are at lower risk of having children with criminal propensities than women of similar age, race and marital status who instead carried to term. For instance, in an early study of teens in Ventura County, California between 1972 and 1974, researchers demonstrated that pregnant teens with better grades, more completed schooling, and not on public assistance were much more likely to abort than their poorer, less academically oriented counterparts (Leibowitz, Eisen, and Chow 1986).
"Studies based on data from the National Health and Social Life Survey (NHSLS) and the National Longitudinal Survey of Youth (NLSY) make the same point (Michael 2000; Hotz, McElroy, and Sanders 1999). Indeed, Hotz, McElroy, and Sanders (1999) found that teens who abort are similar along observed characteristics to teens that were never pregnant, both of whom differ significantly from pregnant teens that spontaneously abort or carry to term.
"Nor is favorable selection limited to teens. Unmarried women that abort have more completed schooling and higher AFQT [the military's IQ test for applicants for enlistment] scores than their counterparts that carry the pregnancy to term (Powell-Griner and Trent 1987; Currie, Nixon, and Cole 1995).
"In sum, legalized abortion has improved the lives of many women by allowing them to avoid an unwanted birth. I found little evidence to suggest, however, that the legalization of abortion had an appreciable effect on the criminality of subsequent cohorts."
"Studies based on data from the National Health and Social Life Survey (NHSLS) and the National Longitudinal Survey of Youth (NLSY) make the same point (Michael 2000; Hotz, McElroy, and Sanders 1999). Indeed, Hotz, McElroy, and Sanders (1999) found that teens who abort are similar along observed characteristics to teens that were never pregnant, both of whom differ significantly from pregnant teens that spontaneously abort or carry to term.
"Nor is favorable selection limited to teens. Unmarried women that abort have more completed schooling and higher AFQT [the military's IQ test for applicants for enlistment] scores than their counterparts that carry the pregnancy to term (Powell-Griner and Trent 1987; Currie, Nixon, and Cole 1995).
"In sum, legalized abortion has improved the lives of many women by allowing them to avoid an unwanted birth. I found little evidence to suggest, however, that the legalization of abortion had an appreciable effect on the criminality of subsequent cohorts."
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Part 3: Abortion and crime: So, Levitt was wrong. But, what actually happened?
Now that Freakonomics author Steven D. Levitt's mishandling of his abortion-crime data has been exposed by economist Christopher Foote, I'd like to review what actually happened in American over those decades.
As I tried to explain to Dr. Levitt when we debated in Slate in 1999, what happened, simplifying greatly, was that the vast youth crack crime wave first emerged in the later 1980s in the socially liberal states where legal abortion also had taken off first about 17 years earlier, most notably New York and California, which legalized abortion in 1970, three years before Roe v. Wade.
In other words, contrary to Levitt's theory, there was at the state level, a positive correlation (when appropriately weighted by population of state), between the legal abortion rate in the early 1970s and the teen homicide offending rate in the late 1980s and early 1990s among those youths born after legalization. Unfortunately, Dr. Levitt initially only looked at crime rates for the years 1985 and 1997 (and only looked at the uselessly crude age groups of over and under 25), so he completely missed how his theory had catastrophically failed its most obvious historical test.
Second, and also contrary to Levitt's theory, this vast youth murder wave took off first specifically in the demographic group that had the highest legal abortion rate: urban blacks. The non-white abortion rate peaked in 1977, well before the peak of the white abortion rate. The peak years for homicide among 14-17 year old black males were 1993 and 1994 -- i.e., the cohort born at the peak of the black usage of legal abortion in 1977. As Donohue and Levitt wrote in 2001, under their theory, the opposite was supposed to happen:
As I tried to explain to Dr. Levitt when we debated in Slate in 1999, what happened, simplifying greatly, was that the vast youth crack crime wave first emerged in the later 1980s in the socially liberal states where legal abortion also had taken off first about 17 years earlier, most notably New York and California, which legalized abortion in 1970, three years before Roe v. Wade.
In other words, contrary to Levitt's theory, there was at the state level, a positive correlation (when appropriately weighted by population of state), between the legal abortion rate in the early 1970s and the teen homicide offending rate in the late 1980s and early 1990s among those youths born after legalization. Unfortunately, Dr. Levitt initially only looked at crime rates for the years 1985 and 1997 (and only looked at the uselessly crude age groups of over and under 25), so he completely missed how his theory had catastrophically failed its most obvious historical test.
Second, and also contrary to Levitt's theory, this vast youth murder wave took off first specifically in the demographic group that had the highest legal abortion rate: urban blacks. The non-white abortion rate peaked in 1977, well before the peak of the white abortion rate. The peak years for homicide among 14-17 year old black males were 1993 and 1994 -- i.e., the cohort born at the peak of the black usage of legal abortion in 1977. As Donohue and Levitt wrote in 2001, under their theory, the opposite was supposed to happen:
"Fertility declines [following the legalization of abortion] for black women are three times greater than for whites (12 percent compared to 4 percent). Given that homicide rates of black youths are roughly nine times higher than those of white youths, racial differences in the fertility effects of abortion are likely to translate into greater homicide reductions."
