The global village and our poor estimation of risk

I am reading Risk by Dan Gardner. It is largely about how rubbish people are at estimating risks. This is nothing new, we have had good data how badly we estimate risks for decades. And arguably politicians and marketers have been exploiting it for a lot longer.But the book is well written, and is clear on why we should expect this: because we are the product of evolution.

The idea is that we evolved as a social animal who knew perhaps 100 other people in our local tribe or village. We still have around that many friends, but nowadays the news, and increasingly social media, exposes us to what all 7 billion people on the planet are doing. Now, if your knowledge of the world comes from 100 people, and you learn that one of them is eaten by a crocodile, then it is good way to proceed to assume that your odds of being eaten by a crocodile are around 1 in 100 — which is significant. Thus our brains evolved to focus in and learn from bad scary stuff like being eaten by crocodiles, and then almost instinctively react to seeing a crocodile. It is adaptive to respond strongly to a 1 in 100 chance of death.

This looks like a perfectly well adapted way to survive. But it relies on you only getting scary information from 100 people. When you get the news from 7 billion, then the simple heuristic: remember scary thing then react instinctively, does not work very well. Or rather it works all the time. With 7 billion people around, people are dying in all sorts of ways, some of which are extremely rare. I could learn of, and be scared by, someone being eaten by crocodile tomorrow. But I would have to spectacularly unlucky to die this way in the UK.

In some sense, there is nothing to be done about this, this is all hard-wired into our brains. We are more-or-less physically incapable of ignoring this sort of information. But we can try and stop and think, well if one guy met his end in this memorable way, than if it is only one guy, the odds of me following him is about 1 in 7 billion. Those are pretty good odds. We should try and relax and not worry about those sorts of risks.