8 Comments
Sep 13Liked by Rajiv Sethi

I’ve noticed that there are notable differences among the betting markets. It’s interesting to get some insight as to the differences. Still, why do those differences translate, say, to Predictit consistently, having Haris a larger favorite than.Polymarket?

Also interesting that the Real Clear betting market aggregate has just recently dropped Predictit from their list.

https://www.realclearpolling.com/betting-odds/2024/president

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No excuse at all for dropping PredictIt, seems like they just didn't like the prices. On the other questions, my guess is that the crypto community is generally more optimistic about Trump, or possibly engaging in wishful thinking.

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I've been curious about the difference between the PredictIt and Polymarket numbers, too. Thanks for the additional info.

May not be relevant, but I think Silver has said his current model retains most of the features of the old 538 models he spearheaded. Andrew Gelman had an interesting post looking at strange edge cases in those models during the last election: https://statmodeling.stat.columbia.edu/2020/10/24/reverse-engineering-the-problematic-tail-behavior-of-the-fivethirtyeight-presidential-election-forecast/.

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Thanks for the reminder, I think you're right, the same problem may be at play here

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I think the prediction markets are of questionable value. Recently, during the DNC event, prediction markets had a 90%+ probability that Beyonce will be the surprise guest after an online social media post about a surprise guest. None of this materialized.

In a way, we even have financial prediction markets for interest rate decisions. Even in this market, with significant money at stake, market participants seem to have limited additional knowledge.

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Next debate will be unfavorable to Trump

He gets excited and Harris knows the art of public speaking by calmly exciting the opponent.

Trump is advised to cancel but that will hurt his pride.

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As you said it is too early

As bbc said depends on states on the.magin

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