This is small potatoes compared to the rain gauge tampering farmers were doing in Colorado. There was a recent conviction for $6.5 million dollars of fraud against the federal crop insurance program!
> There are no indications so far that the successful punters have had to return their winnings. However, the data source for Paris’s hottest temperature has since moved to a sensor at the smaller Paris-Le Bourget airport.
Here's the negative externality that no one will care about. There's no reason gamblers won't repeat this stunt, until us poor schmucks who just want an accurate temperature reading have to build a fortified compound in order to do so.
This is an existing problem with physical world sensing. Some data models are already heavily polluted by people manipulating observations for various purposes. Most people who rely on those measurements are just collateral damage. Prediction markets provide yet another incentive. It is far more difficult to reliably get at "ground truth" than I think people imagine.
Unlike computing systems, the physical world is a shared mutable environment. It is effectively impossible to lock people out so that you can get a reliable, clean measurement even when people are not intentionally sabotaging the data model.
There are ways to robustly clean this up analytically but it is largely beyond the capabilities of current tech stacks.
Manipulation of datasets is something that already existed, yes. But what betting markets do is create more incentives to screw with the real world.
You're right that this isn't a technical problem, it's a social one. This is why most sports leagues simply banned betting... until recently, now that gambling companies have bought their way in. The players always end up manipulating games.
> There are ways to robustly clean this up analytically but it is largely beyond the capabilities of current tech stacks.
Can you expand on that? Even just conceptually that sounds really hard, how would you know whether you're measuring genuine (unexpected) changes in the environment rather than the result of (possibly sophisticated and coordinated) deliberate manipulation?
Re externalities, don't they use the temperature to calculate the length of the takeoff roll and other stuff about the flight, fuel load, etc? Maybe they use the plane's own temperature sensors for that though.
Usually the TOS of these betting markets prohibits tampering. IIRC, someone bet on a streaker at the super bowl, did the streaking themselves, made 6-figures on the bet, bragged about it publicly, and the market negated the bet and recovered the money.
> IRC, the TOS of these betting markets prohibits tampering.
Good luck proving it.
> IIRC, someone bet on a streaker at the super bowl, did the streaking themselves, made 6-figures on the bet, bragged about it publicly, and the market negated the bet and recovered the money.
Yeah, exactly. Far easier to prove and to even get the idea to investigate that person in the first place.
The markets make their own TOS and define the burden of proof needed to overturn a bet. They don't want tampering to risk their cash cow, so I'd imagine they are going to be proactive.
I'll tell you another thing that will risk their cash cow - a reputation for not paying out when gamblers win big, because of vague and specious accusations of fraud (which the gambler denies)
>There's no reason gamblers won't repeat this stunt, until us poor schmucks who just want an accurate temperature reading have to build a fortified compound in order to do so.
The issue here is you'd need a lot more land because any asphalt near a temp sensor is going to give you bad data.
So the "negative" externality is that the data you value has been forced to now be higher quality/reliable? From your perspective, isn't the result a positive?
I'm guessing the point was that the data was already high quality and reliable until these legalized prediction markets introduced perverse incentives to manipulate it.
No the negative externality here is that we've derived a value directly to this data, thereby negatively incentivizing this poor behavior. To further elucidate, it effectively introduces a cat-and-mouse game for the people who actually care about the data itself, they now have to worry about nonsensical third party behavior.
Only if you refuse to acknowledge the deleterious effects on society from ruining any notion of trust.
Being held hostage by bad actors until you fortify your defenses seems to be a very unnecessary technical solution to an easily predicted social one.
Normalizing this only means the subterfuge becomes more subtle, not that you remove it entirely. But you preserve the incentives by not changing this system. So you're spending a lot of resources wastefully when you could just... not.
lol, the OP is such a classic HN take. "Why doesn't society simply absorb a negative externality created by gambling and add high cost redundancy layers that are otherwise useless" - Not every problem is technical.
Because that wasn't what caused the problem? The reason it didn't work was some asshole intentionally tampered with the equipment, not because of where it was.
I am a bit surprised by that for a scientific application where you want high accuracy reading. Temperature sensors has a error margin, and I think they can also drift a bit.
In a bit of expensive equipment I own it happens to have 4 temperature and pressure sensors, located in two different locations on the unit. All of them generally disagree with each other on the exact temperature by around 0.1 C, which is fine for my use of it.
Why didn't you put two locks on your door? Clearly you deserved to get burgled if you only used one.
Building Byzantine fault tolerance into absolutely everything is expensive, and makes everything we do and buy more expensive. It would be better and cheaper to rely on social trust, if that's possible-- and it was possible before these gambling sites. Prediction markets are burning social trust as fuel to make profit, they should be heavily taxed, the way polluters are taxed, as destroyers of the commons.
Prediction markets and all the market manipulation are the symptom, not the cause. Our society used to have real consequences for breaching public trust, but with our mere decades old "money is speech" legal system, there have not been any consequences for moneyed interest in quite a while. And as long as there are no consequences, they keep trying more and more egregious violations of public trust to establish where the new red line (if any) actually are.
Money is speech - but speech isn't speech. What's the latest thing a US citizen said in the US that got them arrested? They said in a private WhatsApp group that Benjamin Netanyahu should come and bomb their school to get them out of an exam. Benjamin Netanyahu was not in the group chat, but they got arrested anyway.
>Why didn't you put two locks on your door? Clearly you deserved to get burgled if you only used one.
I can reasonably test that the bolt is in a locked position every time I close the door and turn handle on the lock. But a single remote sensor could have malfunctioned or simply be out of calibration a few degrees.
If the actual temperature at the airport is important to any set of users enough so that the difference between it being 18 or 22 deg C is relevant, one should expect that there be at least 3 sensors (much like clocks) and assuming variances between the 3 sensors are within tolerance an average of the 3 temperatures is taken.
I mean, there are plenty of negative externalities that this type of gambling brings that are much worse, but at least in this case it does appear that authorities are investigating. At the very least I would expect some law to be broken if interfering with official weather data collection at an active airport.
> A few years years ago, there was no conceivable profit motive for interfering with weather sensors on public property. Now there is one.
Can this really be said with a straight face?
Suppose you're an oil company, or a trader with a large position, and "hottest year on record ten years in a row" is bad PR that will make bills you don't like more likely to get passed. Or for that matter a company selling carbon capture stuff who wants to make sure it goes the other way. How about tobacco companies?
This has been a huge problem for as long as public data has been used to make decisions affecting profits.
> Your argument is that people had no existing profit motive to use dirty tricks to influence scientific results/data?
No, that's way too broad. I don't believe that, and I didn't write that.
Oil companies indeed had enormous incentives to obscure and confuse the scientific record of climate change. But hiring thousands of Taskrabbits to go around the world blowing hot and/or cold air on weather sensors would not have helped them: some of them would have been caught, and it would've been exposed as a hamfisted and shambolic scandal.
