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Archive of posts filed under the Political Science category.

Election forecasting updating error: We ignored correlations in some of our data, thus producing illusory precision in our inferences

The election outcome is a surprise in that it contradicts two pieces of information: Pre-election polls and early-voting tallies. We knew that each of these indicators could be flawed (polls because of differential nonresponse; early-voting tallies because of extrapolation errors), but when the two pieces of evidence came to the same conclusion, they gave us […]

What if NC is a tie and FL is a close win for Clinton?

On the TV they said that they were guessing that Clinton would win Florida in a close race and that North Carolina was too close to call. Let’s run the numbers, Kremp: > update_prob2(clinton_normal=list(“NC”=c(50,2), “FL”=c(52,2))) Pr(Clinton wins the electoral college) = 95% That’s good news for Clinton. What if both states are tied? > update_prob2(clinton_normal=list(“NC”=c(50,2), […]

Election updating software update

When going through the Pierre-Antoine Kremp’s election forecasting updater program, we saw that it ran into difficulties when we started to supply information from lots of states. It was a problem with the program’s rejection sampling algorithm. Kremp updated the program to allow an option where you could specify the winner in each state, and […]

Now that 7pm has come, what do we know?

(followup to this post) On TV they said that Trump won Kentucky and Indiana (no surprise), Clinton won Vermont (really no surprise), but South Carolina, Georgia, and Virginia were too close to call. I’ll run Pierre-Antoine Kremp’s program conditioning on this information, coding states that are “too close to call” as being somewhere between 45% […]

What might we know at 7pm?

To update our effort from 2008, let’s see what we might know when the first polls close. At 7pm, the polls will be closed in the following states: KY, GA, IN, NH, SC, VT, VA. Let’s list these in order of projected Trump/Clinton vote share: KY, IN, SC, GA, NH, VA, VT. I’ll use Kremp’s […]

Blogging the election at Slate

Slate blog is here. Feel free to place any of your comments at this blog right here.

Recently in the sister blog and elsewhere

Why it can be rational to vote (see also this by Robert Wiblin, “Why the hour you spend voting is the most socially impactful of all”) Be skeptical when polls show the presidential race swinging wildly The polls of the future will be reproducible and open source Testing the role of convergence in language acquisition, […]

What is the chance that your vote will decide the election? Ask Stan!

I was impressed by Pierre-Antoine Kremp’s open-source poll aggregator and election forecaster (all in R and Stan with an automatic data feed!) so I wrote to Kremp: I was thinking it could be fun to compute probability of decisive vote by state, as in this paper. This can be done with some not difficult but […]

Different election forecasts not so different

Yeah, I know, I need to work some on the clickbait titles . . . Anyway, people keep asking me why different election forecasts are so different. At the time of this writing, Nate Silver gives Clinton a 66.2% [ugh! See Pedants Corner below] chance of winning the election while Drew Linzer, for example, gives […]

Modeling statewide presidential election votes through 2028

David Leonhardt of the NYT asked a bunch of different people, including me, which of various Romney-won states in 2012 would be likely to be won by a Democrat in 2020, 2024, or 2028, and which of various Obama-won states would go for a Republican in any of those future years. If I’m going to […]

Kahan: “On the Sources of Ordinary Science Knowledge and Ignorance”

Dan Kahan points me to this paper: It is impossible to make sense of persistent controversy over certain forms of decision-relevant science without understanding what happens in the vastly greater number of cases in which members of the public converge on the best available evidence without misadventure. In order to live well—or just to live, […]

“Trump-Clinton Probably Won’t Be a Landslide. The Economy Says So.”

As I wrote three months ago: Conventional wisdom is that fringe candidates get repudiated, à la 1964 and 1972. The story isn’t so simple. While Hillary Clinton is the consensus of most Democrats, from activists on up to the establishment, Donald Trump is the Republican candidate whom many Republicans want to avoid. . . . […]

Time-Sharing Experiments for the Social Sciences

Jamie Druckman and Jeremy Freese write: We are pleased to announce that Time-Sharing Experiments for the Social Sciences (TESS) was renewed for another round of funding by National Science Foundation. TESS allows researchers to submit proposals for experiments to be conducted on a nationally-representative, probability-based survey research platform. Successful proposals are fielded at no cost […]

Updating fast and slow

Paul Campos pointed me to this post from a couple of days ago in which he wrote: I think it’s fair to say that right now the consensus among elite observers across the ideological spectrum . . . is that the presidential race is over because Donald Trump has no chance of winning — or […]

No evidence shark attacks swing elections

Anthony Fowler and Andy Hall write: We reassess Achen and Bartels’ (2002, 2016) prominent claim that shark attacks influence presidential elections, and we find that the evidence is, at best, inconclusive. First, we assemble data on every fatal shark attack in U.S. history and county-level returns from every presidential election between 1872 and 2012, and […]

“The Warriors suck”: A Bayesian exploration

A basketball fan of my close acquaintance woke up Wednesday morning and, upon learning the outcome of the first games of the NBA season, announced that “The Warriors suck.” Can we answer this question? To put it more precisely, how much information is supplied by that first-game-of-season blowout? Speaking Bayesianly, who much should we adjust […]

Happiness of liberals and conservatives in different countries

Jay Livingston writes: I recall that you have used my post showing that the happiness of conservatives is related to who’s in power. So you might be interested in this multi-nation study showing the same thing: Generally, conservatives are happier than non-conservatives. However, “that is mostly the case in conservative countries. In liberal countries, they […]

The problems are everywhere, once you know to look

Josh Miller writes: My friend and colleague Joachim Vosgerau (at Bocconi) sent me some papers from PNAS and they are right in your wheelhouse. Higher social class people behave more unethically. I can certainly vouch for the jerky behavior of people that drive BMWs and Mercedes in Italy (similar to Study 1&2 in Piff et […]

Colorless green ideas tweet furiously

Nadia Hassan writes: Justin Wolfers and Nate Silver got into a colorful fight on twitter. Nate has 2 forecasts. Nate is doing a polls-only forecast in addition to a “traditional” one that discounts poll leads and builds in fundamentals. Wolfers noted that the 538 polls-only model had Clinton at a higher chance of winning on […]

Authors of AJPS paper find that the signs on their coefficients were reversed. But they don’t care: in their words, “None of our papers actually give a damn about whether it’s plus or minus.” All right, then!

Avi Adler writes: I hit you up on twitter, and you probably saw this already, but you may enjoy this. I’m not actually on twitter but I do read email, so I followed the link and read this post by Steven Hayward: EPIC CORRECTION OF THE DECADE Hoo-wee, the New York Times will really have […]