When William Bennett was denounced for mentioning on the radio the racial logic of Levitt's theory, Levitt tried to give the impression to journalists that race had never played an important role in his theory. Indeed, in Slate.com, William Saletan blamed me for giving Bennett the impression that Levitt was thinking about race. As Ross Douthat rebutted, the racial element in Levitt's theory was prominently played up in the national media even before my debate with Levitt.
But, as I tried to explain to Levitt in 1999, his racial eugenic /eucultural logic hadn't worked. Instead, among black males born in the late 1970s, their murder rate as 14-17 year olds was four times higher than among black males born in the late 1960s, before the legalization of abortion. The black to white teen murder rate ratio almost doubled after legalization. So, the Levitt-Donohue theory failed its first two historical tests in a disastrous fashion.
Then, two things happened historically that helped create the state-level negative correlation (presumably, assuming Foote's new technical critique doesn't completely eliminate it) between later 1970s abortion rates and later 1990s crime rates that Levitt and Donohue have emphasized so repeatedly, while trying to cover up the earlier negative correlation. (They imply that the longer the time lag between presumed cause and effect, the more trust we should put in it!)
1. From NY and CA, crack spread to more socially conservative states, where the abortion rate had also gone up later. So crime was higher in the mid to late 1990s in socially conservative states where abortion rates didn't go up until the late 1970s or early 1980s.
2. And, the crack wave burned out first in the places where it started first, most famously New York City.
We've all heard a million arguments about why crime fell in NYC in the 1990s, but an overlooked explanation was brought up by Knight-Ridder reporter Jonathan Tilove recently: there are today in NYC, 36% more black women alive than black men. Nationally, among all races, there are 8% more women than men alive.
Obviously, this gigantic black male shortage in NYC wasn't caused by abortion -- there was virtually no sex selective abortion at the time. No, it was mostly caused by an enormous increase in imprisonment and by the most dangerous black men murdering each other in large quantities in the late 1980s and early 1990s. (AIDS played a role too.) Levitt has never written, as far as I know, about the impact of these "selective post-natal abortions," as it were, on the crime rate, but it's clearly a substantial factor in a number of big cities that were hit hard by crack. (NYC is by no means unique in terms of the current black male shortage.)
Moreover, as I pointed out to Levitt in 1999, and as his deservedly famous chapter in "Freakonomics" on how dealing crack pays so badly confirmed, a lot of the next cohort of urban youths, those born more than a half decade after abortion was legalized in their state, figured out that dealing crack was a stupid career choice. Seeing how their older brothers and cousins were winding up in prisons, wheelchairs, and cemeteries, they became less likely to commit murder. Participating in the crack wars turned out to be, for the vast majority of the gangstas, extremely bad life choices, and it's hardly surprising that the later cohort born in the early 1980s did a better job of figuring this out.
But these anti-crime trends in the 1990s happened first where crack happened first, which tended to also be where legal abortion happened first, thus creating the most likely spurious correlation between legal abortion and the crime decline in the later 1990s that Freakonomics focuses upon.
So, for this controversy, the crucial issue is The Burden of Proof. Dr. Levitt has tried hard to hand the burden of proof off to his skeptics, claiming that he's looked at all other possible causes of the 1990s crime decline, and they aren't adequate to explain it, so abortion must be the cause of the remainder. That's a weak and irresponsible argument.
Then, two things happened historically that helped create the state-level negative correlation (presumably, assuming Foote's new technical critique doesn't completely eliminate it) between later 1970s abortion rates and later 1990s crime rates that Levitt and Donohue have emphasized so repeatedly, while trying to cover up the earlier negative correlation. (They imply that the longer the time lag between presumed cause and effect, the more trust we should put in it!)
1. From NY and CA, crack spread to more socially conservative states, where the abortion rate had also gone up later. So crime was higher in the mid to late 1990s in socially conservative states where abortion rates didn't go up until the late 1970s or early 1980s.
2. And, the crack wave burned out first in the places where it started first, most famously New York City.
We've all heard a million arguments about why crime fell in NYC in the 1990s, but an overlooked explanation was brought up by Knight-Ridder reporter Jonathan Tilove recently: there are today in NYC, 36% more black women alive than black men. Nationally, among all races, there are 8% more women than men alive.
Obviously, this gigantic black male shortage in NYC wasn't caused by abortion -- there was virtually no sex selective abortion at the time. No, it was mostly caused by an enormous increase in imprisonment and by the most dangerous black men murdering each other in large quantities in the late 1980s and early 1990s. (AIDS played a role too.) Levitt has never written, as far as I know, about the impact of these "selective post-natal abortions," as it were, on the crime rate, but it's clearly a substantial factor in a number of big cities that were hit hard by crack. (NYC is by no means unique in terms of the current black male shortage.)
