Showing posts with label FiveThirtyEight. Show all posts
Showing posts with label FiveThirtyEight. Show all posts

Thursday, August 13, 2020

FiveThirtyEight’s New Election Model Gives Trump A Better Chance Than You Might Think

 The FiveThirtyEight political analytics group has just unveiled its computer model for the 2020 presidential election. As you might expect from a casual glance at the polling, the model favors Democrat Joe Biden, but you might be surprised at how large a chance the model gives Trump of pulling off another upset victory.

The model, which is accessible publicly on the FiveThirtyEight website, differs from polls in that it does attempt to predict an outcome rather than simply recording a snapshot of public opinion at a given time. To do that, the creators of the model take polling as well as a number of other factors into account. For those interested in the nuts and bolts of the project, two of the model’s creators, Nate Silver and Galen Druke, discuss the assumptions of the model on a podcast that you can listen to here.

One important difference between the computer model and traditional polling is that the model takes the Electoral College into consideration. If you merely looked at national polling in 2016, you would have assumed that Hillary Clinton would emerge victorious… which she did in the popular vote. The rub was that Donald Trump eked out a slim victory in a handful of states that allowed him to sway the Electoral College result.

Once the model was built, FiveThirtyEight simulated the election 40,000 times and considered a variety of possible outcomes. The modeling shows that Joe Biden currently has a 72 percent chance of winning the Electoral College. While that reflects a substantial advantage, it does mean that Donald Trump can be expected to win in about one out of every four scenarios, which is a much greater chance than you might think from looking at raw polling data on sites like Real Clear Politics where Biden leads in the polling average by 7.5 points.

“It’s way too soon to count Trump out,” Nate Silver wrote in an accompanying article.

“While the polls have been stable so far this year, it’s still only August,” Silver said. “The debates and the conventions have yet to occur. Biden only named his running mate yesterday. And the campaign is being conducted amidst a pandemic the likes of which the United States has not seen in more than 100 years, which is also causing an unprecedented and volatile economy.”

“Nor has it been that uncommon, historically, for polls to shift fairly radically from mid-August until Election Day,” he added. “Furthermore, there are some reasons to think the election will tighten, and President Trump is likely to have an advantage in a close election because of the Electoral College.”

Currently, the model predicts that Biden will win 324 electoral votes to Donald Trump’s 214. The predicted popular vote outcome favors Biden by a 53-46 percent margin. Joe Biden is also estimated to have a 30 percent chance of a double-digit popular vote victory.

The model also identifies states to watch that are particularly close. These states will not surprise people who have been paying attention to polling thus far. FiveThirtyEight’s battleground states are include North Carolina, Ohio, Arizona, Georgia, Florida, Iowa, Texas, Pennsylvania, and Minnesota. Of those battlegrounds, Biden is forecast to win Minnesota, Pennsylvania, Florida, and Arizona, which would put him over the top in the Electoral College.

Inevitably, the question of 2016 comes up. People ask why polls and models should be trusted when they showed Hillary winning in 2016. The answer is that the failures of 2016 polling have been greatly exaggerated. National polling almost exactly matched the national popular vote. That did not decide the election, however.

State-level polling is always more suspect and variable, especially in close races. In 2016, 13 states were decided by less than five percentage points and state-level polling, in what the American Association for Public Opinion Research called a “historically bad year” in its post mortem of the election polling, had an average error of 5.1 points. This error was attributed to several factors including an actual movement of voters from Clinton to Trump in the last week before the election, an over-representation of college graduates, and the fact that late-deciders broke predominantly for Trump.

Despite the subsequent claims that “everyone” gave Hillary Clinton a 99 percent chance of winning the 2016 election, FiveThirtyEight’s model that year gave Clinton a 71 percent chance of winning, which left Trump with a 28 percent chance of an upset. Ironically, that is almost identical to current odds.

Trump supporters should not be too confident that the president will overcome the odds again, however. Silver points out that much Trump’s chance comes from the fact that the election is still a long way away.

“If we lie to our model and tell it that the election is going to be held today,” Silver says, “It spits out that Biden has a 93 percent chance of winning. In other words, a Trump victory would require a much bigger polling error than what we saw in 2016.”

“We should be clear: Trump’s current position in the polls is poor,” he adds, noting, “Biden is currently ahead in our polling averages in Florida, Wisconsin, Michigan, Pennsylvania, Arizona, Ohio and in the second congressional district in Nebraska — all places that Clinton lost in 2016.”

Trump’s hope is that between now and the election, something will happen to change public opinion and shift the polls in his favor. The pandemic and the associated economic downturn are the largest wild cards for the next few months.

One bit of good news for Trump supporters is that the Electoral College seems to favor Trump again. The model gives Biden a 71 percent chance of winning the Electoral College compared with his 81 percent chance of winning the popular vote.

