I have been thinking about the turnover of restaurants in Birmingham recently. There have been a number of new launches in the city in the last year, from Adam’s, with Michelin starred Adam Stokes, to Café Opus at Ikon to Le Truc, each replacing struggling previous ventures.

Nassim Nicholas Taleb makes the case, in his book Antifragile, for the antifragility of restaurants. As he says: Restaurants are fragile, they compete with each other, but the collective of local restaurants is antifragile for that very reason. Had restaurants been individually robust, hence immortal, the overall business would be either stagnant or weak, and would deliver nothing better than cafeteria food – and I mean Soviet-style cafeteria food. Further, it would be marred with systemic shortages, with, once in a while, a complete crisis and government bailout. All that quality, stability, and reliability are owed to the fragility of the restaurant itself.

I wondered if this argument could be extended to terrorism, in an equally Talebian sense.

But first, three false premises:

1. Terrorist attack frequency follows a power law distribution.

Following on from my previous post, I thought I had found another power law distribution in Nate Silver’s book The Signal and the Noise. He sets out a graph of the terrorist attack frequencies by death toll. The source of the data was the Global Terrorism Database for NATO countries from 1979 to 2009. I thought I would check this and downloaded an enormous 45Mb Excel file from the National Consortium for the Study of Terrorism and Responses to Terrorism (START). I decided to use the entire database (ie from 1970 to 2011), with the proviso that I would use only attacks leading to at least 5 deaths to keep it manageable (as Nate Silver had done). The START definition of terrorism is that it is only committed by NGOs, and they also had a strange way of numbering attacks which, for instance, counted 9-11 as four separate attacks (I adjusted for this). I then used a logarithmic scale on each axis and the result is shown below. Not even straightish, so probably not quite a power law distribution, it has a definite downward curve and something else entirely happening when deaths get above 500.

In my view it certainly doesn’t support Nate’s contention of a power law distribution at the top end. On the contrary, it suggests that we can expect something worse, ie more frequent attacks with high casualties, than a power law would predict.

So what possible link could there be between terrorism and the demise of the Ikon café (there may be other restaurants where the food served met one of the other definitions of terrorism used by the Global Terrorism Database, ie intending to induce fear in an audience beyond the immediate victims, but not the Ikon)? Well, for one thing, they do have a made up statistic in common:

2. 90% of new restaurants fail within the first year.

This is a very persistent myth, most recently repeated in Antifragile, which was debunked as long ago as 2007. However, new business failures in general are still up at around 25% in the first year, which means the point that the pool of restaurants is constantly renewed by people with new ideas at the expense of those with failing ones remains valid. This process makes the restaurant provision as a whole better as a result of the fragility of its individual members.

3. 90% of terrorist groups fail within the first year.

Now I don’t know for certain whether this conjecture by David Rapoport is false, but given my experience with the last two “facts”, I would be very sceptical that the data (i) exists and (ii) is well-defined enough to give a definitive percentage. However, clearly there is a considerable turnover amongst these groups, and the methods used by them have developed often more quickly than the measures taken to counter them. Each new major terrorist attempt appears to result in some additional loss of freedom for the general public, whether it be what you can carry onto an aircraft or the amount of general surveillance we are all subjected to.

So what else do restaurants and terrorism have in common? What does a restaurant do when public tastes change? It either adapts itself or dies and is replaced by another restaurant better able to meet them. What does a terrorist group do when it has ceased to be relevant? It either changes its focus, or gets replaced in support by a group that already has. However, although individual terrorist groups will find themselves hunted down, killed, negotiated with, made irrelevant or, occasionally, empowered out of existence, new groups will continue to spring up in new forms and with new causes, ensuring that terrorism overall will always be with us and, indeed, strengthening with each successive generation.

The frequency of terrorist attacks, particularly at the most outrageous end, over the last 40 years would suggest that terrorism itself, despite the destruction of most of the people practising it amongst the mayhem they cause, has indeed proved at least as antifragile as restaurants. So, in the same way that we are all getting fed better, more and more people and resources are also being sucked into a battle which looks set to continue escalating. Because the nature of terrorism is, like the availability of pizza in your neighbourhood, that it benefits from adversity.

This suggests to me:

a. that we should rethink the constant upping of security measures against a threat which is only strengthened by them; and
b. that you shouldn’t believe everything you read.