Predicting abortion attitudes

Quartz has an interesting analysis of a recent Twitter storm over abortion, triggered by the US Republicans’ attempts to defund Planned Parenthood.  The headline is striking “How to tell whether a Twitter user is pro-choice or pro-life without reading any of their tweets.”

The writers describe how they could use words in twitter profiles to predict people’s attitudes.  They also found that social network structure was a very strong predictor: people shared the views of those they followed.  They write “so polarized is the social network structure that even very basic, obvious characteristics stop mattering if we know who your friends are”

It might seem strange that you could do so well in predicting attitudes across multiple countries on a controversial topic. It would be strange, except that the data they used was restricted to a small group of people who were participating in a Twitter argument about abortion. The story admits this, but not until near the end.

In real life, you probably can’t learn that much about someone’s views on abortion by whether they tweet about cats or football. In the context of a small, highly polarised argument, you probably can.  In real life, people don’t necessarily agree with the views of the people they follow on Twitter, but in that context it’s not surprising that they do.  And in real life, if someone wants to find out your views on a controversial topic they’d probably be better off asking you than tracking down all your friends and asking them.