Category key concepts

Selection bias and the perils of data science

According to the Guardian Data Blog, Obama is heading for electoral success, on the basis of a Twitter-based analysis. It’s all very nice to see mapped out, and the use of geocoding is cool (though possibly flawed), but underlying the approach is a massive potential for selection bias. The problem is quite simply this: if […]

Correlation vs Causation (part 1)

I’m a massive fan of the webcomic xkcd. Don’t be surprised if you find me using Randall Munroe’s creative outputs on a regular basis to help me get my point across. It’s easy to find things that correlate in every day life. Cold weather spells correlate with higher fuel bills. The start of the festival […]

What is epidemiology?

Epidemiology is not the study of skin. That might seem a strange statement to make, but a decent proportion of the people I tell about what I do seem to think it is, so I thought I’d clear that up from the outset. In short, it involves the study of patterns of health and disease […]