While commentators led by no less than President Obama have blamed violent crime on “the entire generation of young men in our society” and have warned us to fear young black men in particular, those Americans more thoughtful than politicians running for office, exploitative interest groups, sensationalist reporters, and racist fear-mongers know that “entire generations” don’t commit violence; individuals do.
If the individual approaching you is a black teenaged male, how much more likely are you to be attacked and killed by him, as opposed to (say) a middle-aged white man? George Zimmerman may not have been interested, but for those risks we can assess, the danger can be estimated mathematically.
To maximize numbers in this example, I use murders rather than homicide arrests (notoriously incomplete). In the most recent year, 2008, the murder rate of black male teens age 15 – 19 (62.5 per 100,000 population) was 20 times higher than that of white, non-Latinos age 55 – 64 (3.1 per 100,000 population).
So, should we, like Zimmerman, be terrified at the proximity of a random African American 17-year-old? 20 times more fearful than of 55 year-old white person, in fact? Not even nearly. That’s a popular miscalculation sociologist William Julius Wilson has called “statistical bigotry.”
Look again at the measure… murders per 100,000 population. Murder is a very rare event. It is common, not rare, characteristics that define a population. In this case, the common characteristic is “not murderous.”
In 2008, 99,937.5 of every 100,000 black male teens were not murdered, compared to 99,996.9 white middle agers. To correctly calculate the “odds ratio” of murder by a black teen as opposed to a middle-aged white, subtract the “murder population” divided by the “non-murder population” for white male middle-agers (3.1/99,996.9) from that of black male teens (62.5/99,937.5). The result (0.00063 — 0.00003) is that one’s odds of murder by a black teen averages 0.0006 (6 in 10,000) more than by a white middle-ager over a year’s time.
There is, statistically, no more reason to fear the black teenager will kill you, unless you plan on living at least 1,500 years and are immune to dying from anything else. To correctly characterize 99.994% of black teenagers, Mr. President and pundits, call them “a generation that respects life,” and maybe the George Zimmermans will come to see them that way as well.