In my last post I displayed a plot showing a striking correlation for single-motherhood rates and out-of-school suspension rates between racial/ethnic groups using national averages.
I am well aware that aggregating linearly correlated variables will tend to produce (much) stronger correlations than you’d see with more granular data (e.g., state, county, family, individual, etc). On the other hand, I am familiar enough with these statistics to know that you will see substantially weaker correlations here with other common predictors. Hispanics/latinos, for instance, tend to be worse off than than blacks by many economic measures, rarely appreciably better off, and yet their discipline problems are much less (even, interestingly, less than whites in California controlling for median family income). Likewise, the distance between asians and non-hispanic whites tends to be modest on economic dimensions, but their suspension rates are roughly half the non-hispanic white average.
For the benefit of others, I decided to generate some plots of predictors aggregated at a national level for comparison’s sake (note: I reversed the x-axis to keep the graphic relationship the same where necessary).
There is, of course, ample evidence that discipline rates vary dramatically between racial/ethnic groups.
Blacks get suspended at vastly disproportionate rates whereas “asians” (census/OMB definition), on the other hand, are about half as likely as whites are to get suspended. Contrary to conventional wisdom, though, this pattern tends to be pretty consistent nation wide and the south is not notably “worse” with respect to disparities here.
Philip Cohen, a sociologist that blogs at Family Inequality, recently argued, in response to the proposition that single-motherhood is strongly associated with economic mobility, that the single-motherhood effect is “entirely in the % black effect”.
While I do not necessarily disagree with the notion that racial demographics are strong predictors (albeit probably for different reasons than he does) and I do not necessarily believe that the single-motherhood association is (mostly) causal, his strong language is clearly at odds with the data. In fact, his statements are not even well supported by his own stats.
Could you do an analysis on racial differences in educational outcomes after controlling for parental education, parental occupation, household wealth, neighborhood wealth, neighborhood education, single parent status, native language etc.? I’ve seen you control for family income and parental education (and occasionally both), but I’ve never seen you control for more beyond that (perhaps I’ve missed something!). In Chapter 16 of Affirmative Action for the RichThe Future of Affirmative Action, Dalton Conley of New York University used the Panel Study of Income Dynamics to show that parental wealth (not income) and parental education are the best predictors of college completion, which means that they may also be good predictors of other educational outcomes. He also discussed the data showing that racial wealth gaps are much larger than racial income gaps, which implies that wealth could account for a larger portion of the achievement gap than income. Could you do a similar analysis for IQ? The reason I’m asking for all this is that Carnevale and Strohl control for all of these factors and are left with a very small race effect: http://www.tcf.org/assets/downloads/tcf-CarnevaleStrivers.pdf
I have heard this bit about wealth before. I am deeply skeptical that wealth can mediate much, if any, of the B-W gap.
Before I dig into this though, let’s take a very brief look at some of the studies Max cited (see here and here) :
In my last post, I plotted the overall US county-level homicide rate (all groups combined) by racial/ethnic demographics. Much of that correlation is being driven by high black-on-black homicide rates throughout the country.
If I plot the rate by the race/ethnicity of the victim this pattern becomes clear and the group-level correlation weaken somewhat (especially asians and whites), but it’s still there…
While I am personally ambivalent about gun ownership and suspect it plays an incremental role in relative differences between countries/regions/etc (holding other things roughly equal), I thought I’d add some perspective into this argument about the presumed causality of gun ownership on homicide rates.
Mother Jones analysis includes gun suicides and makes no attempt to correct for even course-grain racial/ethnic confounds.
I do not feel like doing a lengthy analysis here and now, but suffice it to say that once you remove suicides and race/ethnicity from the equation the case gets much weaker.
There is no evidence of a positive correlation here for blacks and hispanics (if anything somewhat negative).
There is a positive correlation for non-hispanic whites (r=0.45), but it pales in comparison to the racial/ethnic differences here. To put this into perspective, amongst non-hispanic whites (the bulk of the gun owners in most states), states with the highest gun ownership rates have just 1 death per 100,000 more than states with the lowest rates (on average).
The NLSY97 data provides height information for both biological parents and students at yearly intervals, so I thought I’d take a look at that data.
It looks very much like heritability increases with age here (unsurprisingly). Around age 13 the slope is relatively flat, especially for boys, but it slowly increases and by age 21 (give or take) there is a rather stark contrast.