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David M Rothschild Posted on

In the first academic paper I ever wrote, I compared the performance of poll and prediction market-based forecasts in the 2008 election. Naturally, I described the accuracy of the forecasts, but I also talked about the timeliness of the forecasts. Prediction market data has a lot of added value in that it is always fresh, […]

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David M Rothschild Posted on

Huffington Post’s Pollster does not include the USC/LA Times poll in their general election polling trend, but RealClearPolitics does. And, today, August 20, 2016 the USC/LA Times poll has Republican Donald Trump up 44.2 to 43.6. I do not believe the level of the poll (i.e., the head-to-head value), but I believe there is a lot of […]

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David M Rothschild Posted on

On PredictIt, the price to sell a contract, worth $1.00 if the Democratic candidate wins Pennsylvania and $0.00 if s/he loses Pennsylvania, is $0.79. The price to buy a contract, worth $1.00 if the Democratic candidate wins the election and $0.00 if s/he loses the election, is $0.76. You can sell someone Democrat wins Pennsylvania for $0.03 more than […]

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David M Rothschild Posted on

Throughout the election cycle astute campaign watchers have fixated on a unique polling phenomenon known as social desirability bias. There are answers to questions that are more socially desirable (e.g., I am not a racist v. I am a racist, I recycle v. I do not recycle, and I do not support Donald Trump v. […]

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David M Rothschild Posted on

On Tuesday the Monkey Cage at the Washington Post published an article, “Do betting markets outperform election polls? Hardly.” The article suffers from two common confusions around both prediction markets and forecasting in general. First, election polls are a reflection of the voter intention on the day the poll is taken, while prediction markets are […]

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David M Rothschild Posted on

You sort of know there is a convention bounce that you should sort of ignore, but why? What’s actually in a polling bump? The recent Republican National Convention featured conflict and controversy and one very dark acceptance speech—enlivened by some D-list celebrities (welcome back Chachi!)—but it was still enough to give nominee Donald Trump a […]

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David M Rothschild Posted on

1) There is now a market for whether or not Trump will drop out before August 31. It is trading at about 8% on PredictIt. There is not much traffic yet, and this type of long-shot contract is a little unreliable. But, I will keep a close eye on it. 2) The second thing to […]

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David M Rothschild Posted on

CNN released three polls in July: one right before the Republican National Convention (July 13-16), one between the RNC and Democratic National Convention (July 22-24), and one right after the DNC (July 29-31). The headline number read: 49 Clinton – 42 Trump (Before), 45 Clinton – 48 Trump (Between), and 52 Clinton – 43 Trump […]

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David M Rothschild Posted on

A few thoughts on FiveThirtyEight: 1) Ignoring Polls-Plus: the link on the front-page goes to polls-only, so I am going to cite it as the main forecast. The polls-plus model did worse than the polls-only model in the primary, so I guess they have given up on it. And, it is not OK to pick […]

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David M Rothschild Posted on

I general write about prediction markets or, aggregation of polls and fundamental data, but since we have been running some experimental mobile-based polling and it is extremely timely, I wanted to share the results. The Pollfish survey, a weekly survey of 1,000 American voters, shows a very different trend from the general election polling of […]

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