You though, are claiming that the market is perfectly priced, or should be, such that this strategy won’t work. It’s pretty hard to balance the odds of an animal seeing their shadow vs the expected strike price of the nasdaq. It’s clear you’re not familiar with betting markets, which is in your best interest most likely, but that’s not how this works.
You’re arguing against yourself… against a point nobody made but you.
>These are obviously false.
The purpose of the Ukrainian military is to exhaust the Russian army's materiel and test out our weapons. "Years-long stalemate with Russia? Yes, please." -the US. Seems like an overwhelmingly common Scott Alexander L.
Since when does country A decide what the purpose of country B's military is?
On smaller scale, this is the (in)famous "fire and motion"[0], which works in business as much as it does in military tactics. Make a move, forcing competitors to respond to it. If you're better at it than them (and lucky), you can choose your moves to make their responses go to your advantage.
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[0] - https://www.joelonsoftware.com/2002/01/06/fire-and-motion/
In any case, the blog is well regarded in these circles.
however, from his follow-up post https://www.astralcodexten.com/p/highlights-from-the-comment...:
> When people insist on the confusing and inappropriately-strong version, I start to suspect that the confusingness is a feature, letting them smuggle in connotations that people would otherwise correctly challenge.
i find this comical because it reads like a slightly-differently-worded POSIWID argument :)
There's a ton of scholarly debate about it, and at least most of the early stuff was pretty earnest. But rather than the debate becoming more refined and nuanced over time it seems to have bifurcated along partisan (or partisan adjacent) lines like everything else, similar to the Keynesian/Misesian divide.
The Misesian folks are a lost cause, IMHO. They're hardcore rationalists, self-indulging in circular moral arguments from assumptions that don't apply in the real world.
There are actually two theories on insider knowledge. One states that allowing insider trading is beneficial, as it allows prices to better match the underlying reality, the other states that this discourages non-insider trading, which actually makes the prices worse. Stock markets lean heavily towards the second theory, while prediction markets seem to be leaning towards the first.
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[0] - Or external knowledge, but actual knowledge - thinking of hedge funds stalking CEOs as they fly in private jets, or counting cars in parking lots from satellite photos, to get some probability estimates on factors actually relevant to the performance of a business and possible future events.
Obviously it has come a long way from that, and the markets have become more like gambling. You could probably allow insider trading at this point and the system would continue just fine.
The stock market would not be noticeably less liquid if people had to hold stocks for 24 hours, but volume would drop like a rock.
This theory is fundamentally not credible, the other side of any trade you make on the stock market is essentially always going to be vastly more sophisticated than you. Insider trading makes zero difference to the end-user.
The credible argument against insider trading is that it's a form of theft. You are making trades based on information which does not belong to you, and which you have an obvious duty to protect. You are essentially stealing from the people you work for.
Prediction markets are doing a bit of that. Some won't take bets on an assassination.
If they get assassinated, those markets will resolve to yes. At least the rules don't specifically exclude that.
The original theoretical purpose was to incentivize the creation of new knowledge, not reward insider knowledge that already exists. For example, to fund research that helps answer some unanswered question.
Today, the purpose is obviously gambling. We can see that clearly from the marketing.
Communicating insider knowledge is how the brokers legally/morally justify that business model.
I'm sure in the near future, policy decisions or war strategies will be decided by prediction markets' odds, if they are not already being used.
News sources are motivated to get clicks, to appeal to certain audiences, and to retain tribal customers. None of these create incentives for truth. You can seek out smart, well-informed and principled journalists who will prioritize truth-seeking over money-making. There are some. But the fact remains you are relying on character to override incentives. With prediction markets, incentives and truth are naturally aligned. This makes them a powerful and valuable resource imo, even if there is a lot of scumminess that comes along for the ride. The insiders, more than anyone, are contributing to the truth signal.
See the loop?
First, you have inside traders. Then, among legitimate bettors, you have smart people using multiple data sources (not just the "news") and doing sophisticated analysis that most journalists cannot do, and are not motivated to do -- again, because their incentives are different.
You can do research to know the US would strike, there's no other point in moving multiple carriers over to somewhere. But exactly WHEN is not researchable. This applies to most other bets. So lets stop pretending there's anything more than 2 cohorts, insiders and degenerate gamblers.
I've been doing it profitably myself for almost 10 years now. I have zero special inside knowledge, and no access to any other non-public information.
> Will the US strike Iran by X date
Last year I did think the market for a strike on Iran was significantly underpriced given the information and conditions within a specific frame of time.
I don't think every smart person can just pop into prediction markets and print money, but I know many smart people who are long-term winners. I also don't try to knock people as degenerate when they have genuine talent.
But also motivated to bend the truth to their bet as the journalist in Israel found.
So the feedback from prediction market turns around, so you can essentially buy events if you put enough money in.