While the outcome of the election looks dim for Donald Trump in mid-August, a lot can change in the next two-and-a-half months. That’s particularly true in 2020 where it seems that nothing is going normal. Watch the FiveThirtyEight model over the coming weeks to see which way the odds move.

Originally published on The Resurgent

Wednesday, January 9, 2019

Nate Silver: Clinton Campaign Strategists Were 'Huge Dumbasses'

There are many myths about the 2016 election. On the left it is an article of faith that Donald Trump could not have won without illicit coordination with the Russians. On the right, there is the pervasive notion that because Trump beat the odds to win the presidency, all polling is wrong and should be disregarded. Yesterday Nate Silver of FiveThirtyEight managed to blow up both of these theories in a single tweet.

The exchange began with a tweet from Ben Collins of NBC News that asked, “What did the Kremlin's cutouts know about targeting MI and WI? How did they know it? And is there data to show they took action on it?”

Silver, the head of the FiveThirtyEight polling analysis site, responded quickly with a tweet that slammed the door on that particular aspect of Russian collusion. “The 538 model, which was based on publicly-available polling data, said the campaigns should target WI and MI,” Silver wrote. “You didn't have to have any proprietary info to know they were important states. You just had to look at the data and not be huge dumbasses like the HRC campaign was.”

Silver followed up with a link to a FiveThirtyEight article from February 2017, “Donald Trump Had A Superior Electoral College Strategy.” The thrust of the article, subtitled “How Hillary Clinton and the media missed the boat,” was that Hillary made two key errors in the campaign. First, she focused on states where the race was close rather than states that had the potential to tip the race. In particular, the article points out that Clinton did not set foot in Wisconsin after the Democratic primary. Second, she was overconfident and limited her focus to a narrow range of states. Hillary’s main focus was on Florida, North Carolina, and Ohio.

Silver didn’t explicitly address the idea that because the forecasts were wrong in 2016 that all polling is wrong, but it is implicit in his statement that the Clinton campaign was made of “huge dumbasses” who ignored polling data that showed that Hillary was in trouble. Many Republicans claim that the media gave Hillary a 99 percent chance of becoming president on election night, but FiveThirtyEight’s forecast, which is still posted, gave Donald Trump a 29 percent chance of winning. Under those circumstances, Trump was an underdog, but not prohibitively.

With respect to the two states in question, FiveThirtyEight gave Trump a 21 percent chance in Michigan and a 17 percent chance in Wisconsin. Many polls were within the margin of error in Michigan, but Wisconsin polling was further off, showing a consistent albeit single-digit lead for Hillary.

As I pointed out a few months ago, polls are snapshots rather than predictive. One good technique for examining polls is to look for trends in the big picture. The big picture of the polling average from 2016 is still available on Real Clear Politics in convenient graph form. If we look at the trend, we can see Trump plunging in the polls about Oct. 10 then starting a slow rise on Oct. 20. There is a sharp increase between Oct. 28 and Nov. 2 that brought Trump to within two points of Hillary, well within the margin of error of most polls. Going into Election Day, the national polling average had the two candidates about three points apart, a close race by any standard.

If we look at key events that occurred in the campaign, we can see exactly what caused these movements in the polling. Keeping in mind that polls are lagging indicators, we see that Trump’s decline in early October followed the release of the Access Hollywood tape on Oct. 7. The final presidential debate was on Oct. 19 and Trump’s performance seems to have helped him in the polls, but not enough to close the deal. The event that sealed the race in Trump’s favor occurred on Oct. 28, the release of FBI Director James Comey’s memo to Congress that detailed the discovery of thousands of emails that related to the investigation of Hillary Clinton’s private email server. In a May 2017 article, Silver also made the case that Comey’s memo cost Hillary the election.

There are lessons for both parties in Silver’s tweets and articles. For the Democrats, candidates should not take the Rust Belt states for granted. Traditional party loyalties may not be enough to carry a state, especially in an election where everything seems to be going wrong for your candidate. There is no substitute for getting into the field and making appearances. Charisma, broad appeal outside the party, and the stamina to campaign should be factors in nominating a candidate.

For Republicans, the lesson is also that the Rust Belt states should not be taken for granted. Michigan, Pennsylvania, and Wisconsin were all decided by about one percent of the vote after being all but ignored by the Democrat candidate. Just because they voted for Donald Trump once does not mean that they will do so again. The Clinton campaign made mistakes that will probably not be repeated by the next Democratic candidate. Even with these mistakes, however, Trump still lost the popular vote and would most likely have lost the electoral vote had it not been for James Comey. Donald Trump has the stamina to campaign, but he lacks charisma and popularity outside the GOP.

Despite claims from both sides, the 2020 election is far from a sure thing for either party. The outcome will be determined by which side better learns the lessons of the 2016 election and adapts their strategy to a changing electoral environment.


Originally published on The Resurgent