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Bobby Gladd's avatar

Another random “current“ from a subscriber: The other day, I posted a story to my Facebook page, and was shortly thereafter notified by Facebook that, unless I opted out, henceforth all of my story postings would be given an AI generated “headline.“ Supposedly to help gain better visibility for my stories. Read “content monetizing assistance.“ I replied in testy ALL CAPS. (Use your imagination.) Something along the lines of. NO.MUTHA.ZUCKING.WAY…

Nicholas Weininger's avatar

There are real problems with insider trading on prediction markets, but I don't think the "shakedown" framing quite captures them. The debate among economists about regular (stock market) insider trading regulations illustrates why.

Austrian economists have classically argued that insider trading is fine and good and should be legal, because transferring inside information to markets through a trade is good for price accuracy and the market discovery function. The most compelling counterargument, AFAICT, is *not* that insiders profit at the expense of less-informed traders. Those traders are, after all, making uncoerced choices to participate in the market, and if they lose out, that should be their problem.

Instead, the strongest case for banning insider trading is that if you have a fiduciary duty to an institution, and you can make a ton of money by betraying that duty, and everybody knows you can do that, that degrades both the substantive quality of the institution and trust in the institution.

Same for prediction markets. It's not clear that we should care if people who make an uncoerced choice to bet on a political event get "fleeced" by a small minority of better-informed traders. At most that is what economists call a pecuniary externality. But if one of those traders is someone who can influence the political event to the detriment of the public good they're supposed to serve, _that_ we should care about-- it's analogous to a basketball player being able to profit on DraftKings by throwing a game.

A related problem is that if you have enough riding on a bet, and the bet uses some generally accepted public data source as a resolution metric, you have a strong incentive to *become* an insider and affect the outcome of the bet by distorting the data source to the detriment of the general interest in public data accuracy. The recent incident of possible weather station tampering in Paris is a perfect example: https://www.nytimes.com/2026/04/24/world/europe/polymarket-bets-france-paris-temperature-weather.html

All of this ultimately comes back to Goodhart's Law. We will always come up with new metrics to use in trying to improve our lives, and new ways of gaming those metrics, and the tension between the measurers and the system-gamers never ends.

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