Daniel Finkelstein seems to think Islamic terrorism is non-ergodic. He reckons John Mueller (old pdf) understates the probability of an attack:
His argument, the “bloody nuisance” argument, depends on the idea that, without additional measures domestically and internationally, the number of terrorist incidents is unlikely to rise greatly.
There is, however, lots of evidence that crime doesn’t work like that. Instead of falling gently or rising gently in response to policy measures, crime behaves like a contagious disease. Potential offenders catch the idea of offending from each other. And just like a disease that starts with only a few people and becomes an epidemic, once it reaches a tipping point the amount of criminal behaviour explodes.
If successful suicide bombings became even slightly more common, can we really be confident that other fundamentalists would not copy that behaviour?
I'm not sure this analogy works. As my old economics tutor used to ask: what's the mechanism? There are three mechanisms which cause ordinary crime to be contagious which don't apply to suicide bombing:
1. Informational cascades. People copy others if they believe others know something they don't - it's a process of social proof. In the case of ordinary crime, I can see how this works. People see muggers making money without getting caught and infer that mugging is worth doing. And the more such muggers they see, the stronger they'll infer this, and so the more likely it is that they'll become muggers themselves. Being a successful mugger, then, sends a signal to others that mugging is worth doing. Do suicide bombers really send comparable signals?
2. Social norms. If enough people commit crime, their friends and neighbours might do so because the social norm against crime - the censure we'd get from others - breaks down. But although there are many communities of petty criminals, I'm not sure there are communities of suicide bombers, who weaken the social norm against blowing people up.
3. Power laws. Crime soars not merely because more people become criminals but because a few people commit lots of crime. Criminal activity is distributed as a power law (pdf). Here. the analogy with suicide bombing breaks down completely. The good thing about suicide bombers is that none of them is a recidivist.
Whilst I will certainly give you 3), I think 1 and 2 are plausible.
Looking at the fear of being caught vs the perceived paybacks of not being caught, the worst thing that could happen to a suicide bomber is that they are caught before they self-detonate then spend the rest of their life in jail, without the prospect of their glorious martyrdom and with opprobrium (see social norms in 2 above...) heaped on them by the creatures that sent them on their way in the first place.
By this reasoning, the more successful suicide attacks, the weaker the downside appears. As an aside, this is also why it might be important to make such a big song and dance when plans are foiled.
As regards 2), no there aren't "communities of suicide bombers", but there are communities within which those who would become suicide bombers live and are recruited, indoctrinated and trained. It is a valid question as to whether "social norms" apply at all to those who would slaughter others randomly in the name of religion, but then that would suggest that this behaviour is largely unconstrained by social norms in general rather than the breakdown of any existing norm acting an accelerator.
Posted by: The Pedant-General | August 23, 2006 at 02:42 PM
Apparently suicide does enjoy, if that's the mot juste, a copy-cat characteristic. So why not this particular form of it?
Posted by: dearieme | August 23, 2006 at 05:09 PM
But suicide isn't strictly illegal in the UK. When has there been anything reasonably describable as an epidemic of it, which is what you'd expect if Finklestein is correct?
Posted by: jamie | August 23, 2006 at 05:23 PM
With the vast store of authority earned by watching the telly the other night, I can answer jamie with "after the publication of Goethe's Werther". Apparently.
Posted by: dearieme | August 23, 2006 at 05:25 PM
Ah, yes. I remember hearing about that somewhere. Of course, that may be a function of the irrecoverable time they wasted reading it.
Posted by: jamie | August 23, 2006 at 06:51 PM
I followed your link to your economics tutor and was disappointed it didn't lead to ALR Fincham, who you liked to cite in your homework at Wyggy.
I wonder if you would consider signing my petition requesting that the British government provides us with some evidence that these suicide bombers actually existed: http://www.petitiononline.com/j7truth/petition.html
Posted by: cmain | August 25, 2006 at 10:42 PM