-- Niels Bohr
In the aftermath of the election, Hillary Clinton and her supporters have sought to identify the reason(s) for her stunning defeat in the electoral college. FBI Director, James Comey, has received his share of the blame, both from the Clinton campaign ("Hillary Clinton blames one Comey letter for stopping momentum and the other for turning out Trump voters") and the Trump campaign ("Corey Lewandowski Credits FBI Director James Comey With Helping Donald Trump Win").
They could be right, but what I found interesting was how angry Clinton supporters (and perhaps Clinton herself) were at pollsters and modelers for predicting a Clinton win. As absurd as that anger was (as if it really was their fault), there could be a bit of (indirect) truth in it. It is possible that the Clinton campaign grew a bit complacent in the days leading up to the election. Even the least optimistic of the models, FiveThirtyEight's, only gave Trump a 30 percent chance of winning, and this may have provided the Clinton team a false sense of security, which led them to campaign less vigorously than they should have.
As I pointed out in my previous post ("Don't Blame Nate Silver"), a 30 percent chance of winning is actually higher than most people probably realize. If over three consecutive days, weather forecasters predict that there is a 30 percent chance that it will rain, it is very likely that it will rain on at least one of those days. My sense, however, is that Clinton and her supporters interpreted a 70 percent chance of winning as a 100 percent chance of winning, and it may have cost them the election.
All this points to the importance of teaching subjects such as history and statistics. A quick review of presidential election history would show that, on average, polls have been off by about 2 percent, which is pretty close to the spread between the national polls and this year's popular vote. Thus, the Clinton campaign should have known that if the polls were 2 percentage points too high, she could be in deep trouble. And, of course, those with a basic grasp of statistics would know that the models developed by sites such as FiveThirtyEight are probabilistic models. They can tell you the likelihood of future events, but they can't guarantee them. As the Danish physicist, Niels Bohr, once remarked, "prediction is very difficult, especially about the future." Perhaps, that is a lesson all of us can take from this election.