Bad assumptions, bad math, bad story

Dave Perry, formerly of the Dalhousie Centre for Foreign Policy Studies and the Broadsides website listed in our sidebar links, is now at Carleton University. I know this because his work was recently quoted in an article in The Tyee:

"An estimated 20,000 Canadian Forces members served in the Afghan theatre of operations between 2002 and 31 December 2007, and seven additional six-month rotations will be required between February 2008 and July 2011. Recognizing that 3000 personnel are really required to staff each rotation, by July 2011 there will be approximately 41,000 Canadian military veterans of Afghanistan."

Perry also cites an estimate that "27 per cent of Kandahar veterans will experience mental health problems, including post-traumatic stress disorder, significant depressive issues, and hazardous drinking behaviour. With a total of 11 rotations or 33,000 troops required to fulfill our combat role in Kandahar, this suggests almost 9000 forces personnel may experience some form of mental health problems."

This is disappointing.

The math only works if the CF is sending new people in each rotation. But we all know that's not the case - there are many soldiers serving their second, third, even a few fourth tours in Afghanistan right now. So Perry's 41,000 number is inflated. How much, I don't know. But I suspect by a five-digit margin.

Of course, that's just a guess on my part. But at least I'll tell you I can't vouch for the accuracy of my guess. One would hope you'd get better from an academic writing in "Canada's pre-eminent scholarly publication on international relations." Let alone from an "independent daily online magazine" which one would hope would apply a modicum of common sense to the material it reports.

Update: Dave and I have corresponded in the past about some much better work of his, and he dropped me an e-mail about this piece.

A few comments re my math.

First, so far as I know of, no estimate has been released publically that estimates the number of actual Afghan vets (versus individual deployments) so arriving at an actual number is guesswork unless DND a) knows the real number, and b) will release it.

I suspect they don't even know, but that’s a guess.

That goes for the research I was doing, as well as the PBO report, which was similarly unable to obtain real data from DND.

Second, despite what I just wrote, a year ago, Gen Gauthier, I think it was, testified before one of the defence committees that as of Feb 2009, Canada would have 30,000 Afghan vets. He didn't specify if he meant total rotations, or individual veterans, so I didn't use that figure.

However, for the sake of argument, if we take those numbers...

I don't know how many guys are on more than their first tour, but the five rotos after Feb 2009, (until July 2010, ignoring however many stay past then) will require at least 15,000 individual-soldier-deployments.

So, even if only 2/3 of them are on their first deployment, when added to the estimate of 30,000 vets by Feb 2009, a total estimate of 41,000 is reasonably close.

Third, the 3,000 per rotation number is now too low because our "official" number of deployed has gone up to 2,830, so I'd guess that the numbers required to staff that have increased to something like 3200-3300, but that's a guess.

Fourth, although the 41k estimate may be off, the long term costs of care figures actually start getting worse when you apply them to guys with multiple tours. All the US data shows marked increases in rates of PTSD and other stress injuries as the number of multiple tours goes up.

The 27% incidence rate of operational stress injuries were taken from a post-op analysis of the first battlegroup that went to Kandahar - ie guys on their first tour (in Kandahar). I suspect that rates are going to be much higher for Warrant Officers coming back from their 5th tour.

In any event, at the time I was writing this, no one had done any significant work on this topic, so my goal was to get something out in the public domain, about be as transparent as possible about my methodology, so people could do exactly what you did, and take a look for themselves, and see if it made sense.

I replied that starting with Gauthier's 30,000 comment was iffy, especially if you don't know what it refers to. And that anecdotally at least, more than a third of those in Kandahar have had a tour in Afghanistan before. And that anything higher than the authorized strength is filled with TAV's which aren't as long as a full tour. And that if the 27% figure for OSI is taken from TF Orion and Ian Hope's BG, then you really can't extrapolate from that for a few reasons: the Kabul rotos won't be comparable to Kandahar rotos, the Battle Group figures will be higher than the figures for the entire rotation including all those who go to Kandahar and rarely if ever step outside the wire, and TF Orion involved a different type of combat than subsequent rotos (Medusa was different, as was every other rotation from the next - each had its own patterns of operations).

I told Perry I wish that his speculative numbers had been expressed as speculative, and he responded with a couple of defensible points. First, he was trying to "get something out in the public domain" and provoke some discussion. I'm not a fan of putting out speculation just to provoke a response, but I can see what he's driving at. The fact that we can't get this information directly from government itself, but rather have to piece it together ourselves with limited resources is a problem. Second, he already had to cut about 3,000 words and 30 footnotes out of the piece at the request of the International Journal, his publisher. How can you tell a guy to cut footnotes? The legitimacy of the source data and information is just as important in assessing the veracity of the conclusions drawn as the logic of the reasoning is. So cutting footnotes is simply counterproductive, but not Perry's fault.

I don't know about the rest of the figures in the piece, but the numbers on OSI still seem flimsy to me. That The Tyee didn't contact Perry before writing the article seems flimsy as well, since their piece lacked any additional context he could have provided.

The big problem is that the government isn't providing anything more solid, so flimsy speculation is all we get.