Are election polling misses becoming more prevalent? Are they more likely in some contexts than others? Here we undertake an over-time and cross-national assessment of prediction errors in pre-election polls. Our analysis draws on more than 30,000 national polls from 351 general elections in 45 countries between 1942 and 2017. […] Read more »
News Changes Fast, but Polls Keep Snapping Back Into Place
There are still 243 days until the midterm elections. There’s plenty of time for events to reshape the race for control of Congress. But despite plenty of developments over the previous 243 days — with seemingly endless mobile news alerts and presidential tweets — it is hard to say that […] Read more »
House 2018: 26 Ratings Changes, All in Favor of Democrats
Amazingly enough, the special election in Pennsylvania’s 18th Congressional District now looks like a Toss-up. That’s one of 26 House ratings changes we’re making this week, all in favor of Democrats. Republicans are very much in danger of losing a district that supported President Trump by 20 points less than […] Read more »
The States Where Democrats Are Overperforming Most — And Least — In Special Elections
… Special election results so far this cycle are among the clearest portents of a Democratic wave in November. Democrats are beating their usual percentages of the vote not only in special federal elections (i.e., for the U.S. Senate and House), but also in special state legislative elections. … But […] Read more »
How Much Can Primaries Predict the General Election?
The 2018 elections formally begin with the Texas primary on Tuesday, and early voting tallies are already being interpreted as yet another sign of Democratic strength heading into the midterms. … In terms of this year’s midterm elections, there are two ways to look at the primaries: at the national […] Read more »
NOVA: Prediction by the Numbers
Predictions underlie nearly every aspect of our lives, from sports, politics, and medical decisions to the morning commute. With the explosion of digital technology, the internet, and “big data,” the science of forecasting is flourishing. But why do some predictions succeed spectacularly while others fail abysmally? And how can we […] Read more »