Experts Who Got Brexit Wrong Now Say Trump Can’t Win

Is elite overconfidence surfacing again? Donald Trump says that the same experts and pollsters who incorrectly predicted that British voters would vote to stay in the European Union are now dismissing his chances to win the White House.

That’s mostly true. Before the Brexit vote, PredictWise, a website that aggregates data on the likelihood of events, found that there was a 21 percent chance of its being approved. Early on the night of June 23, when Britons voted, it pinned the chances of Brexit’s passing at only 12 percent. Over...