Wednesday, August 01, 2007
Seasonality in Iraq War Causalties?
by Tom Bozzo
A few observations on top of Farley's:
Robert Farley notes at LGM that the lower U.S. death toll in Iraq for July — 78 as of this morning, at icasualties.org — is being touted as the "year's lowest." Go surge?! In the NYT:
On July 26, Lt. Gen. Raymond T. Odierno, the second-ranking American commander in Iraq, said that the lower death toll was a “positive sign” but that it was too early to say whether the reduction was a “true trend.”Farley makes the needed 'one observation (probably) does not a trend make' comment, and raises the possibility of seasonality in the data. Here's a graph of the icasualties.org tallies by month (for the whole coalition, not just the U.S.):
A few observations on top of Farley's:
- They forgot about Poland: The figure for total coalition casualties for the month (87) is a less-newsworthy fourth-best for the year.
- So far, 2007 looks like 2006, shifted up.
- The July fatality rate (2.81/day) remains above the 2.48/day average for the entire ordeal.
- If someone's popping corks over 78 deaths a month, when the figure has been less than half that as recently as March 2006 (a long time ago, actually), then success clearly is being defined down.
- The seasonality picture is a bit hard to eyeball (unlike, say, the pattern of natural gas usage at my house), though it's pretty uniformly the case that the summer months are never the annual peak. Taking past years as a guide, I'd bet on at least one month to come this year that's considerably worse than the summer trough.
- Like Farley, I'd guess that the non-summer peaks aren't random, though I think it's a matter for future military historians more than X-12 ARIMA to describe the considerations behind the timing of the operational (and hence casualty) peaks.
Labels: Iraq, Statistics
