Posted by m-hodges 3 days ago
Say 70% of the time it resolves to ‘no’, you still don’t make money by blindly choosing ‘no’.
Guess why?
Hint: This strategy is also described with the macabre analogy: picking up pennies in front of a steamroller.
Do you want to pick up pennies in front of a steamroller?
Though I agree it's bad math, even if 70% resolve to no, there's a high variance among all of them, and to know whether it's a good bet or not... you have to do your DD on that particular market. Even if you follow the Kelly criterion, randomly choosing bets will probably tank your bankroll sooner or later.
No, all these variables cancel out.
If you were picking and choosing, yes. But this approach is basically betting no on all the markets.
The textbook explanation of this is the central limit theorem, proving this mathematically is a bit more involved for power-law systems like this but it’s empirically valid.
https://huggingface.co/datasets/SII-WANGZJ/Polymarket_data
"A comprehensive dataset of 1.9 billion trading records from Polymarket, processed into multiple analysis-ready formats. Features cleaned data, unified token perspectives, and user-level transformations — ready for market research, behavioral studies, and quantitative analysis."
Nevertheless, Polymarket is a very interesting marketplace of sentiments and information, and it can be a very strong leading indicator of huge price movements in "real" markets like the NYSE, in part because it directly measures one factor of sentiment, i.e. whatever the prediction is about. Market sentiment determines market prices on very large and deep markets, too.
In the run-up to the election, when Trump was running against Biden, a betting market was a leading predictor of NASDAQ (a very deep, very liquid index of stocks). I wrote up the findings here: https://medium.com/@rviragh/does-the-stock-market-react-posi...
This indicator was the best one anyone has ever shown for NASDAQ for any signal, period. The signal was so strong it trumped all other signals and variances of any kind. Traders trading with just this signal and no other signal of any kind could have made practically an unlimited amount of money as long as the signal was intact. (Basically, until Biden dropped out.)
I myself didn't place any bet due to my role as a political advisor at the time, but the size of the correlation is still the biggest and most surprising one I've ever seen.
The stopped clock is right twice a day, but it reads noon and we're at half past three
I have been making money with a bot off a statistical anomaly in prediction markets lately. There is no way in hell I will open source it or tell you what that anomaly is because I have capacity back-tested it and there are so many players in the market; if all of HN and Github start downloading and use my code it WILL cease to work.
Put another way, your orders are helping move the market and price the market more efficiently; that's the market compensating you for pricing things better. If a thousand people run your strategy, prices will get moved to exactly the point where your strategy stops working. You effectively split that pie with a thousand people.
you wouldn't get it