All models are wrong…

… but some are more wrong than others. It’s emerged that a risk calculator for cholesterol-related heart disease risk is giving some highly dubious results. So completely healthy people could start taking unnecessary drugs. It’s not clear if the problem is in the specification or the implementation: but either way, the results seem rather dubious. […]

Unlikely but just about plausible

I’ve been recently been working with the Centre for Risk Studies in Cambridge on some extreme scenarios: one-in-200, or even less likely events. It’s been an interesting challenge, not least because it’s very difficult to make things extreme enough. We find ourselves saying that the step in the scenario that we’re working would never actually […]

Challenge is difficult

We all know that feeling: people are talking about something as if they expect you know what it is, or understand it, and you’re going to look really stupid if you admit ignorance. It’s a common phenomenon in all sorts of fields, not least when technical matters are concerned, as discussed in this article. Not long […]

The big guys don’t always know what they’re doing

You’d think that a really big software company, like Adobe, would know what it’s doing But no. You may have noticed that there was a big data breach: millions of usernames and (encrypted) passwords were stolen. But they were encrypted, so no big deal, right? Ah. Well. That’s the point. As this article explains, it […]

Swiss cheese

Why do things go wrong? Sometimes, it’s a whole combination of factors. Felix Salmon has some good examples, and reminded me of one of my favourite metaphors: the Swiss cheese model of accident causation. In the Swiss Cheese model, an organization’s defenses against failure are modeled as a series of barriers, represented as slices of […]