Oil companies had to do larger-scale, longer-term stuff like funding think tanks, lobbying politicians, and writing op-eds.
Now, because of prediction markets, the "attack surface" for interfering with scientific data collection is much larger and more fine-grained. The incentives for big oil companies probably haven't changed much… but now any random amoral idiot or degenerate gambler has an incentive to go find unguarded weather stations or water quality monitors, etc, and mess with them.
> A few years years ago, there was no conceivable profit motive for interfering with weather sensors on public property.
I have bad news for you. The manipulation of weather sensors for profit has a history that long pre-dates prediction markets. You just weren't paying attention until now.
The total open interest of all major prediction markets is barely over a billion dollars. (1) That's the total amount of money currently wagered on ALL contracts across all platforms.
There are roughly 2,500 individual companies listed in the US alone with a market cap that exceeds 1 billion dollars. Tesla's market cap is 1.4 trillion - about 1,000 times the size of all prediction markets put together.
In other words, to the extent this incentive is of societal concern, it is not because of prediction markets - that is the tail wagging the dog.
Edit: to be clear I think these markets are a scourge as they currently operate, but not for this reason.
This hypothetical situation had existed since the dawn of capital markets, or at least since the dawn of short selling. I don’t think we’ve ever seen anyone get assassinated to make a short bet pay off though.
And there is an obvious reason for this. Murder is very illegal. You therefore don't need short selling to be illegal because if someone sells short without killing anyone then that's fine, and if they do assassinate someone then you don't need to be able to charge them with short selling because you can charge them with murder.
Notice also that the murder is the thing you don't want happening in your jurisdiction, so that's the thing you have to prohibit anyway, because even if you ban short selling or prediction markets in your jurisdiction, having them in any other jurisdiction in the world would allow anyone to just place their bet there and you're right back to needing to deter that by punishing the murder rather than the bet.
Assassination markets where being discussed back in the 1990s.[1] I think it's been pretty clear for a while that "prediction" markets were going to arrive at the same place.
> Later, a single user would make over $550,000 after betting that Ayatollah Ali Khamenei would topple, just moments before his assassination by Israeli forces.
It hasn't happened in this case. Your example has causality reversed. Khamenei wasn't killed because there was a prediction market about the political leadership of Iran.
I don't think you even need to attack anybody to do this. Just have an AI media package ready for the top-N CEOs, and wait for any incident involving their name and "injured", "hospital", "attacked", etc. Then short the stock, go to social media and show the CEO being transported in an ambulance, or a gurney with a sheet over it, "X still missing", whatever.
Probably automatable, and simply counting on automated systems and panic selling. Might be possible just with the AI package these days (not even requiring a traditional media article).
That has proven not to be the case with sports betting. Otherwise every major league pitcher would be needing armed guards to stop all the people with pipes trying to disable them. Seems there is at least some morality to not harm people but no issue in harming temperature sensors so where is the split line? Some really annoying ones like trains being on time can impact thousands yet i could see someone stepping out on tracks to make a train break to delay it to win a bet
> That has proven not to be the case with sports betting. Otherwise every major league pitcher would be needing armed guards to stop all the people with pipes trying to disable them.
This is a ridiculously over-broad claim.
First of all, prediction markets shift incentives in a pernicious way; they don't magically erase or override all pre-existing incentive structures.
And secondly, professional athletes of all stripes appear to be receiving a lot more threats of violence from gamblers (including "prediction market traders") than they were a few years ago.
In fact sports bodies are complaining of exactly that being the case, even in (especially in) much more obscure leagues than Major League Baseball (whose pitchers are compensated enough to cover their personal security):
When the vice industry kept gamblers mainly confined to their own community, it was ugly enough (see the “people with pipes” debt collection trope you refer to). I don’t see any good in letting those behaviors and motivations slop out onto the wider world uninvited.
“Forecasters incentivized by greed produce more accurate predictions in the aggregate” seems like an awfully skimpy fig leaf. If there’s really economically-relevant marginal value in tightening the error bars on every single forecast of every single indicator, in every measurable corner of human enterprise—then the betting parlors should be able to measure and demonstrate that; and the people who produce and rely on those indicators should be willing to pay something to capture the advantage, right?
I’d draw the morality line at, don’t bring gambling to anywhere that didn’t ask for it. If I—as the entity who incurs the cost to produce an indicator—want to hire the prediction market to run bets on it at arms’ length from me, fine. If not, no.
> Just wait until they start killing people to win bets.
Quite likely it has already happened.
There's been an enormous amount of betting on various military strikes by the Trump administration, much of which looks like insider trading.
Almost certainly there have been insiders with money on the line who were financially motivated to launch lethal attacks, which they might have otherwise paused or delayed.
Sure, but then what if in the several hours before the decision is executed, new information comes in?
Your decision maker is now going to make decisions differently than they would if they hadn’t made the bet, due to the financial incentive. It hopefully won’t be blatant, but they’re going to be more committed to the original decision.
I'm pointing out that the version where the market causes the decision is the much less effective way to do things. So I don't think it's so certain to have happened.
When the decision comes first it's still a problem but it's a very different problem.
I should make this explicit, I guess: If you make the decisions before betting, you don't really care what the market says beforehand, you'll make plenty of money either way.
(Having seen your edited and clarified comment, I think we basically agree.)
> the version where the market influences the decision is the much less effective way to do things.
Okay, so two possible scenarios: "market influences decision" and "decision influences market."
1. Polymarket offers a contract called something like: "Will the US launch any lethal boat strikes in the Caribbean on April 30, 2026?" A commander of a drone unit for the US military bets $500 on "yes". At 11:51pm on April 30, he's trying to decide whether or not to issue an order to fire on a boat, or to wait 15 minutes for better visual identification of the target. As a result of his bet on Polymarket, he's strongly incentivized to issue the order right now.
2. It's 11:51pm on April 30. A commander of a drone unit for the US military is reviewing images of a potential target boat. He idly opens a browser tab to Polymarket. Lo and behold, he sees that the odds of "Will the US launch any lethal boat strikes in the Caribbean on April 30, 2026?" are at only 0.3%. He's strongly incentivized to issue an order to strike right now and to quickly buy that Polymarket contract before news of the strike breaks.
Does it matter which of these two scenarios might actually be taking place? I don't think so.
The payout is much higher if you make an unlikely thing happen. "Unlikely things" in politics & warfare are probably highly correlated with irrational or irresponsible decisions.
Betting against what is widely considered as “expected”, “reasonable” is such a major source of profit when one can influence the income. Whether it’s a temperature sensor one can breathe on or movement of troops one can control or influence[0], the idea is the same—except in one of the above you can add “death and suffering” in addition to some unfortunate gamblers losing their money.
