House effects, correct calls, and measures of herding

The percentage of correct calls, percentage of calls outside the margin of error, house effect, average distance from polling average (ADPA), and herding penalty for for pollsters with at least 20 polls in the Silver Bulletin database

Note: House effects indicate how a how a firm’s results compare against other polls. ADPA shows how much a pollster’s average poll differs from the average of previous polls of that race. The herding penalty for each pollster is one-half of the difference between a pollster’s actual ADPA and its theoretical minimum ADPA based on sampling error.
Updated February 17, 2025Get the data