Moreover, as I pointed out to Levitt in 1999, and as his deservedly famous chapter in "Freakonomics" on how dealing crack pays so badly confirmed, a lot of the next cohort of urban youths, those born more than a half decade after abortion was legalized in their state, figured out that dealing crack was a stupid career choice. Seeing how their older brothers and cousins were winding up in prisons, wheelchairs, and cemeteries, they became less likely to commit murder. Participating in the crack wars turned out to be, for the vast majority of the gangstas, extremely bad life choices, and it's hardly surprising that the later cohort born in the early 1980s did a better job of figuring this out.
But these anti-crime trends in the 1990s happened first where crack happened first, which tended to also be where legal abortion happened first, thus creating the most likely spurious correlation between legal abortion and the crime decline in the later 1990s that Freakonomics focuses upon.
So, for this controversy, the crucial issue is The Burden of Proof. Dr. Levitt has tried hard to hand the burden of proof off to his skeptics, claiming that he's looked at all other possible causes of the 1990s crime decline, and they aren't adequate to explain it, so abortion must be the cause of the remainder. That's a weak and irresponsible argument.
Of course, in reality, he hasn't looked at all the causes -- for example, I've never seen him take into account "selective post-natal abortions" of the most dangerous gangstas by other gangstas, nor the social learning impact on the next cohort of seeing their older brothers die or go to prison.
But, moreover, there's an old saying that large assertions require large evidence. And Levitt's abortion-cut-crime theory is one of the largest assertions in the social sciences in recent years. Clearly, the burden of proof rests on Dr. Levitt.
There's also an old idea in science called Occam's Razor, which more or less says that scientists should be biased toward simplicity in explanations. Throughout this six year controversy, Dr. Levitt has consistently gone for the most complicated, hard-to-understand, and (as we've seen this week, to Dr. Levitt's embarrassment) hard-to-check-up-on statistical models.
In contrast, he's combined statistical incomprehensibility with the most simple-minded behavioral models -- he has repeatedly assumed, despite all the evidence from American studies cited above, that ghetto women decide whether or not to engage in unprotected sex and whether or not get an abortion or have an illegitimate child for the same reasons that would appeal to highly educated women of his own class. While Levitt's style of thinking about how women respond to legalized abortion has proven highly persuasive to the nonfiction book-purchasing class, it doesn't explain much at all about the behavior of the classes in which potential criminals are typically raised. A reader of mine who was an inner city social worker wrote:
But, moreover, there's an old saying that large assertions require large evidence. And Levitt's abortion-cut-crime theory is one of the largest assertions in the social sciences in recent years. Clearly, the burden of proof rests on Dr. Levitt.
There's also an old idea in science called Occam's Razor, which more or less says that scientists should be biased toward simplicity in explanations. Throughout this six year controversy, Dr. Levitt has consistently gone for the most complicated, hard-to-understand, and (as we've seen this week, to Dr. Levitt's embarrassment) hard-to-check-up-on statistical models.
In contrast, he's combined statistical incomprehensibility with the most simple-minded behavioral models -- he has repeatedly assumed, despite all the evidence from American studies cited above, that ghetto women decide whether or not to engage in unprotected sex and whether or not get an abortion or have an illegitimate child for the same reasons that would appeal to highly educated women of his own class. While Levitt's style of thinking about how women respond to legalized abortion has proven highly persuasive to the nonfiction book-purchasing class, it doesn't explain much at all about the behavior of the classes in which potential criminals are typically raised. A reader of mine who was an inner city social worker wrote:
Middle class types see poor unwed teenage mothers as Scum of the Earth and a Terrible Social Problem. But poor women don’t see themselves that way. Instead, they think of themselves as human beings facing the age-old challenge of getting along in the world -- and, if they're lucky, passing their genes on to the next generation.
Maybe the technical opacity of Dr. Levitt's analysis was necessary -- social phenomena are terribly complicated. But the impact of his behavior on the public and on much of his profession has been to encourage among his numerous fans not a critical engagement with the historical and sociological record, but an attitude of faith, a warm feeling that this really smart guy has Figured It All Out using Really Complicated Statistics and we should just take his word for it.
As a marketing strategy, the oracular approach of "Freakonomics" has been mind-bogglingly successful, but perhaps I may be forgiven for wondering whether it advances the cause of good social science.
All the data cited above can be found documented at http://isteve.com/abortion.htm
As a marketing strategy, the oracular approach of "Freakonomics" has been mind-bogglingly successful, but perhaps I may be forgiven for wondering whether it advances the cause of good social science.
All the data cited above can be found documented at http://isteve.com/abortion.htm
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There are lots of charts and graphs in the string posts of posts link. To view them you’ll have to go to http://www.isteve.com/abortion.htm to search for the chart or graph you are seeking.
I am breaking Steve Sailer source link into several parts as I roll along. I am not certain how many actual parts there will be, I may not follow Sailer’s pattern.
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