I decided to check on Nate Silver’s California Primary Predictions, this time on the Democratic side.
Once again I find his analysis, and even his math absurd.
Polls-Plus Primary Odds
Somehow Silver magically assign 92% odds of Clinton winning even though recent trends are swinging heavily towards Bernie Sanders. Clinton is still in the lead, but she holds a mere 1 percentage point advantage in the most recent poll.
It’s also ludicrous for Silver to post Sanders’ polling average at 42.9%.
Silver states “Not all polls are created equal, so our forecasts are calculated based on weighted polling averages. The weights account for the quality of each poll based on its track record and its methodological standards. They also account for sample size and how recently it was conducted; recent polls are weighted much more heavily than older ones. Polls are also adjusted for house effects, which is a tendency to consistently show different results for a candidate than the average of other polls.”
I cannot come close to deriving 42.9% except by giving equal weight to polls that Silver rates as being nearly worthless.
Alternatively, and as with Donald Trump in Indiana, Silver simply does not believe the three most recent polls.
Indiana Flashback May 1
On April 24, I commented Another Indiana Poll Goes Trump’s Way But Silver’s Secret Sauce Projects Cruz Will Win.
My comment at the time …
Three successive polls going Trump’s favor should have increased Silver’s confidence Trump would win. After all, repeated polls in national elections all showing Obama with small leads is precisely what led to Silver to call the states correctly.
In this case, Silver clearly believes polls by Fox News, You-Gov, and Public Opinion Strategies are not only biased in favor of Trump, but hugely so.
I don’t buy it, but we don’t know what is precisely in Silver’s secret sauce.
Five Polls Not Enough For Silver
It took six consecutive polls favoring Trump for Silver to change his mind!
This is what the polls looked like on May 1
Despite those polls, Silver projected Cruz had a 65% chance of winning. On May 2 a 6th poll went Trump’s way, and this is what happened: Silver Flushes Secret Sauce Down Toilet, Now Projects Trump has 69% Chance
Silver did not believe five polls in front of his nose! He now apparently does not believe the latest three polls in California.
On April 16, I went out on a limb: Trump Will Win Indiana! This is Why.
I am not going out on a limb like I did in Indiana. But 92% confidence on Clinton is absurd when sentiment and trends shifted towards Sanders. If the next poll or two breaks for Sanders, I do suspect Sanders will win.
Will we see another massive “Silver-swing” in a couple days? I don’t know, but I sure will not be surprised if it happens.
I won’t even be surprises by a Sanders win if the polls stay exactly where they are now. Clearly, Silver would be.
Mike “Mish” Shedlock