A depressing thought: it will only tip in favor of common good when the probability of something that we today consider “normal” becomes so small that betting on that finally becomes profitable to insiders with influence. Imagine that world…
[0] No, I’m not going to change my writing style because it is considered a “tell” of LLM use.
I don't mean to detract from your point, but regarding your footnote, you seemingly have. Unless it is in your writing style to make direct asides about how one may infer your message was procured.
I've been quite successful trading weather prediction markets.
The prediction markets were never about predicting outcomes. If that's the level you are playing on, you're playing at the lowest possible level, and probably won't win.
The markets are now about properly modelling other peoples' manipulation of prediction. That's how Wall Street works as well. Companies can beat earnings and their stocks crash immediately after. It makes zero sense if you just model companies. It makes full sense if you stochastically model how an ensemble of humans behave under incentives and human-written bots behave under human-written policies.
"Hairdryer sometimes get pointed at the weather sensor" and "Government sometimes fudges jobs/CPI data" are more or less the same thing. Build it into your model. That's the level you need to play on to profit in these markets. It's not that different from how a chess engine works.
I don’t understand why these bets are allowed at all. Can one just make an account there and bet in anything?
The whole “prediction market” charade is increasingly proving to lend itself to abuse. I hope regulations catch up with it soon, otherwise more shenanigans will follow.
The problem is that the genie is out of the bottle, even if you try to regulate it away it pops up in offshore jurisdictions and uses crypto. The ease with which polymarket can be manipulated is infinite because there are so many different random things you can bet on. It's a sign of our times and I don't think there is much that can be done about it by anyone.
This vastly increases the barrier to entry for the normal person though. Is your position that just because laws don't work 100% of the time we shouldn't bother with them?
But wow what a useless way of conversing that is. They asked because it's unclear what you're implying. So could you please clarify if you think regulation would be useful? Or should be done despite being futile? Or shouldn't be done? I can only think of those three answers, is there another?
I think smart policy would be a good start. I just made a comment on the sign of our times. I could have worded my one line reply better. I do think it will be difficult to regulate as I don't see a political appetite to do so. Maybe some countries will get it right.
> It's a sign of our times and I don't think there is much that can be done about it by anyone.
Isn't cryptocurrency (for the most part) very traceable? If you make it too hard and risky for most people to participate in, you'll limit the negative effects. You could probably quite effectively discourage it by sanctioning any transactions with one of these markets, you've got some opportunity because at some point the cryptocurrency needs to be converted to/from cash.
Of course, you'd have to dedicate some investigative and enforcement resources to the effort.
If to bet on a prediction market you have to both use a VPN and launder your money like you're a drug dealer, and I don't think many people would do it.
> Isn't cryptocurrency (for the most part) very traceable
Mostly no. If you're connected it to a banking account, or other KYC platform, maybe, but the folks capable of doing that are part of the same administration supposedly doing the manipulation, so they would not investigate themselves.
Indeed, they are actually fighting against those trying to regulate it [0]
Indeed, the president's son works for Polymarket, and has invested in it [1]
>> Isn't cryptocurrency (for the most part) very traceable
> Mostly no. If you're connected it to a banking account, or other KYC platform, maybe,
But if you're (say) and American betting on it, the money almost certainly flows through one of those entities. And if you're using bitcoin the ledger is totally public, so you could track it from Coinbase (KYC) to whatever wallet the prediction market is using to accept payment (or vice versa).
> Indeed, they are actually fighting against those trying to regulate it [0]
Choosing to "do something about it" or not is a different question than can something be done at all. I was addressing the latter.
Bans from the AppStores will go a long way to removing this behavior.
Sure a few die hards will always find a way to gamble, that does not mean we should not have regulations for the majority.
We seem to be seeing the repetition of every stock/securities fraud that led to the creation of the SEC. But we're seeing people who refuse to let any reasonable regulation to happen.
Anything on the site? Yes. Anything at all? No - Polymarket themselves make the markets (and I think they have some partners that can make markets as well, but point is some random user cannot make a market).
Yep, you can bet on anything. Mike Selig is in charge of regulating it, and he's pretty zealous about suing any state regulators trying to exercise their right to regulate gambling. I think the days of the wild west are clearly numbered, but one guy with a burning passion and a big agenda (and the backing of Don Jr) can get a lot done in the meantime
As Ukrainian I find bets if some city would be captured - peak degeneracy. People are being sent to die or protecting their homes should not be someone bet.
There are communities larger than you'd expect around just about every topic imaginable. I'm certain there are temperature enthusiast groups, especially given its adjacency to climate stuff. It's probably going to be people mostly betting on something they have better than average knowledge of. I'd be interesting to compare the 'normal' majority temperature predictions from polymarket to local weather station predictions. I'm betting polymarket wins, by a wide margin.
For instance chess wagers on polymarket are super interesting because it's far more informative than a chess engine, even though engines are much stronger than any human. The nuance is that engines don't appreciate human factors like how easy/hard a position is to play. And so an engine might just say 'dead draw', whereas a strong human can say 'nah, white has very good winning chances here' - and the polymarket wagers end up reflecting that. And so there it's mostly strong players making money from people who think turning on their engine and betting based on what it says is something nobody else must have thought of.
People bet on anything and everything, and the less controllable the better, afaict. "I'll bet you $5 that snail will eat the cucumber before the broccoli" - > "fuck yes, make it $20" is 100% a thing I could see happening. Weather is significantly easier to do every day though, unless you know a snail farmer with a twitch stream (if so, hook me up!).
It sounds like the other side of the bet was the actual winning bet when compared to Truth. Maybe they have great climate models and actually make a bet that they have an edge on. Maybe they have a gambling problem. Either way, they are the victims here.
You're wrong. The big prediction markets (Polymarket, Kalshi) employ in-house market makers and contractors. They provide liquidity for less-active contracts. They generally are not profitable.
Why do you think it’s a nonstarter when so many of these new platforms do commit fraud all the time and get away with it? It’s only a problem if they get caught, and then only if people actually pay attention enough to care
So? There’s no game with payout odds in your favor.
Lotto (at least where I live) also shows the odds, which are always ridiculously low. Still, people play, because the human brain isn’t built to understand odds. It’s essentially worthless as a metric.
> While it is unclear how the temperature might have been manipulated, one possibility shared on weather forums was that a battery-powered hairdryer could have been used
Man I hate headline writers…
We’re I contracted to (legally and ethically) red team a temperature station, a “battery powered hair dryer” would be pretty low on my list of techniques for a number of reasons. First attempts would involve mirrors - parabolic or otherwise- to heat the device from a distance without potentially affecting wind speed / direction sensors.
> On April 15, one trader made $21,000 (£15,600) betting that the maximum temperature would not be 18 degrees, data from Polymarket show. A temperature of 18C was seen as a 99.6pc probability before the temperature spiked later in the day.
