Outlier Poll Results Are Inevitable. They’re Also Sometimes Right.

This afternoon’s New York Times/Siena College poll doesn’t look much like other polls.

It finds Donald J. Trump ahead by six percentage points among registered voters and three points among likely voters nationally. That’s his best result in a reputable national survey in months. You have to go back to a CNN/SSRS poll in April to find something showing him ahead by six points with registered voters. (A Quinnipiac poll today found Trump up by four among registered voters.)

When a poll is considerably different from others, it’s often referred to as an outlier — as it falls outside the range of the other data.

Outliers are no fun for pollsters, but they’re inevitable. Historically, outliers are less accurate when judged against final election results than polls that hew closer to the average of other polls. But outliers often spark a media frenzy — the distinct findings make them seem more surprising or newsworthy. A Selzer/Bloomberg poll from almost this exact date 12 years ago caused a circus when it was released: It showed Barack Obama leading Mitt Romney by 13 points (he won by less than four).

When outlier results come around, it’s generally better to look at the average of polls. As it happens, we released our poll averages for the cycle on Monday: Mr. Trump is ahead by one point over President Biden after including the latest Times/Siena poll. That’s a safer measure of where the race stands.

But that doesn’t necessarily mean the poll should be tossed out altogether. Sometimes, the outliers are right.