538 model & poll tracker thread

[The Other Castro]

It seems at though the Survey Monkey polls were suddenly removed from the averages.

Good.

[GeorgiaModerate]

https://twitter.com/NateSilver538/status/1309275337138864138

[Interlocutor is just not there yet]

It seems at though the Survey Monkey polls were suddenly removed from the averages.

Good.

Yep.

[emailking]

I'm going to go ahead and guess that the Silver truthers in this thread didn't read his book.

[Fmr. Gov. NickG]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

[American2020]

https://twitter.com/NateSilver538/status/1309490650090528768

[Fmr. Gov. NickG]

https://twitter.com/NateSilver538/status/1309490650090528768

Almost everyone has believed this scenario was much more likely for a long time.

https://talkelections.org/FORUM/index.php?topic=393530.msg7568190#msg7568190

[Skill and Chance]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

[GeneralMacArthur]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

I don't think the bounces are meant to last that long, where have you seen that?  The tightening in mid-August was because Trump was getting an RNC bounce and Biden wasn't getting a DNC bounce.

[Gass3268]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

Silver has also said that the time becomes an increasing major component after Labor Day. So Biden being above or near 50% in most of the major swing states and up ~7 nationally, it gets harder for Trump to make a comeback.

[Fmr. Gov. NickG]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

I don't think the bounces are meant to last that long, where have you seen that?  The tightening in mid-August was because Trump was getting an RNC bounce and Biden wasn't getting a DNC bounce.

It does seem like the model is still adjusting all of Trump's polling averages down by about a half point to compensate for assumed residual convention bounce.

[Landslide Lyndon]

Today we had polls showing Biden ahead by 10, 9, and 8 points, and the needle remained stuck at 7.1. I guess Silver's model doesn't consider them as high quality as HarrisX and Rasmussen.

[Sorenroy]

Today we had polls showing Biden ahead by 10, 9, and 8 points, and the needle remained stuck at 7.1. I guess Silver's model doesn't consider them as high quality as HarrisX and Rasmussen.

Today's USC Dornsife poll replaced yesterday's. +9.5 to +10, a half point change on a B/C rated pollster.

Today's Redfield & Wilton Strategies poll replaced last week's. +7 to +9, a two point change on an unrated pollster.

Today's Ipsos poll replaced last week's. +9 to +8, a one point decline on a B- rated pollster.


So three new low- to mid-grade national polls showing minor or even negative changes get fed into a trendline with dozens of other polls from dozens of other pollsters. The model did exactly what you should expect it to do.

[Smash255]

Today we had polls showing Biden ahead by 10, 9, and 8 points, and the needle remained stuck at 7.1. I guess Silver's model doesn't consider them as high quality as HarrisX and Rasmussen.

Today's USC Dornsife poll replaced yesterday's. +9.5 to +10, a half point change on a B/C rated pollster.

Today's Redfield & Wilton Strategies poll replaced last week's. +7 to +9, a two point change on an unrated pollster.

Today's Ipsos poll replaced last week's. +9 to +8, a one point decline on a B- rated pollster.


So three new low- to mid-grade national polls showing minor or even negative changes get fed into a trendline with dozens of other polls from dozens of other pollsters. The model did exactly what you should expect it to do.

In addition state polls feed more into the national poll averages than the national polls themselves do.

[Smash255]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

I don't think the bounces are meant to last that long, where have you seen that?  The tightening in mid-August was because Trump was getting an RNC bounce and Biden wasn't getting a DNC bounce.

It does seem like the model is still adjusting all of Trump's polling averages down by about a half point to compensate for assumed residual convention bounce.

This part is true.  The amount of the adjustment depends on the amount of polls and when.  A state that had a bunch of polls in early September and only a couple in the last week or so will generally have a larger adjustment than a state with a bunch of recent polls.   As more recent polls come out the adjustment gets lessened.   

[Landslide Lyndon]

Today we had polls showing Biden ahead by 10, 9, and 8 points, and the needle remained stuck at 7.1. I guess Silver's model doesn't consider them as high quality as HarrisX and Rasmussen.

Today's USC Dornsife poll replaced yesterday's. +9.5 to +10, a half point change on a B/C rated pollster.

Today's Redfield & Wilton Strategies poll replaced last week's. +7 to +9, a two point change on an unrated pollster.

Today's Ipsos poll replaced last week's. +9 to +8, a one point decline on a B- rated pollster.


So three new low- to mid-grade national polls showing minor or even negative changes get fed into a trendline with dozens of other polls from dozens of other pollsters. The model did exactly what you should expect it to do.

In addition state polls feed more into the national poll averages than the national polls themselves do.

They feed the model, not the polling aggregate.

