Disclaimer: I have not read any literature on the economics of prediction markets, and I know nothing about the mechanics of Polymarket/Kalshi.
I would imagine that in theory, everyone thinks they have the best information at the time, something like:
House: "Odds that X happens? We'll put $1 on both sides to get it started. 50/50."
Someone comes along: "Oh dang, I'm definitely more than 50% confident that X is happening. Let me put $1 in." Now it's 67:33.
Someone else comes along: "Oh I'm more than 67% confident X is happening, let me put $1 in." Now it's 75:25.
And of course, you get people going: "I'm more than 25% confident that X is _not_ happening, let me put $1 in!" And now it's 60:40.
The murky part, I would imagine, comes when the odds and the payout actually act as something that influences the outcome, but in perfect theory-land, if everything goes as planned, this should move the odds to the most informationally-accurate measurement, which should, in theory, benefit observers by making this measurement public.
Sure but these things are not really "odds" anymore, right? The most searched terms might be a mystery to the general public, but not to the engineers at Google. It gets even murkier when you can influence the outcome. The exact temperature at an airport might be difficult to predict, but if you are able to hold up a hair drier to the sensor for a few minutes you can be pretty sure it won't be cold.
When the other side either has information that makes it not a bet, or if they have means to influence the odds, the best outcome for outsiders is to not play at all.
And of course, the entire conceit relies on the idea that more accurate information to the public is always good and always outweighs the negative externalities. But is it really all that important to the public good what the most searched artist is on Google in a certain year? Or if an announcer will say a certain word during the super bowl?
I don't think this is entirely true. Polymarket is extremely transparent on user accounts and markets so you can see who is betting what, their other bets, and so on. The article mentions that other users fingered him for insider trading. That itself opens up an opportunity for profit, by simply following the trades on what he seems to be an insider on. It'd be like if you could see in real time what Nancy Pelosi was investing it - shadow her trades and make big bucks with the soon to be announced market shifting government deal/regulation/etc.
The markets also open up the door for hedging, arbitration and other sorts of opportunities where you don't necessarily even care what the result is.
Right, and that is not some grand secret. Every person taking a side on the bet is aware of that nuance for any trivially gamed market. If you think the size of the market is sufficient to incentivize somebody to do so then that would obviously increase the yes odds.
It's akin to betting on penny stocks in the market where you are also aware that a single person could dramatically shift the market one way or the other if they wanted so you're betting not just on the stock's performance, but also on the meta-market.
I would imagine that in theory, everyone thinks they have the best information at the time, something like:
House: "Odds that X happens? We'll put $1 on both sides to get it started. 50/50."
Someone comes along: "Oh dang, I'm definitely more than 50% confident that X is happening. Let me put $1 in." Now it's 67:33.
Someone else comes along: "Oh I'm more than 67% confident X is happening, let me put $1 in." Now it's 75:25.
And of course, you get people going: "I'm more than 25% confident that X is _not_ happening, let me put $1 in!" And now it's 60:40.
The murky part, I would imagine, comes when the odds and the payout actually act as something that influences the outcome, but in perfect theory-land, if everything goes as planned, this should move the odds to the most informationally-accurate measurement, which should, in theory, benefit observers by making this measurement public.