The question isn't what percentage of bets resolve to no, but whether there is a consistent bias in the prices away from the fair price, which has an expected value of 0, and what direction that bias is in.
I bet the average price for a no bet across these markets is 73 cents.
From their docs, it looks like they charge fees to bet "takers" (as opposed to makers), but exclude the geopolitical and world-events markets where they don't charge fees.
I have to imagine that may be related to some of the blow-back towards prediction markets about profiting on topics like war & their potential for manipulation.
Given it sounds like the bot bets everywhere other than sports, many of those categories would likely have fees in this case.
Or something like that.
Behavioral economics has already answered the question of whether humans are, on average, perfectly rational economic actors. They are not.
To the contrary, there is substantial evidence indicating a meaningful number of humans will mis-estimate the likelihood of uncommon future events.
The alternative would be that there's a bunch of free money sitting there waiting for someone to decide to pick it up, and nobody is, not even you.
Edit: conversely, if the average no costs _more_ than 73 cents, but the 73% of all polymarkets resolve to No, that would imply that an everything-always-happens strategy is profitable (neglecting slippage)
Or just the bid-ask spread; price no at 73.25 and yes at 27.5 and you have a profitable but theoretical mid-market price.
The whole premise of gambling is that they don't
> [...] if prices perfectly reflected available information, there is no profit to gathering information, in which case there would be little reason to trade and markets would eventually collapse.[2]
That's a stupid way to formulate this. Markets wouldn't "collapse". They would get slightly less efficient until equilibrium is restored to where arbitragers can make enough money to keep prices at that level of efficiency.
Meanwhile Two Sigma is hiring alpha quants to be AI research scientists at $250k starting salary + bonuses.
Even if we're just talking about the HFT/sell-side, there clearly exist various anomalous inefficiencies that can be exploited.
Fama's guy doesn't agree either [1]
https://www.ft.com/content/813b3d76-6ef1-427d-a2e0-76540f58a...
You don't believe in the existence of residual return orthogonal to priced cross sectional risk factors (alpha)?
E.g. Trends, momentum, volatility clustering, etc. many easily demonstrable inefficiencies. VPIN and order flow toxicity are highly predictive features. Most HFT MM especially in crypto involves hybrid alpha also
* https://www.kaggle.com/competitions/jane-street-real-time-ma...
I would have hoped that by now it was obvious that we are talking about a _specific_ weak form of the EMH that takes friction into account?
What is your whole first paragraph about? Who are you trying to convince? Where's the strawman that claimed that the strongest version of EMH that you can imagine is literally true?
There's no single weak form of EMH that could be accurate or inaccurate: there are many versions of the EMH in various strengths and dimensions (that can be accurate or inaccurate).
To be more specific: Jane Street believes (or acts lie they believe) that markets are at least efficient enough that it takes a lot of effort for them to make money. As a very, very weak form: someone doing chart astrology, eh, I mean technical analysis, on S&P 500 stocks won't beat the market. But even much stronger versions than this are defensible.
The real strong forms that say that all information is preciously reflected in profits is a simplifying assumption you can sometimes make to make your life easier. Just like you sometimes neglect friction in physics. But when you want to decide how long your train needs to emergency brake, you kinda need to take friction into account. Similarly, when trying to make money in the market or trying to understand how others like Jane Street make money, the strongest EMH is not a good guide.
There are 3 accepted forms of EMH. I'm talking about weak form - just price history and nothing else. E.g. formulaic alpha have demonstrable predictive value in modeling.
All that to say you believe trading profits are real. Maybe you just need to learn more about what a buy side alpha quant at two sigma does for a living. Trading models can be robust and exploit real inefficiencies. Weak form EMH is demonstrably false on it's face, as you agree.
Huh, no?
The way you're speaking about trading in terms of technical analysis implies you have retail trading exposure and have no idea what institutional alpha quants do.
This explainer might help you understand: https://youtu.be/RpCzaEn4rnc?t=257
Whether there is enough of a predictable bias there to snag enough low return high probability bets to beat the vig and not shift the markets I have not looked into in any way,but it is a known bias with them.
The real money to be made in prediction markets is being the ones with the actual knowledge which is arguably why they are useful and why for some topics, people find them abhorrent.
If the market isn't resolving soon, the small return might not be worth it.
I wonder what it means exactly. Typical Polymarket looks like this:
X happens before May. [Yes][No]
X happens before June. [Yes][No]
X happens before July. [Yes][No]
...
So even if X ended up happens in December, it's still 12.5% Yes and 87.5% No?
Successful project imo.
The bot has zero risk management and I have a strong disclaimer on the github it is essentially a meme.
73% of all polymarkets do resolve to No though.
There's a good dataset on huggingface if you wanted to do some data science
https://huggingface.co/datasets/SII-WANGZJ/Polymarket_data