Sociologist defends statistical predictions for elections and other important information

Political polling has come under a lot of recent fire but a sociologist defends these predictions and reminds us that we rely on many such predictions:

We rely on statistical models for many decisions every single day, including, crucially: weather, medicine, and pretty much any complex system in which there’s an element of uncertainty to the outcome. In fact, these are the same methods by which scientists could tell Hurricane Sandy was about to hit the United States many days in advance…

This isn’t wizardry, this is the sound science of complex systems. Uncertainty is an integral part of it. But that uncertainty shouldn’t suggest that we don’t know anything, that we’re completely in the dark, that everything’s a toss-up.

Polls tell you the likely outcome with some uncertainty and some sources of (both known and unknown) error. Statistical models take a bunch of factors and run lots of simulations of elections by varying those outcomes according to what we know (such as other polls, structural factors like the economy, what we know about turnout, demographics, etc.) and what we can reasonably infer about the range of uncertainty (given historical precedents and our logical models). These models then produce probability distributions…

Refusing to run statistical models simply because they produce probability distributions rather than absolute certainty is irresponsible. For many important issues (climate change!), statistical models are all we have and all we can have. We still need to take them seriously and act on them (well, if you care about life on Earth as we know it, blah, blah, blah).

A key point here: statistical models have uncertainty (we are making inferences about larger populations or systems from samples that we can collect) but that doesn’t necessarily mean they are flawed.

A second key point: because of what I stated above, we should expect that some statistical predictions will be wrong. But this is how science works: you tweak models, take in more information, perhaps change your data collection, perhaps use different methods of analysis, and hope to get better. While it may not be exciting, confirming what we don’t know does help us get to an outcome.

I’ve become more convinced in recent years that one of the reasons polls are not used effectively in reporting is that many in the media don’t know exactly how they work. Journalists need to be trained in how to read, interpret, and report on data. This could also be a time issue; how much time to those in the media have to pore over the details of research findings or do they simply have to scan for new findings? Scientists can pump out study after study but part of the dissemination of this information to the public requires a media who understands how scientific research and the scientific process work. This includes understanding how models are consistently refined, collecting the right data to answer the questions we want to answer, and looking at the accumulated scientific research rather than just grabbing the latest attention-getting finding.

An alternative to this idea about media statistical illiteracy is presented in the article: perhaps the media perhaps knows how polls work but likes a political horse race. This may also be true but there is a lot of reporting on statistics on data outside of political elections that also needs work.

Leave a comment