Thu Oct 12, 2006
Statistics and the Scale of Societies
How many people are murdered in the U.S. every day? How many people die in car accidents every day? How many people die of heart disease in the U.S. in a year? What about the number who die for any reason at all? If you don’t know the answer to these questions, do you have immediate, confident intuitions about what the answers must be?
The Lancet paper by Burnham et al. study estimates about 655,000 excess deaths in Iraq for the period of March 2003 to July of 2006, of which about 600,000 are directly attributable to violence—an appalling number. Right-wing reaction has been, understandably, that the 600,000 estimate is unbelievably high. (Tim Lambert gives a roundup.) Convincing those critics who see this number and declare “that can’t possibly be right,” or “my gut says no” or “this doesn’t even pass the smell test” is difficult. This is partly because some will just think that any estimate that sounds bad must be false, and take refuge in old saws about lies, damned lies, and what have you. But it’s also partly because six hundred thousand violent deaths since the war began seems huge—and, frankly, it is. As this typical guy says, that’s equivalent to 3 to 10 Hiroshima atomic blasts, 6 to 20 Nagasaki atomic blasts or 10 Dresden bombing campaigns. Yes, that’s right. Those events happened in a single day or over a very short period. The present estimate is for a large country of twenty six million people over three and a half years. Sadly, this means it’s quite achievable. As Juan Cole points out, you just have to believe that four our five people a day are being shot or otherwise killed in each of Iraq’s major towns outside of Baghdad.
The incredulous ones will then say, “But that’s about 500 violent deaths a day over the period! Why hasn’t this been reported! So, does this mean all of those headlines of 18 or 30 deaths were off by 700 or so? Inconceivable!” As David Lewis once said, it is hard to know how to refute an incredulous stare. If neither a careful reading of the study itself nor examples like Cole’s will do anything to make you doubt the cognitive power of your bowels, then there’s probably not much to be done. Consider this, though. Even small societies are big. And big societies are huge. Nearly two and a half million people die in the United States every year. Nearly seven hundred thousand people die of heart disease. Lots of things happen that you don’t hear about. I can say with confidence that about a hundred and fifteen people died in road accidents today in the U.S., as did yesterday, and will tomorrow, and the day after that. And about fifty people in the U.S. died today as the result of assault, and will again tomorrow. These numbers are accurate, but I don’t mean them as any kind of serious comparison. They’re just a catalyst for the imagination. Fifty in the U.S., five hundred in Iraq. The two countries are very different, but is it really so inconceivable that ten times as many people might be dying violently on any given day in Iraq than in the United States?