The Price of Bad Polling

The 2020 polling autopsies are still being written, and there are many unanswered questions: How did Republicans win 27 of 27 House districts identified as tossups by the Cook Political Report? How did Sen. Susan Collins win Maine by nine points when she didn’t lead in a single major poll for months? How are President Trump and Joe Biden separated by a little under four points in the national popular vote when Nate Silver’s FiveThirtyEight average showed an 8.4-point Biden lead on Election Day?

The NYU economist Arpit Gupta…