538 Model Megathread

[Dr. Arch]

Here's the old forecast from 2012. In particular, I miss the explicit "tipping point state" probabilities this time.

The Presidential election of 2012 was easy to model because

(1) it was not an open-seat election
(2) the President was predictable enough and perceived to be neither a spectacular success nor failure
(3) the Parties have little ideological overlap
(4) the States were sharply polarized in their partisan affiliation, and this was stable
(5) there were no new causes and there was no pervasive change in cultural patterns


So look at those factors. (1) An open-seat election usually hinges upon who wins contested primaries and caucuses, and it is often difficult to predict who will win that. Incumbents rarely lose nominating processes, so that leaves  the incumbent in an election usually his to lose.  That does not apply this time, of course. 22nd Amendment.

(2) History will almost certainly rate Barack Obama as an above-average President, even if most people saw him as a mixture of successes and disappointments. He did not expand his coalition as did FDR, JFK, or Reagan. But neither did he make many mistakes. "General Motors is alive and Osama bin Laden is dead" became the unofficial slogan of Democrats in 2012.

OK. Putting an end to the most dangerous economic meltdown in nearly eighty years and whacking the worst anti-American terrorist ever while avoiding scandals and military or diplomatic disasters is one way to get re-elected even if one loses about 20 states by 10% or more in the previous election. Barack Obama should have been re-elected and was.

(3) The 2010 election knocked out the conservative wing of the Democratic Party in the House of Representatives, and the Republican Party has nothing close to a liberal. Ideological choices between candidates are rather stark. Such makes individual choices easy

(4) Barack Obama winning Indiana in 2008 was something of a freak, something that happens when a state has a large industry (recreational vehicles)  whose market can be hit hard by a combination of an economic downturn, a credit crunch, and high gasoline prices, all of which hit in 2008. That is the only big swing in a state that Barack Obama won. The shift of the Deep and Mountain South from D to R between 1976 and 2008 was basically complete, and it now looks irreversible.

Barack Obama did not depend upon freakish conditions that could evaporate quickly to win.

(5) Tea Party? That's the closest thing to social change. There was no great new religious revival to create a new right-wing ascendancy and no leftish populist movement appearing from seemingly nowhere.

So I could come up with a model. First, recognize that seventeen states and the District of Columbia had not voted for any Republican nominee after 1988 and that there was no marked Republican drift in any of them. That's 243 of the 270 electoral votes that one needs for winning the Presidency, nearly 90% of the needed vote. Second, figure that three states had voted  only once for a Republican nominee for President in the same time, and showed no sign of going Republican this time. That's up to 258. That means that either Virginia, Ohio, Florida, or the combination of Colorado and Nevada would win the election/ Some other states?

Obama wasn't going to win Missouri without winning either Ohio or Virginia; he wasn't going to win Indiana without also winning Ohio; he wasn't going to win Arizona without also winning Colorado and Nevada; he wasn't going to win North Carolina without also winning Virginia; he wasn't going to win Georgia without winning Florida, North Carolina, and of course Virginia.  He also wasn't going to win Colorado without also winning Nevada.

So the 2012 election boiled down to four states -- Colorado, Florida, Ohio, and Virginia, any of which would decide the election. Those states are different enough and separated enough that there is no way to make an appeal that could resonate in all four of those states without
shifting America on the whole.

Treat winning any of the four states as  what statisticians call independent events (coin tosses and throws of a die are independent events), and my crude model held that President Obama had one chance in sixteen of losing if each of the states was a 50-50 proposition. I saw President Obama having a 93.75% chance of winning with all four of those states as 50-50 propositions.

We know how the election turned out. Obama was as successful as Mitt Romney had to be lucky in winning all four states.   
 

So what is different this time?

(1) it was not an open-seat election This one is!
(2) the President was predictable enough and perceived to be neither a spectacular success nor failure has done nothing to hurt any Democrat running to be his successor
(3) the Parties have little ideological overlap (and still do)
(4) the States were  remain sharply polarized in their partisan affiliation, and this was is  stable
(5) there were no new causes and there was no pervasive change in cultural patterns(still true)

Donald Trump, having no experience as an elected public official or as a senior military officer , will be the first nominee for President for one of the two main Parties since George H W Bush  who has never won a statewide office (and George H W Bush showed the effect in 1992 and Ford showed the effect in 1976) and has not been a senior officer or a winner of any public office since Hoover in 1928 (Hoover at the least was a Cabinet secretary). If Americans really want a non-politician, then Donald Trump is the choice. Hillary Clinton is trying to run as a "steady hand", "stay-the-course" type.

This is Hillary Clinton's election to lose and potentially Donald Trump's election to lose catastrophically badly.  Should Donald Trump win, he wins on Hillary Clinton's failure to campaign effectively.

Hillary Clinton has more political experience, and it is apparent that she has learned much by being a First Lady. She is linked to the most successful aspects of the Obama Administration (foreign policy) and makes few gaffes on public policy.

At this point, Donald Trump is behind Mitt Romney in consolidating likely votes for himself. Mitt Romney still lost.
 

 

Great analysis

[Dr. Arch]

Here's a map that 538 seems to think is as equally likely as a 270-268 Trump win (according to the ever-excitable Now-Cast):

468 Clinton - 70 Trump (assuming NE-1 and NE-2 for Clinton).

Beautiful. Blue down to the bare bones.

[Dr. Arch]

The Now Model has gone coo coo for Clinton Puffs, giving HRC a 91.5% chance to win the election with all swing states and some lean states going D.

[Dr. Arch]

Nowcast now has Clinton leading in AZ, GA, and SC (!)

Ok, we need an SC poll now. Never thought I would be asking for one in 2016, lol.

[Dr. Arch]

"Now-cast" has HRC at 96.4%, "Polls Only" at 87.5%, and "Polls Plus" at 79.5%. It's looking very promising as election day nears.

Some interesting notes, SD is now at 30% for HRC, while MO is about to flip in the now cast. In Polls Plus, FL is almost at 70% for HRC and NC is nearing 60%, while AZ and GA are in the mid 30s. What are considered to be the traditional swing and lean states are far gone in all models.

[Dr. Arch]

Damn it feels good to be a gangsta

hahaha

[Dr. Arch]

The models are now beginning to converge. Now-cast and Polls-only have been slowly descending to the Polls-plus model numbers, which have been averaging between 75 and 76%.

[Dr. Arch]

Clinton's now below 70 in polls-plus.  The surge is real!

Nate Silver doesn't have a clue. There is no path, let alone a single one that gives a 30% chance.

Come on now...

You need to get more realistic. A large portion of this country despises Trump. Minds are made up. GOP not winning PA, WI, (or NH! )

Wake up! According to the latest polls they are pretty much equally ~hated. Muahaha

Wake up, the vast majority of this country considers Clinton "qualified" and only about a third say that about Trump.

You don't have to be qualified to be a president. Reagan was not qualified.

A president can have a lot of advisers. What a president needs is good judgement and leadership. That's what Trump has and what Hillary lacks.

L-o-L

[Dr. Arch]

Absolutely astounding that fraudster Nate Silver is making Donald Trump not the biggest conman in this election.

So are you still supporting Trump or not?

I wouldn't dream of stopping now. It's time for a New New Deal in the White House, and only one candidate is willing to give it to us.

Wait, why did you hate Bernie so much then?

Not enough xenophobia/fear.

[Dr. Arch]

After he put in those Google polls, especially the DC one, I lost all faith in this model.

[Dr. Arch]

After he put in those Google polls, especially the DC one, I lost all faith in this model.

You are wrong. He wrote an article regarding that and he weights those tracking state polls from google and ipsos not too much.

Yep, but there are so much more of these trash polls being churned out that, even if he weighs them less, they eventually overwhelm the good pollsters, like Monmouth.

[Dr. Arch]

Trump has collapsed tremendously, while HRC surged simultaneously. Let's look forward to Sunday and hope that she seals the deal then.

[Dr. Arch]

McMullin added to the Utah model!

McMullin's color in Utah is McPurple

FTFY

[Dr. Arch]

Clinton's slipped to 86% in the Nowcast, 85% in the polls-only and 81-82% in the polls-plus.

The Senate forecast has shifted to the Democrats (now over 60% in all three models) because Cortez-Masto has taken the lead in Nevada

With the latest polls, she got about a 2% bump again.

[Dr. Arch]

As of this post, AZ is less than 3% points from flipping in polls-plus and over 60% Clinton in the now-cast.

[Dr. Arch]

Trump's been gaining ground every day since the debate. Am I right to be a little nervous?

No, because he hasn't been. Open the model and look at the trend lines before saying such a thing, please.

[Dr. Arch]

I just realized that another model that Nate could use would include early-voting turnout/expectations alongside the factors included in Polls-Plus, something like Polls-Premium?

I would certainly like to see how elements such as the extremely positive turnout in states like FL, TX, and AZ would pull things one way or another. What do you guys think?

[Dr. Arch]

I just realized that another model that Nate could use would include early-voting turnout/expectations alongside the factors included in Polls-Plus, something like Polls-Premium?

I would certainly like to see how elements such as the extremely positive turnout in states like FL, TX, and AZ would pull things one way or another. What do you guys think?

Everything in the model (both polls and the "poll plus" variables) is based on the predictive value of the parameters as established by previous presidential elections.  Has early voting really been around long enough to tell you how much predictive power those things have on the election outcome?  You have to be able to say "X% of the time where this variable says Y, the leading candidate wins."  But if early voting has only been around for one or two presidential elections, then you don't have a large enough sample to be able to say anything.

A fair point. Perhaps several cycles from now, it will be a possibility.

[Dr. Arch]

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In short, no.

[Dr. Arch]

Did anyone else notice that OH flip in 2 of the 3 models? I think that accounts for the % difference. That is really weird considering the polls are extremely good for HRC.

[Dr. Arch]

Trump's chances keep going up, exactly what I was kinda freaking out about a few days ago. First time we've seen a state flip from blue to red since the debate I think.

Also, Ohio is to the right of Arizona. That is so strange

His models has been going towards Trump for a while now even with very positive polls for HRC.

AZ: C+2 [increased for Trump]
GA: Tie [increased for Trump]
Breitbart Nat: C+1 (+1 from their last poll) [increased for Trump]
Pew Nat: C+7 [increased for Trump]

It's doing very questionable movements. I'm not buying it.

[Dr. Arch]

Seeing a Trump fan call him Daddy is the creepiest thing I've seen all week, so thanks for that.

Pretty much.