57 comments

  • SamTinnerholm 3 hours ago

    Nice paper, and thanks for releasing the dataset.

    The "top-1% winners are patient limit-order liquidity providers, not insiders" finding is interesting, and I'd love to see it extended cross-venue.

    I work on tooling that normalizes orderbooks across Polymarket, Kalshi, Limitless, and Smarkets. From that angle, a lot of what looks locally like skilled Polymarket market-making turns out to be cross-venue arbitrage that happens to land on Polymarket. The same underlying question routinely trades 3-8% apart across venues for hours at meaningful depth, and a fast multi-venue stack rests limits on the lagging book at the exact moments the leading book moves. Locally that's indistinguishable from disciplined liquidity provision; cross-venue it's closer to FX triangular arb on the consensus price.

    If your timestamps are fine-grained enough, a clean follow-up: for the top 1% of Polymarket profit-takers, what fraction of fills land within N seconds of a same-question move on Kalshi or Limitless? If it's materially above baseline, some of "skill" resolves into "cross-venue infrastructure" — which is also a more durable edge than within-venue alpha, so it could partly explain the weak monthly persistence you observe (the cross-venue gap closes when too many players run the same stack).

    This might also be consistent with your insider-trading conclusion rather than against it: an insider on a real-world event has every reason to hit the lowest-friction venue with aggressive market orders (Polymarket: permissionless wallets, no KYC, no withdrawal limits). That's a fundamentally different profile from the patient limit-posting strategy your top bucket runs, so the two populations cleanly separate in the data even if both are present.

    • vcf 2 hours ago

      We have a grad student working on matching markets across venues. Not a trivial task at scale, but we hope to look at that eventually.

    • locallost 2 hours ago

      I don't think that's surprising because the alternative would be that some people are able to predict the future. Whatever strategy one might figure out that works is long term destined to fail, as other people start using them. The only real way to make money there is by providing liquidity since it's a zero sum game. For the stock market this is not true because it's not zero sum, it grows over time.

      • tsimionescu 5 minutes ago

        There are some bets on prediction markets where the future is either already known or in the control of people who may be participating in the market. For example, when people bet on how long the next presidential briefing will be, it doesn't take a prophet to predict this, anyone who organizes said briefing can control it (at least with a very high probability).

        So, the question becomes "what is the preponderence of such bets" and "how many people with control or knowledge of bet outcomes actually participate in the market" - not "can some people see the future of any bet better than others".

      • cortesoft an hour ago

        There is alternative to being ā€œable to predict the futureā€, which is ā€œI already know the futureā€ or ā€œI can change the futureā€

        • mathgradthrow 33 minutes ago

          Someone flips a coin and looks at it, what orders are you willing to put in?

          The potential for insiders should be represented by a complete loss of liquidity.

          • tsimionescu 4 minutes ago

            And yet, many people bet on things like the duration or contents of press conferences, of pre-taped shows, etc.

      • Retr0id 2 hours ago

        "predicting the future" and "correct analysis of all available information" often aren't all that different.

        • glitchc an hour ago

          A sufficiently large market is indistinguishable from Brownian motion.

        • AnimalMuppet an hour ago

          From Schlock Mercenary (quoted from memory, may be inexact):

          "You cannot see the future. All we are given is the present."

          "Of course. But if you look closely at the present, you can find loose bits of the future just laying around."

        • dheera an hour ago

          Not really. Not all players in prediction markets are rational players. A good chunk of it are there for entertainment, and analyze things incorrectly; you can take the other side of those trades, and you won't need to predict the future.

          • Retr0id 8 minutes ago

            Deciding that someone else's prediction is wrong is a prediction in and of itself.

            • dheera 3 minutes ago

              You can interpret it that way, but if they're using emotions and you are using data, you have a significant edge over them.

      • vcf 2 hours ago

        Yes, but the alternative (that some people are very good at forecasting) is also plausible. It's also useful to have a good prediction model and timely data sources when providing liquidity. We also find that some of the "biggest losers" also provide liquidity; they just aren't as good at it.

      • dheera an hour ago

        The stock market is arguably zero sum as well, just that directionally betting on the US has generally worked during the golden years of the US economy.

        The stock markets of the world aren't a money printer.

        • cluckindan 3 minutes ago

          They can be in cases where investment lenders don’t have 100% capital requirements, but that’s generally no different from other banks.

    • postflopclarity 2 hours ago

      this comment was clearly written by AI. please don't do that.

      • Retr0id an hour ago

        Not sure why you were downvoted/flagged, because you're right. It is also quite an insightful comment worthy of discussion so I'm a little conflicted.

        • pjc50 an hour ago

          It looks completely fine and plausible to me. Which is worrying.

        • skybrian an hour ago

          I don’t see why it’s AI, but even if it is, it’s better than most human comments so the complaint should be downvoted.

          • Retr0id an hour ago

            Take a look at the user's history, it's more obvious in context. It has a lot of claude-specific tells which are noticeable if you've spent time working with claude. AI-generated comments are against the HN guidelines https://news.ycombinator.com/newsguidelines.html#generated

            • nh23423fefe an hour ago

              phrenology

              • postflopclarity 42 minutes ago

                if you're not able to tell that OP's comment was AI slop, then you probably don't have much insight to contribute to the conversation either.

            • skybrian an hour ago

              Maybe the guidelines should be changed? Something about: don’t complain about comments just because they’re AI.

              • postflopclarity 43 minutes ago

                I'm not complaining "just" because it's AI.

                I'm complaining because it's AI, and also slop.

                > resolves into "cross-venue infrastructure" — which is also a more durable edge than within-venue alpha

                anybody who actually trades knows that on these markets, "cross venue infrastructure" (aka vibe coding some exchange api integrations) is much less important / durable than actual alpha.

                • Retr0id 20 minutes ago

                  Slop aside, do you think it's reasonable to assume a decent fraction of those making consistent profits are arbitrage bots?

                • skybrian 16 minutes ago

                  That sounds plausible. Not a trader so I wouldn't know. Saying at least a little about what's actually wrong with it seems more useful than just saying it's slop, which gives me very little info over just a downvote.

          • postflopclarity 41 minutes ago

            it's only "better than human comments" if you have no idea what profitable trading looks like. it's a very-very thin mildly convincing veneer over what is fundamentally slop.

    • empath75 2 hours ago

      There's probably also some hedging going on across accounts that look like directional bets.

  • vcf 4 hours ago

    We study trading gains and losses on Polymarket, the largest prediction market. Using 588 million trades ($67 billion in volume), we show that the gains are highly concentrated: the top 1% of users capture 76.5% of profits. Successful traders provide liquidity using limit orders that resolve favorably relative to realized outcomes while unsuccessful traders take liquidity using market orders. Monthly performance is weakly persistent, however, this may represent sample selection rather than skill. A detailed analysis of the trading behavior of the most successful accounts suggests that "insider'' trading is unlikely to explain the performance of the largest winners.

    Full dataset available at https://huggingface.co/datasets/vgregoire/polymarket-users

    • wutwutwat 2 hours ago

      insider trading on events probably wouldn't show any trends, right? These are point in time events (they call them markets), but they are finite and short lived. An insider would be a one and done thing, so it would be pretty hard to spot them or trend any sort of month over month insider scheming imo.

      Also...

      > We study trading gains and losses on Polymarket, the largest prediction market

      This is not a natural thing to say and I fucking hate that it's impossible to know anymore if I'm wasting time replying to an AI/bot or not

      • vcf 2 hours ago

        Not meant to sound like AI, but most academic journals limit abstracts to 100 words, so they rarely feel natural...

        I agree: insiders are hard to study because they are finite and short-lived. We're pretty confident there are insiders out there trading on Polymarket; however, our conclusion is that they don't account for a significant fraction of the total trading gains on the platform.

      • philipwhiuk 2 hours ago

        I agree - you're not going to be an insider on a significant proportion of trades and it would be stupid to use the same account for more than a couple.

        Insiders are going to be earning large amounts in single trades, either by betting a lot when it's odds-on or a small amount when it's out the odds (for a large return).

        I think it's just bad tense, which I think makes it not AI amusingly.

  • perlgeek 2 hours ago

    > the top 1% of users capture 76.5% of profits

    This seems to be similar to OnlyFans, and the economy at large...

    • vcf 2 hours ago

      Yes, power laws are everywhere. The exact shape of each distribution varies, however, and little is known empirically about the distribution of trading profits in financial markets.

      • amelius an hour ago

        Yeah if you look at the Boltzmann Wealth Model, where every actor gives away 1 dollar to a random person, and you repeat this, then if you start with an equal wealth distribution, you end up with an exponential wealth distribution. That shows how strong exponential curves are :) A few "lucky" individuals become very wealthy, while the vast majority of people end up with very little or nothing.

        The effect is so strong that I'm starting to wonder if we should have laws against power laws, like we have in engineering when we try to make things stable.

        • bee_rider 11 minutes ago

          Sigmoid wealth tax maybe?

          • trgn 3 minutes ago

            that's what progressive taxation is

        • Balgair 17 minutes ago

          I mean, do we want the economy to be stable?

          Not in a 'oh the rich don't so they control the media and so we don't' sorta way. But like in a 'lets educate people on the pluses and minuses, debate a while, and then come to an informed conclusion' sorta way.

          Like, deep down, does the average person actually want a stable economy? Because it seems to me that there is an even split historically between the folks that want stability and a little patch of land and weekly rhythms, and the folks that just want to drunkenly burn couches in the street every full moon, or some such thing.

          Not to be glib here at all. I like, would actually like to know the answer. Sorry if this comes off the cuff seeming.

    • fantasizr 2 hours ago

      these apps should load with this pie chart showing your likelihood of ever making a profit based on what they know about you. "YOU WILL LOSE MONEY ON THIS APP". Like the cigarette packs.

      • solarkraft an hour ago

        This is (possibly what you’re thinking of) a requirement in the EU for CFD trading providers. Providers have to (somewhat prominently) state in all of their ads what percentage of traders loses money using the product.

        • fantasizr an hour ago

          Interesting, would love to see that applied here. Every third ad is about how I can make money on the weather.

  • goncalo-r 3 hours ago

    What's the baseline here - in a world where every person is betting randomly X times a month, what would the distribution look like? There'd still be a small percentage that wins most of it, right?

    • vcf 2 hours ago

      We don't know the exact benchmark, but your insight is correct. We provide a simulation similar to what you have in mind towards the end of the paper, but you can generate almost any distribution you want by fine-tuning a simulation...

    • Terr_ an hour ago

      To relate it to a more-general economic article that has stuck with me for a while:

      > If you simulate this economy, a variant of the yard sale model, you will get a remarkable result: after a large number of transactions, one agent ends up as an ā€œoligarchā€ holding practically all the wealth of the economy, and the other 999 end up with virtually nothing.

      https://www.scientificamerican.com/article/is-inequality-ine...

  • dwa3592 2 hours ago

    Wait- why isn't there any conflict of interest statement provided in this paper?

    • vcf 2 hours ago

      Because it's not required and not common practice in our field at this stage. But none of us (I'm one of the authors) is affiliated with or has a financial interest in any prediction market platform.

      • HWR_14 2 hours ago

        Isn't it common practice and required to disclose a conflict of interest? Just not to explicitly say there are none.

        • vcf 2 hours ago

          Yes, when you submit for publication. In our field, you rarely see one for pre-prints, unless you have one to disclose.

      • dwa3592 2 hours ago

        Thanks for the clarification. Given the scrutiny on these platforms, this is timely done. Thanks.

  • emsign an hour ago

    In terms of damage to society it's irrelevant who the winners are within the Polymarket system, it matters how much the insiders playing on Polymarket have an effect to the outside world of politics and economics. If Polymarket gambling increases corruption and destructive effects on society it simply has to be regulated or made illegal.

  • tim-star an hour ago

    the market wins

  • manas96 2 hours ago

    Just curious but how are bets arbritated on these website?

    Meaning who decides if an outcome was yes or no? Answers to things like "Who will win the next Best Picture Oscar?" are fairly obvious and binary.

    Can we make bets whose answers are not binary yes/no?

    What about "Will celebraty X and Y break up?"? Does Polymarket go to X and Y to confirm if they broke up or something :D