I believe that these are the specific Polymarket bets in question:
How is it even remotely as destructive as casinos, where the odds are always against you? From a probability perspective Polymarket is much more fair, as you actually have positive expected value if you have an information advantage.
Yup. Gambling is already bad but somewhat contained within the walls of a casino or race track.
When you put money on the line for events that are influencable, things get dark fast.
Seemingly harmless sports betting is rife with stories about mob members going to extreme lengths to change the outcome of a sporting event.
It's not hard to see how bad a bet like "so and so won't show up to event x" can go. These don't have to be bets about killing or injuring people to result in people being killed or injured to win a bet.
I will make this argument in favor of casinos, which is that at least we have coevolved with them. They've been around for centuries. We collectively recognize the dangers. We are not collectively blindsided by them.
Individually, yeah, by all means they can prey on people. But they're on the list of things that have been preying on people for centuries, like alcohol, and all kinds of other things. Ring-fencing casinos has a track record of some success at containing them.
I mean, sure, I'd love to wake up tomorrow and for all of the human race to have advanced to the point that to every last individual we are no longer gambling and that industry vanishes in a puff of smoke. I am as far into the belief that they are immoral as it is practically possible to be. But they are at least a known and knowable risk.
These prediction markets are blindsiding us. We could put up with them for another few decades until we coevolve further with them, or we could just, you know, not. Just end them now. Plus, prediction markets have a certain meta-ness to them that casinos largely lack that will keep them fresh and coevolving their own new ways to predate on us. Casinos have basically reached their final form, prediction markets could take yet more decades to get there and it's possible there isn't a stable endgame with them. Or, again, we could just end them here and now.
I don't understand this logic. If people with information advantage get to cheat and win, then everyone without that advantage gets screwed. I struggle to see how this is even remotely "fair". It's like playing poker, but some players get to see what everyone's cards are.
Even humoring your logic begs the question: Why is monetizing an "information advantage" valuable to society?
Casinos are regulated and have to be much more transparent. In Europe and Australia slot machines are required to have appx min RTP (return-to-player) of 95%. With sportsbetting, bookmakers cannot just make up results. It's a dirty business preying on weak, but it's not hiding that.
Polymarket prediction results can be swayed by whales and differ from reality.
Example: they ruled Tesla unsupervised full selfdriving a real usable feature in ~Feb 2026. It still doesn't exist and won't. This decision is far from being the only such one.
Here's a thought experiment for you: if "fiat currency=bad" and "hard money=good", why did the world collectively switch? Where are all the prosperous societies that held the line?
Wonder how the founders/board/investors of the bad incentives factory would manage their site after a massive crowdfunding campaign bet that they'd all still be alive in 2027.
For a while it wasn’t in the US. They now have a cut-down version. But a lot of people use VPNs to access the less-restricted international version. So to answer your question, a lot of users are using it in a way that’s illegal.
It creates financial incentives for anti-social behavior and the proposed benefits of it being a way to determine truth are dubious and self-serving and would not be worth the societal cost regardless.
At some point, the market for markets will demand better regulation than this. But I find it a little absurd that anyone is still putting their money into these markets with story after story of obvious fraud.
Reminds me of when I made about $40k finding a source that had CO2 data in close to real time when other people were tracking one about 12 hours delayed
John Oliver had a segment on prediction markets this week. It covers insider training and opportunities for blatant manipulation like this, well worth checking out. The example in the Last Week Tonight segment was betting on dildos being thrown on court during a WNBA match. And then travelling to the match to throw the dildo.
Why is the WNBA alarming at all (other than the fact that we shouldn't be throwing dildos on the court at all, of course)?
I'm just not sure why anyone would take a bet against someone who can single handedly make their side win. It would be like someone making a bet that I won't eat a hot dog for lunch tomorrow. Of course I'm going to eat a hot dog for lunch tomorrow. Why is there anything alarming about that? It's just stupid that anyone is taking the other side of that bet.
> While it is unclear how the temperature might have been manipulated, one possibility shared on weather forums was that a battery-powered hairdryer could have been used, according to Le Monde newspaper.
The libertarian argument for prediction markets is really beautiful.
It's just a pity it basically depends on all participants in the prediction market being basically unaware that they are participating in a prediction market, and being oblivious to the incentives to create the outcomes they are predicting by the very act of predicting it with money.
But other than that minor detail, that little minor catastrophic flaw in the foundation, it's a beautiful argument.
I think we can call it as a society. It's a failure. We can go back to banning them, not just for moral reasons, but just pragmatic ones. The theory doesn't work. The supposed benefits don't manifest, and "unanticipated" costs to everyone do. We did the experiment. (Again.) We can close this out now.
And as a result we should gain stronger epistemology. How many cities base their official temperature readings on just a few sensors rather than a widespread network?
Sure you might argue, maybe this was an issue with Polymarket choosing a weak source rather than the gov, but is that really true? If you question measurements like this you quickly get labeled an climate denier.
IMO this is good for the world, temp measurements should be based on thousands of sensors not just one. And if cloud seeding works, all the better for humanity, it's likely a key to terraforming future planets.
You completely missed the issue. Météo-France already has tens of thousands of stations across the country, they're very obviously not basing their entire models off of one sensor in Paris CDG.
The degenerate idiots from Polymarket bet on this particular sensor. There's no law preventing people from betting on single sensors. And we can't make laws preventing people from acting on the world in all the diverse ways that can be exploited to cheat in prediction market.
We should just blanket ban this negative-value industry. We don't want people betting on forest fires and then starting them.
> I wonder when someone who does cloud seeding will place a bet about rain at some unlikely time and place.
Each year, one of my state's legislators introduces a bill to outlaw chemtrails [0]. It never leaves committee. This year, he added the plot of Termination Shock [1] to his bill. This proposed legislation already includes "cloud seeding" as a crime. Penalty of $500k/day and each day is a separate crime.
This is small potatoes compared to the rain gauge tampering farmers were doing in Colorado. There was a recent conviction for $6.5 million dollars of fraud against the federal crop insurance program!
https://www.justice.gov/usao-co/pr/two-southeastern-colorado...
Small, shriveled, drought-stricken, dessicated potatoes.
People have no idea how pervasive this is globally.
> There are no indications so far that the successful punters have had to return their winnings. However, the data source for Paris’s hottest temperature has since moved to a sensor at the smaller Paris-Le Bourget airport.
Here's the negative externality that no one will care about. There's no reason gamblers won't repeat this stunt, until us poor schmucks who just want an accurate temperature reading have to build a fortified compound in order to do so.
This is an existing problem with physical world sensing. Some data models are already heavily polluted by people manipulating observations for various purposes. Most people who rely on those measurements are just collateral damage. Prediction markets provide yet another incentive. It is far more difficult to reliably get at "ground truth" than I think people imagine.
Unlike computing systems, the physical world is a shared mutable environment. It is effectively impossible to lock people out so that you can get a reliable, clean measurement even when people are not intentionally sabotaging the data model.
There are ways to robustly clean this up analytically but it is largely beyond the capabilities of current tech stacks.
Manipulation of datasets is something that already existed, yes. But what betting markets do is create more incentives to screw with the real world.
You're right that this isn't a technical problem, it's a social one. This is why most sports leagues simply banned betting... until recently, now that gambling companies have bought their way in. The players always end up manipulating games.
> There are ways to robustly clean this up analytically but it is largely beyond the capabilities of current tech stacks.
Can you expand on that? Even just conceptually that sounds really hard, how would you know whether you're measuring genuine (unexpected) changes in the environment rather than the result of (possibly sophisticated and coordinated) deliberate manipulation?
"Some data models are already heavily polluted by people manipulating observations for various purposes"
Example of this?
that argument is insane
Re externalities, don't they use the temperature to calculate the length of the takeoff roll and other stuff about the flight, fuel load, etc? Maybe they use the plane's own temperature sensors for that though.
Yes we've got to stop this. Meanwhile dictators are laughing at us while our totally free "thus, awesome" society kills itself.
Usually the TOS of these betting markets prohibits tampering. IIRC, someone bet on a streaker at the super bowl, did the streaking themselves, made 6-figures on the bet, bragged about it publicly, and the market negated the bet and recovered the money.
So if he had paid someone to streak he would have gotten away with it though.
We are only seeing the very dumb here.
> IRC, the TOS of these betting markets prohibits tampering.
Good luck proving it.
> IIRC, someone bet on a streaker at the super bowl, did the streaking themselves, made 6-figures on the bet, bragged about it publicly, and the market negated the bet and recovered the money.
Yeah, exactly. Far easier to prove and to even get the idea to investigate that person in the first place.
The markets make their own TOS and define the burden of proof needed to overturn a bet. They don't want tampering to risk their cash cow, so I'd imagine they are going to be proactive.
I'll tell you another thing that will risk their cash cow - a reputation for not paying out when gamblers win big, because of vague and specious accusations of fraud (which the gambler denies)
They don't want the appearance of tampering. They don't really care about tampering itself because they make their money either way.
So as long as you are subtle about it they won't even investigate, as a public investigation would make it seem like tampering was common.
>There's no reason gamblers won't repeat this stunt, until us poor schmucks who just want an accurate temperature reading have to build a fortified compound in order to do so.
The issue here is you'd need a lot more land because any asphalt near a temp sensor is going to give you bad data.
Thats just not true. Generally you want to place a sensor 5 feet away from any structure. That's not a lot of land
What do you think taxiways are made of? Or parking lots?
> The issue here is you'd need a lot more land because any asphalt near a temp sensor is going to give you bad data.
Ah yes. The way to measure temperature in the city is to move the thermometers outside of the city. Makes perfect sense.
So the "negative" externality is that the data you value has been forced to now be higher quality/reliable? From your perspective, isn't the result a positive?
I'm guessing the point was that the data was already high quality and reliable until these legalized prediction markets introduced perverse incentives to manipulate it.
No the negative externality here is that we've derived a value directly to this data, thereby negatively incentivizing this poor behavior. To further elucidate, it effectively introduces a cat-and-mouse game for the people who actually care about the data itself, they now have to worry about nonsensical third party behavior.
How can you know the data is higher quality?
In my city, the airport has wildly different weather than the city center, and the data I get has no relation to what I experience, for example.
Only if you refuse to acknowledge the deleterious effects on society from ruining any notion of trust.
Being held hostage by bad actors until you fortify your defenses seems to be a very unnecessary technical solution to an easily predicted social one.
Normalizing this only means the subterfuge becomes more subtle, not that you remove it entirely. But you preserve the incentives by not changing this system. So you're spending a lot of resources wastefully when you could just... not.
But why are they only using one sensor?
Because we used to be a high trust society where degenrate gamblers wouldnt mess with scientific equipment to rip each other off
lol, the OP is such a classic HN take. "Why doesn't society simply absorb a negative externality created by gambling and add high cost redundancy layers that are otherwise useless" - Not every problem is technical.
To be more generous, it is the action that can be taken unilaterally.
Trying to eliminate gambling has vexed many an emperor and cleric.
Counterpoint, why are we measuring temperature on what is basically a giant radiator?
Because that wasn't what caused the problem? The reason it didn't work was some asshole intentionally tampered with the equipment, not because of where it was.
Counter-counterpoint, why are people wagering on an airport thermometer measurement?
I am a bit surprised by that for a scientific application where you want high accuracy reading. Temperature sensors has a error margin, and I think they can also drift a bit.
In a bit of expensive equipment I own it happens to have 4 temperature and pressure sensors, located in two different locations on the unit. All of them generally disagree with each other on the exact temperature by around 0.1 C, which is fine for my use of it.
Why didn't you put two locks on your door? Clearly you deserved to get burgled if you only used one.
Building Byzantine fault tolerance into absolutely everything is expensive, and makes everything we do and buy more expensive. It would be better and cheaper to rely on social trust, if that's possible-- and it was possible before these gambling sites. Prediction markets are burning social trust as fuel to make profit, they should be heavily taxed, the way polluters are taxed, as destroyers of the commons.
Prediction markets and all the market manipulation are the symptom, not the cause. Our society used to have real consequences for breaching public trust, but with our mere decades old "money is speech" legal system, there have not been any consequences for moneyed interest in quite a while. And as long as there are no consequences, they keep trying more and more egregious violations of public trust to establish where the new red line (if any) actually are.
Money is speech - but speech isn't speech. What's the latest thing a US citizen said in the US that got them arrested? They said in a private WhatsApp group that Benjamin Netanyahu should come and bomb their school to get them out of an exam. Benjamin Netanyahu was not in the group chat, but they got arrested anyway.
It's not like there aren't literally hundreds of sensors across the city.
>Why didn't you put two locks on your door? Clearly you deserved to get burgled if you only used one.
I can reasonably test that the bolt is in a locked position every time I close the door and turn handle on the lock. But a single remote sensor could have malfunctioned or simply be out of calibration a few degrees.
If the actual temperature at the airport is important to any set of users enough so that the difference between it being 18 or 22 deg C is relevant, one should expect that there be at least 3 sensors (much like clocks) and assuming variances between the 3 sensors are within tolerance an average of the 3 temperatures is taken.
You could just sue, but usually gambling is already illegal in most jurisdictions unless licensed in the location.
Not in the US anymore. Polymarket etc are all de-facto gambling (unless you're insider trading), and the US government isn't doing anything about it.
I mean, there are plenty of negative externalities that this type of gambling brings that are much worse, but at least in this case it does appear that authorities are investigating. At the very least I would expect some law to be broken if interfering with official weather data collection at an active airport.
I agree, but the fact that authorities even have to spend time investigating is a massive negative externality.
A few years years ago, there was no conceivable profit motive for interfering with weather sensors on public property. Now there is one.
This is the definitive argument for me against prediction markets. It creates incentives to do really dumb shit.
Yep. Feels like we see new depressingly creative examples of this every few days.
> A few years years ago, there was no conceivable profit motive for interfering with weather sensors on public property. Now there is one.
Can this really be said with a straight face?
Suppose you're an oil company, or a trader with a large position, and "hottest year on record ten years in a row" is bad PR that will make bills you don't like more likely to get passed. Or for that matter a company selling carbon capture stuff who wants to make sure it goes the other way. How about tobacco companies?
This has been a huge problem for as long as public data has been used to make decisions affecting profits.
> Your argument is that people had no existing profit motive to use dirty tricks to influence scientific results/data?
No, that's way too broad. I don't believe that, and I didn't write that.
Oil companies indeed had enormous incentives to obscure and confuse the scientific record of climate change. But hiring thousands of Taskrabbits to go around the world blowing hot and/or cold air on weather sensors would not have helped them: some of them would have been caught, and it would've been exposed as a hamfisted and shambolic scandal.
Oil companies had to do larger-scale, longer-term stuff like funding think tanks, lobbying politicians, and writing op-eds.
Now, because of prediction markets, the "attack surface" for interfering with scientific data collection is much larger and more fine-grained. The incentives for big oil companies probably haven't changed much… but now any random amoral idiot or degenerate gambler has an incentive to go find unguarded weather stations or water quality monitors, etc, and mess with them.
> A few years years ago, there was no conceivable profit motive for interfering with weather sensors on public property.
I have bad news for you. The manipulation of weather sensors for profit has a history that long pre-dates prediction markets. You just weren't paying attention until now.
> The manipulation of weather sensors for profit has a history that long pre-dates prediction markets.
Okay, I'm intrigued about what I've missed. Give me more information about this history, please.
Just wait until they start killing people to win bets.
It's going to happen.
It'll happy by proxy too. When they figure 90% of Tesla's or SpaceX's valuation is tied to Elon, suddenly he becomes your mark.
The total open interest of all major prediction markets is barely over a billion dollars. (1) That's the total amount of money currently wagered on ALL contracts across all platforms.
There are roughly 2,500 individual companies listed in the US alone with a market cap that exceeds 1 billion dollars. Tesla's market cap is 1.4 trillion - about 1,000 times the size of all prediction markets put together.
In other words, to the extent this incentive is of societal concern, it is not because of prediction markets - that is the tail wagging the dog.
Edit: to be clear I think these markets are a scourge as they currently operate, but not for this reason.
(1) https://predik.io/en/blog/open-interest-mercados-prediccion-...
This hypothetical situation had existed since the dawn of capital markets, or at least since the dawn of short selling. I don’t think we’ve ever seen anyone get assassinated to make a short bet pay off though.
And there is an obvious reason for this. Murder is very illegal. You therefore don't need short selling to be illegal because if someone sells short without killing anyone then that's fine, and if they do assassinate someone then you don't need to be able to charge them with short selling because you can charge them with murder.
Notice also that the murder is the thing you don't want happening in your jurisdiction, so that's the thing you have to prohibit anyway, because even if you ban short selling or prediction markets in your jurisdiction, having them in any other jurisdiction in the world would allow anyone to just place their bet there and you're right back to needing to deter that by punishing the murder rather than the bet.
Assassination markets where being discussed back in the 1990s.[1] I think it's been pretty clear for a while that "prediction" markets were going to arrive at the same place.
1. https://en.wikipedia.org/wiki/Assassination_market
In a sense, that's already happened. https://www.reuters.com/world/middle-east/kalshi-sued-over-o... and https://www.theguardian.com/world/2026/apr/18/iran-war-bets-...
> Later, a single user would make over $550,000 after betting that Ayatollah Ali Khamenei would topple, just moments before his assassination by Israeli forces.
It hasn't happened in this case. Your example has causality reversed. Khamenei wasn't killed because there was a prediction market about the political leadership of Iran.
On the other hand, given the regime’s desire to keep internal communications secret, maybe the causality does stem from the bet.
Don’t even need a gambling marketplace for that - could already put a massive short on TSLA and have a pop at Elon if you were so motivated.
I don't think you even need to attack anybody to do this. Just have an AI media package ready for the top-N CEOs, and wait for any incident involving their name and "injured", "hospital", "attacked", etc. Then short the stock, go to social media and show the CEO being transported in an ambulance, or a gurney with a sheet over it, "X still missing", whatever.
Probably automatable, and simply counting on automated systems and panic selling. Might be possible just with the AI package these days (not even requiring a traditional media article).
That has proven not to be the case with sports betting. Otherwise every major league pitcher would be needing armed guards to stop all the people with pipes trying to disable them. Seems there is at least some morality to not harm people but no issue in harming temperature sensors so where is the split line? Some really annoying ones like trains being on time can impact thousands yet i could see someone stepping out on tracks to make a train break to delay it to win a bet
> That has proven not to be the case with sports betting. Otherwise every major league pitcher would be needing armed guards to stop all the people with pipes trying to disable them.
This is a ridiculously over-broad claim.
First of all, prediction markets shift incentives in a pernicious way; they don't magically erase or override all pre-existing incentive structures.
And secondly, professional athletes of all stripes appear to be receiving a lot more threats of violence from gamblers (including "prediction market traders") than they were a few years ago.
In fact sports bodies are complaining of exactly that being the case, even in (especially in) much more obscure leagues than Major League Baseball (whose pitchers are compensated enough to cover their personal security):
'Decapitated bodies, death threats, that's our daily life': Tennis players, helpless targets of angry gamblers [ https://www.lemonde.fr/en/france/article/2025/12/08/decapita... ]
https://www.wtatennis.com/news/4288181/wta-and-itf-release-a...
When the vice industry kept gamblers mainly confined to their own community, it was ugly enough (see the “people with pipes” debt collection trope you refer to). I don’t see any good in letting those behaviors and motivations slop out onto the wider world uninvited.
“Forecasters incentivized by greed produce more accurate predictions in the aggregate” seems like an awfully skimpy fig leaf. If there’s really economically-relevant marginal value in tightening the error bars on every single forecast of every single indicator, in every measurable corner of human enterprise—then the betting parlors should be able to measure and demonstrate that; and the people who produce and rely on those indicators should be willing to pay something to capture the advantage, right?
I’d draw the morality line at, don’t bring gambling to anywhere that didn’t ask for it. If I—as the entity who incurs the cost to produce an indicator—want to hire the prediction market to run bets on it at arms’ length from me, fine. If not, no.
Not sure that he has done wonders for Tesla sales over the last few years, and he collected enemies quicker than most.
It's fine. People quickly forget the "bad stuff".
> Just wait until they start killing people to win bets.
Quite likely it has already happened.
There's been an enormous amount of betting on various military strikes by the Trump administration, much of which looks like insider trading.
Almost certainly there have been insiders with money on the line who were financially motivated to launch lethal attacks, which they might have otherwise paused or delayed.
Why almost certainly?
It's much more effective to make the decision first and the bet second.
Sure, but then what if in the several hours before the decision is executed, new information comes in?
Your decision maker is now going to make decisions differently than they would if they hadn’t made the bet, due to the financial incentive. It hopefully won’t be blatant, but they’re going to be more committed to the original decision.
> It's much more effective to make the decision first and the bet second.
What did I say that contradicts this?
> Why almost certainly?
Because I haven't seen any clear reporting with evidence documented down to the level of individual decision-making.
> What did I say that contradicts this?
I'm pointing out that the version where the market causes the decision is the much less effective way to do things. So I don't think it's so certain to have happened.
When the decision comes first it's still a problem but it's a very different problem.
I should make this explicit, I guess: If you make the decisions before betting, you don't really care what the market says beforehand, you'll make plenty of money either way.
(Having seen your edited and clarified comment, I think we basically agree.)
> the version where the market influences the decision is the much less effective way to do things.
Okay, so two possible scenarios: "market influences decision" and "decision influences market."
1. Polymarket offers a contract called something like: "Will the US launch any lethal boat strikes in the Caribbean on April 30, 2026?" A commander of a drone unit for the US military bets $500 on "yes". At 11:51pm on April 30, he's trying to decide whether or not to issue an order to fire on a boat, or to wait 15 minutes for better visual identification of the target. As a result of his bet on Polymarket, he's strongly incentivized to issue the order right now.
2. It's 11:51pm on April 30. A commander of a drone unit for the US military is reviewing images of a potential target boat. He idly opens a browser tab to Polymarket. Lo and behold, he sees that the odds of "Will the US launch any lethal boat strikes in the Caribbean on April 30, 2026?" are at only 0.3%. He's strongly incentivized to issue an order to strike right now and to quickly buy that Polymarket contract before news of the strike breaks.
Does it matter which of these two scenarios might actually be taking place? I don't think so.
The payout is much higher if you make an unlikely thing happen. "Unlikely things" in politics & warfare are probably highly correlated with irrational or irresponsible decisions.
> until us poor schmucks who just want an accurate temperature reading have to build a fortified compound in order to do so.
A fortified compound would affect the temperature reading.
Betting against what is widely considered as “expected”, “reasonable” is such a major source of profit when one can influence the income. Whether it’s a temperature sensor one can breathe on or movement of troops one can control or influence[0], the idea is the same—except in one of the above you can add “death and suffering” in addition to some unfortunate gamblers losing their money.
A depressing thought: it will only tip in favor of common good when the probability of something that we today consider “normal” becomes so small that betting on that finally becomes profitable to insiders with influence. Imagine that world…
[0] No, I’m not going to change my writing style because it is considered a “tell” of LLM use.
I don't mean to detract from your point, but regarding your footnote, you seemingly have. Unless it is in your writing style to make direct asides about how one may infer your message was procured.
I don't understand who is taking the other side of all these insane Polymarket bets. Is Polymarket doing it?
I've been quite successful trading weather prediction markets.
The prediction markets were never about predicting outcomes. If that's the level you are playing on, you're playing at the lowest possible level, and probably won't win.
The markets are now about properly modelling other peoples' manipulation of prediction. That's how Wall Street works as well. Companies can beat earnings and their stocks crash immediately after. It makes zero sense if you just model companies. It makes full sense if you stochastically model how an ensemble of humans behave under incentives and human-written bots behave under human-written policies.
"Hairdryer sometimes get pointed at the weather sensor" and "Government sometimes fudges jobs/CPI data" are more or less the same thing. Build it into your model. That's the level you need to play on to profit in these markets. It's not that different from how a chess engine works.
I don’t understand why these bets are allowed at all. Can one just make an account there and bet in anything?
The whole “prediction market” charade is increasingly proving to lend itself to abuse. I hope regulations catch up with it soon, otherwise more shenanigans will follow.
The problem is that the genie is out of the bottle, even if you try to regulate it away it pops up in offshore jurisdictions and uses crypto. The ease with which polymarket can be manipulated is infinite because there are so many different random things you can bet on. It's a sign of our times and I don't think there is much that can be done about it by anyone.
> offshore jurisdictions and uses crypto.
This vastly increases the barrier to entry for the normal person though. Is your position that just because laws don't work 100% of the time we shouldn't bother with them?
I didn't say that, you said that.
They didn't say you said it.
But wow what a useless way of conversing that is. They asked because it's unclear what you're implying. So could you please clarify if you think regulation would be useful? Or should be done despite being futile? Or shouldn't be done? I can only think of those three answers, is there another?
I think smart policy would be a good start. I just made a comment on the sign of our times. I could have worded my one line reply better. I do think it will be difficult to regulate as I don't see a political appetite to do so. Maybe some countries will get it right.
> It's a sign of our times and I don't think there is much that can be done about it by anyone.
Isn't cryptocurrency (for the most part) very traceable? If you make it too hard and risky for most people to participate in, you'll limit the negative effects. You could probably quite effectively discourage it by sanctioning any transactions with one of these markets, you've got some opportunity because at some point the cryptocurrency needs to be converted to/from cash.
Of course, you'd have to dedicate some investigative and enforcement resources to the effort.
If to bet on a prediction market you have to both use a VPN and launder your money like you're a drug dealer, and I don't think many people would do it.
> Isn't cryptocurrency (for the most part) very traceable
Mostly no. If you're connected it to a banking account, or other KYC platform, maybe, but the folks capable of doing that are part of the same administration supposedly doing the manipulation, so they would not investigate themselves.
Indeed, they are actually fighting against those trying to regulate it [0]
Indeed, the president's son works for Polymarket, and has invested in it [1]
0 –https://www.npr.org/2026/04/02/nx-s1-5771635/trump-cftc-kals...
1 – https://subscriber.politicopro.com/article/2025/08/polymarke...
>> Isn't cryptocurrency (for the most part) very traceable
> Mostly no. If you're connected it to a banking account, or other KYC platform, maybe,
But if you're (say) and American betting on it, the money almost certainly flows through one of those entities. And if you're using bitcoin the ledger is totally public, so you could track it from Coinbase (KYC) to whatever wallet the prediction market is using to accept payment (or vice versa).
