538 model & poll tracker thread

[Figueira]

Maybe he's going to release the Prez, Senate, and House model all at once? Didn't he release them separately in 2016? (at least Prez and then Senate/House later?)

There wasn't a House model in 2016 IIRC. The first House model was in 2018 since that was the focus of everyone's attention that cycle.

[Figueira]

https://projects.fivethirtyeight.com/2020-election-forecast/

Here's the likely link to the forecast

You're probably right--replacing 2020 with 2016 takes you to that forecast, replacing 2020 with other years gets you a 404 error, but the 2020 page is simply blank.

[Figueira]

This map (269-269 tie) is showing up as one of their 100 example maps (which I'm guessing are randomly selected?).

Annoyingly, these maps don't show the separate EVs so you have to infer them based on the numbers, but I'm assuming NE-2 is voting D and ME-2 is voting R here, since their forecast gives NE-2 a higher chance of flipping.

Anyway, definitely not the 269-269 map I would expect.

[Figueira]

LOL, this is one of the maps that showed up on the 100 randomly selected maps.

[Figueira]

It's miniscule but I really dont understand:

Before YouGov poll: Biden +8.3

YouGov poll which has +11 (RV) and +9 (LV) tabs

Biden's lead ticks *down* to 8.2.

How did it tick down when the poll result was *above* the previous average?

Could be that some other poll was removed from the average.

[Figueira]

If you hover over the states in the snake chart you can now see the projected final percentages. Praise!

I don't want to spam this constantly, but here's the current projection:

Edit: Wisconsin

[Figueira]

I don't agree with his assessment. We've had 58 Presidential elections which is nowhere near enough to know how weird things could get if you could run this election 40,000 different ways. Heck just look at 2016 where a single sate Utah is about 20% less Republican than it should be given how the other states went.

These weird scenarios keep coming up in the 100 scenarios that actually show up on the website though.

[Figueira]

346: the number of electoral votes Biden will get?

(I know Arizona going Republican is a little unlikely given the rest of the map, but maybe Biden underperforms with Hispanics.)

[Figueira]

346: the number of electoral votes Biden will get?

(I know Arizona going Republican is a little unlikely given the rest of the map, but maybe Biden underperforms with Hispanics.)

https://twitter.com/AndrewSolender/status/1304979308822265857

What did you think I was responding to?

[Figueira]

ME-2 is now at exactly 50-50.

[Figueira]

ME-2 is now at exactly 50-50.

It looks like it's shaded blue on their snake chart.

Probably it's 50.01% Biden or something like that, but they rounded it to 50. Either that, or they have an algorithm for what color to display if the numbers are equal.

[Figueira]

I've noticed that whenever there's a rounding area causing the percentages to add up to 99 instead of 100, they include a tied map in their 100 randomly selected maps. Seems a little misleading.

[Figueira]

I've noticed that whenever there's a rounding area causing the percentages to add up to 99 instead of 100, they include a tied map in their 100 randomly selected maps. Seems a little misleading.

Isn't a tied map the only reason the %'s wouldn't add up to 100?

I assume that the model isn't literally taking 100 random maps from among all the maps.  If Biden is projected to win 77% of the time, it must always choose exactly 77 maps where Biden is projected to win.  Otherwise, the composition of this sample would fluctuate enormously, as the margin of error for a sample of 100 is around 10%.

Given this, is seems reasonable to deliberately choose exactly one tied map when the tie possibility makes a meaningful difference in the percentages.

Technically yes, but just because the numbers currently don't add up to 100 doesn't mean that the odds of a tie have increased.

And yeah, they are deliberately choosing a number of maps that reflects the current percentage for each candidate. I'm not sure how the algorithm for that works though.

[Figueira]

https://projects.fivethirtyeight.com/2020-election-forecast/

As of this morning, Biden now has a 79% chance.

Looks like it's up to 80 now, at least as I'm looking at it. No jaw-dropping new polls since yesterday - maybe now that the first debate is over and there wasn't a clear Trump win they have uncertainty going down?

Nate said when they launched the model that if they told the model the election was that day, Biden's odds would be above 90%. So if Biden's numbers stay even, we should expect to see his odds increase as we get closer to Election Day.

Anyway, I made a simple swing/trend map from 2016 for the current forecast (at least, current as of a few minutes ago). Red is a Democratic swing and trend, gray is Democratic swing but Republican trend, and blue is Republican swing and trend. If this is accurate, then Biden's popular vote advantage is mostly coming from Republican states, not Democratic states. It's probably not very accurate, but it does make some sense given polls showing Biden doing reasonably well in rural areas.

Edit: fixed Vermont.

[Figueira]

North Carolina is now expected to vote for Biden by exactly the same margin as Ohio (.6%).

[Figueira]

North Carolina is now expected to vote for Biden by exactly the same margin as Ohio (.6%).

This is an effect of OH moving further left on the model, correct?

Yes. Both have been moving left, actually.

[Figueira]

The 538 model no longer projects that Trump winning the popular vote is a possibility. The cone of uncertainty is no longer crossing over the margins of error for each candidate's potential final PV range.

It's a possibility, but it's not within the median 80%. The model currently shows a 10% chance of Trump winning the popular vote. You can see this if you scroll down just below this graph.

[Figueira]

National polls don't affect the overall forecast much.

[Figueira]

WI now shows up as the tipping point state on the snake chart, with PA being more Democratic (although the margins are identical).

[Figueira]

How many times has Iowa switched colors today?

[Figueira]

It's looking like their final performance will be

- 50/53 for the Presidency (NC, ME-2 and FL wrong)
- 30/33 for the Senate (NC, ME and IA wrong)
- ~400/435 for the House (not enough room to list all errors)

An improvement over 2016, but by 2024 it's hard to see them keep their sterling reputation gained in 2012.

Will Nate even care at that point?

In retrospect, 2012 was really more about the polling being pretty close to accurate rather than Nate Silver being any kind of genius. The one state he got right that a lot of people didn't was Florida, but I assume that was just a poll weighting thing.