It’s Not Just The Math

This week, statistics-driven political forecasting won a big slab of public vindication after the U.S. election predictions of an array of number-crunching analysts turned out to be remarkably accurate. As John Sides said over at the Monkey Cage, “2012 was the Moneyball election.” The accuracy of these forecasts, some of them made many months before Election Day,

…shows us that we can use systematic data—economic data, polling data—to separate momentum from no-mentum, to dispense with the gaseous emanations of pundits’ “guts,” and ultimately to forecast the winner.  The means and methods of political science, social science, and statistics, including polls, are not perfect, and Nate Silver is not our “algorithmic overlord” (a point I don’t think he would disagree with). But 2012 has showed how useful and necessary these tools are for understanding how politics and elections work.

Now I’ve got a short piece up at Foreign Policy explaining why I think statistical forecasts of world politics aren’t at the same level and probably won’t be very soon. I hope you’ll read the whole thing over there, but the short version is: it’s the data. If U.S. electoral politics is a data hothouse, most of international politics is a data desert. Statistical models make very powerful forecasting tools, but they can’t run on thin air, and the density and quality of the data available for political forecasting drops off precipitously as you move away from U.S. elections.

Seriously: you don’t have to travel far in the data landscape to start running into trouble. In a piece posted yesterday, Stephen Tall asks rhetorically why there isn’t a British Nate Silver and then explains that it’s because “we [in the U.K.] don’t have the necessary quality of polls.” And that’s the U.K., for crying out loud. Now imagine how things look in, say, Ghana or Sierra Leone, both of which are holding their own national elections this month.

Of course, difficult does not mean impossible. I’m a bit worried, actually, that some readers of that Foreign Policy piece will hear me saying that most political forecasting is still stuck in the Dark Ages, when that’s really not what I meant. I think we actually do pretty well with statistical forecasting on many interesting problems in spite of the dearth of data, as evidenced by the predictive efforts of colleagues like Mike Ward and Phil Schrodt and some of the work I’ve posted here on things like coups and popular uprisings.

I’m also optimistic that the global spread of digital connectivity and associated developments in information-processing hardware and software are going to help fill some of those data gaps in ways that will substantially improve our ability to forecast many political events. I haven’t seen any big successes along those lines yet, but the changes in the enabling technologies are pretty radical, so it’s plausible that the gains in data quality and forecasting power will happen in big leaps, too.

Meanwhile, while we wait for those leaps to happen, there are some alternatives to statistical models that can help fill some of the gaps. Based partly on my own experiences and partly on my read of relevant evidence (see here, here, and here for a few tidbits), I’m now convinced that prediction markets and other carefully designed systems for aggregating judgments can produce solid forecasts. These tools are most useful in situations where the outcome isn’t highly predictable but relevant information is available to those who dig for it. They’re somewhat less useful for forecasting the outcomes of decision processes that are idiosyncratic and opaque, like North Korean government or even the U.S. Supreme Court. There’s no reason to let the perfect be the enemy of the good, but we should use these tools with full awareness of their limitations as well as their strengths.

More generally, though, I remain convinced that, when trying to forecast political events around the world, there’s a complexity problem we will never overcome no matter how many terabytes of data we produce and consume, how fast our processors run, and how sophisticated our methods become. Many of the events that observers of international politics care about are what Nassim Nicholas Taleb calls “gray swans”—”rare and consequential, but somewhat predictable, particularly to those who are prepared for them and have the tools to understand them.”

These events are hard to foresee because they bubble up from a complex adaptive system that’s constantly evolving underfoot. The patterns we think we discern in one time and place can’t always be generalized to others, and the farther into the future we try to peer, the thinner those strands get stretched. Events like these “are somewhat tractable scientifically,” as Taleb puts it, but we should never expect to predict their arrival the way we can foresee the outcomes of more orderly processes like U.S. elections.

Leave a comment

Leave a Comment

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


Get every new post delivered to your Inbox.

Join 5,709 other followers

%d bloggers like this: