He's just like Paul Krugman, but with politics

How poor have the election forecasters been this year? It is a topic many are discussing given the large number of upsets we've had during the Primaries. For example, statistician Nate Silver (who started the campaign season proclaiming Trump had Silver then predicted on March 8 with >99% probability that Clinton would win Michigan (she lost). Silver again predicted on May 3 with 90% probability that Clinton would win Indiana (she lost). But there is another issue besides being wrong, which is how much model flip-flopping is occurring just up to these elections. The most proximate example is Silver stating this past Sunday that Cruz had a 65% chance to win Indiana; the next day (Monday, the eve of the election) and with little new data, he "adjusts" that to Trump having a 69% chance to win! That's horrible!

When at first you don't succeed, flip-flop.

Now let's look at the 63 states where Silver has provided a time series of his forecasted winner. We documented each of these states in the map below, separating out those which were/are Democratic races from those that are Republican races. We show the Republican states, in green on the right map below. For 7 of 32 states, Silver completely flipped his opinion on which Republican would win and who would lose that state's primary. We instead color those red. Only in Missouri did we color the state yellow, for a partial flip-flop. Since the initial probability Silver gave to his predicted winner was beyond cut in half (from 14% advantage, to 6%). For Republicans, Silver flip-flops in nearly 1 of 4 states! Any general election poll without flip-flopping could have similar odds for the weaker of the two candidates, and now we cut this forecaster's reliability in half by flip-flopping.

For Democrats, things are about the same too, in the 31 states so far, suggesting that this year's difficulties are not a Trump-only phenomenon. In 4 states (red) we see that Silver completely flip-flopped, and in 3 states (yellow) he at least partially flip-flopped. For Democrats, Silver flip-flopped in nearly 1 of 5 states. Different states too versus those on the Republican party, further suggesting there are serious problems at the core of how Silver and other forecasters are modeling and misleading the public as to their accuracy.

I've got nothing against Nate Silver. It's the worship of him at TOP that bugs the sh*t out of me.