[Smash255]

Today we had polls showing Biden ahead by 10, 9, and 8 points, and the needle remained stuck at 7.1. I guess Silver's model doesn't consider them as high quality as HarrisX and Rasmussen.

Today's USC Dornsife poll replaced yesterday's. +9.5 to +10, a half point change on a B/C rated pollster.

Today's Redfield & Wilton Strategies poll replaced last week's. +7 to +9, a two point change on an unrated pollster.

Today's Ipsos poll replaced last week's. +9 to +8, a one point decline on a B- rated pollster.


So three new low- to mid-grade national polls showing minor or even negative changes get fed into a trendline with dozens of other polls from dozens of other pollsters. The model did exactly what you should expect it to do.

In addition state polls feed more into the national poll averages than the national polls themselves do.

They feed the model, not the polling aggregate.

Right on the polling page it states national and state polls feed into the aggregate.

[TiltsAreUnderrated]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

I don't think the bounces are meant to last that long, where have you seen that? The tightening in mid-August was because Trump was getting an RNC bounce and Biden wasn't getting a DNC bounce.

538 has written several articles on how they incorporate convention bounces into previous iterations of the model and how they expect them to last 2-3 weeks if not interrupted by another party's convention. If you look at the "nowcast" element of their model (they're not calling it that, but it exists, the adjustments made to Trump's and Biden's polling numbers seem to come from "current events" which I would assume is them attempting to measure the remainders of the convention bounces in the polls they're using.

Adjustments for the RNC bounce will disappear on a state-by-state basis, depending on how quickly state-level polls come out.

[Gustaf]

It’s getting a little bit creepy how stable the model is right now.  Biden has been at 77 for 7 straight days.  It seems like there should be a little movement just by random chance.  I’m surprised Nate isn’t tweeting worries about herding yet.

The model assumes pretty strong convention bounces that last for up to a month.  Next week could be significant as I believe that's when Trump's assumed bounce finally goes to 0.  The narrowing to Biden being only a 2:1 favorite in late August was because the model assumed a DNC polling bounce that didn't really materialize.  I have a feeling it's overweighting the RNC as well and perhaps giving Biden too much credit right now.

I don't think the bounces are meant to last that long, where have you seen that? The tightening in mid-August was because Trump was getting an RNC bounce and Biden wasn't getting a DNC bounce.

538 has written several articles on how they incorporate convention bounces into previous iterations of the model and how they expect them to last 2-3 weeks if not interrupted by another party's convention. If you look at the "nowcast" element of their model (they're not calling it that, but it exists, the adjustments made to Trump's and Biden's polling numbers seem to come from "current events" which I would assume is them attempting to measure the remainders of the convention bounces in the polls they're using.

Adjustments for the RNC bounce will disappear on a state-by-state basis, depending on how quickly state-level polls come out.

They seem to currently be given Biden 0.1-0.2% extra and deflating Trump by like 0.4-0.5% so if polling stays the same Trump should improve a little bit in the model once that rolls off. On the other hand, Trump is getting a lot from the fundamentals-projection part of the model and that should be diminishing fairly quickly by now as we approach election day. So overall if polling doesn't move Trump's chances should be going down.

[Landslide Lyndon]

Right on the polling page it states national and state polls feed into the aggregate.

It must be a mistake. The aggregate moves only with national polls. Just watch it.
OTOH, it's very clear that his model is swayed heavily by state polls.

[Smash255]

Right on the polling page it states national and state polls feed into the aggregate.

It must be a mistake. The aggregate moves only with national polls. Just watch it.
OTOH, it's very clear that his model is swayed heavily by state polls.

This is directly from the national polling page

Polling averages are adjusted based on state and national polls, which means candidates’ averages can shift even if no new polls have been added to this page

[The Mikado]

This is just embarrassing.

40,000 simulations or not, this shouldn't show up if you do 40,000,000 simulations.

[DaleCooper]

This is just embarrassing.

40,000 simulations or not, this shouldn't show up if you do 40,000,000 simulations.

Titanium Tilt R Florida and "Just Not There Yet" Georgia.

[Astatine]

This is just embarrassing.

40,000 simulations or not, this shouldn't show up if you do 40,000,000 simulations.

Titanium Tilt R Florida and "Just Not There Yet" Georgia.

Titanium R Oregon. Fivey Fox took drugs again.

[Dr. Arch]

Two big changes in the 538 model today:

1) Joe Biden finally broke through 77%, and now stands at a whopping 78% chance to win.
2) His median EV performance projection, 331, has now been comfortably above the cone of uncertainty for over a sustained week for the first time. This should shrink further within the next two weeks should polling remain the same or become even more favorable to him.

Statistically speaking, those are big events that shift the probabilities even further in Joe's favor.