> Indeed, they are actually fighting against those trying to regulate it [0]
Choosing to "do something about it" or not is a different question than can something be done at all. I was addressing the latter.
Bans from the AppStores will go a long way to removing this behavior. Sure a few die hards will always find a way to gamble, that does not mean we should not have regulations for the majority.
Making gambling illegal except in controlled places reduces the amount of people gambling.
The existence of illegal gambling is far less a problem than the issue of legal gambling from your phone.
We seem to be seeing the repetition of every stock/securities fraud that led to the creation of the SEC. But we're seeing people who refuse to let any reasonable regulation to happen.
They're banned in the USA and Europe, so you can't "just" make an account - you have to use a VPN.
Anything on the site? Yes. Anything at all? No - Polymarket themselves make the markets (and I think they have some partners that can make markets as well, but point is some random user cannot make a market).
Yep, you can bet on anything. Mike Selig is in charge of regulating it, and he's pretty zealous about suing any state regulators trying to exercise their right to regulate gambling. I think the days of the wild west are clearly numbered, but one guy with a burning passion and a big agenda (and the backing of Don Jr) can get a lot done in the meantime
Watching interviews with the CEO is cringe material to an extraordinary level.
As Ukrainian I find bets if some city would be captured - peak degeneracy. People are being sent to die or protecting their homes should not be someone bet.
John Oliver just did a segment on prediction markets. https://youtu.be/ZN4njIQcSR4
Turns out the US federal regulator is not doing their job, and is actively trying to prevent US states from imposing regulations.
I'm worried it will set the tone against all markets and trading, which would be very regrettable.
Unlikely regulators will do anything given Trump's son is involved with both companies.
Our zeitgeist is now "the grift is the goal."
There are communities larger than you'd expect around just about every topic imaginable. I'm certain there are temperature enthusiast groups, especially given its adjacency to climate stuff. It's probably going to be people mostly betting on something they have better than average knowledge of. I'd be interesting to compare the 'normal' majority temperature predictions from polymarket to local weather station predictions. I'm betting polymarket wins, by a wide margin.
For instance chess wagers on polymarket are super interesting because it's far more informative than a chess engine, even though engines are much stronger than any human. The nuance is that engines don't appreciate human factors like how easy/hard a position is to play. And so an engine might just say 'dead draw', whereas a strong human can say 'nah, white has very good winning chances here' - and the polymarket wagers end up reflecting that. And so there it's mostly strong players making money from people who think turning on their engine and betting based on what it says is something nobody else must have thought of.
gambling addicts is the answer
There's quite a lot of ways to interpret this question... but for that day's daily bet:
>A temperature of 18C was seen as a 99.6pc probability before the temperature spiked later in the day.
99.6% of them didn't take the insane bet. And at least one of those 0.4% (by value? count? idk) decided to cheat.
> 99.6% of them didn't take the insane bet.
I don't think the actual bet was insane, but the concept of betting on the weather is insane.
People bet on anything and everything, and the less controllable the better, afaict. "I'll bet you $5 that snail will eat the cucumber before the broccoli" - > "fuck yes, make it $20" is 100% a thing I could see happening. Weather is significantly easier to do every day though, unless you know a snail farmer with a twitch stream (if so, hook me up!).
It sounds like the other side of the bet was the actual winning bet when compared to Truth. Maybe they have great climate models and actually make a bet that they have an edge on. Maybe they have a gambling problem. Either way, they are the victims here.
They are the victims of Goodhart's law. The contract unambiguously said it would be decided by the reading of that particular thermometer.
If polymarket were staking wagers on its own platform, then it would have to worry about the integrity of the contracts, which is a nonstarter
You're wrong. The big prediction markets (Polymarket, Kalshi) employ in-house market makers and contractors. They provide liquidity for less-active contracts. They generally are not profitable.
Why do you think it’s a nonstarter when so many of these new platforms do commit fraud all the time and get away with it? It’s only a problem if they get caught, and then only if people actually pay attention enough to care
Casinos are purpose built to make you lose.
People still show up compulsively everyday.
Casinos have many games with exact payout odds posted. Polymarket does not.
So? There’s no game with payout odds in your favor.
Lotto (at least where I live) also shows the odds, which are always ridiculously low. Still, people play, because the human brain isn’t built to understand odds. It’s essentially worthless as a metric.
People with cryptocurrency and no idea what to do with it.
People that haven't read Black Swan and bet on every "sure bet" they can see
Nope the only money on the line is the people betting. Polymarket gets their cut and has "no monetary risk"
Kalshi places bets in their own marketplace - but they have all the data and lots of analysts, so the house still wins on average.
> While it is unclear how the temperature might have been manipulated, one possibility shared on weather forums was that a battery-powered hairdryer could have been used
Man I hate headline writers…
We’re I contracted to (legally and ethically) red team a temperature station, a “battery powered hair dryer” would be pretty low on my list of techniques for a number of reasons. First attempts would involve mirrors - parabolic or otherwise- to heat the device from a distance without potentially affecting wind speed / direction sensors.
Black cardboard stuck to the sensor and a transparent plastic bag around should do the trick with very little effort.
Or you could hold it until it ticks 18.9 or whatever the bet was.
Is it clear already how bad of an idea, and social disservice, Polymarket/Kalshi are?
> On April 15, one trader made $21,000 (£15,600) betting that the maximum temperature would not be 18 degrees, data from Polymarket show. A temperature of 18C was seen as a 99.6pc probability before the temperature spiked later in the day.
I believe that these are the specific Polymarket bets in question:
April 6 (https://polymarket.com/event/highest-temperature-in-paris-on...): this appears to have been something of a "test run", since the odds weren't particularly lopsided until it suddenly spiked in the evening local time.
April 15 (https://polymarket.com/event/highest-temperature-in-paris-on...): the odds were quite lopsided in favor of 18°C, until suddenly reversing in the evening. This is presumably where the fraudsters made all their money.
Between this and crypto cryptocurrencies (which obviously can be used to make bets) I don’t know which is more destructive to society
How is it even remotely as destructive as casinos, where the odds are always against you? From a probability perspective Polymarket is much more fair, as you actually have positive expected value if you have an information advantage.
Because Polymarket creates an incentive to change the real-world result.
If you create a bet on {person} getting assassinated by {date}, you greatly increase the chances of somebody on the "Yes" side thumbing the scales.
Yup. Gambling is already bad but somewhat contained within the walls of a casino or race track.
When you put money on the line for events that are influencable, things get dark fast.
Seemingly harmless sports betting is rife with stories about mob members going to extreme lengths to change the outcome of a sporting event.
It's not hard to see how bad a bet like "so and so won't show up to event x" can go. These don't have to be bets about killing or injuring people to result in people being killed or injured to win a bet.
These companies are a pox on society.
I know a fair number of people who go to a casino, spend a pre determined amount of money and as such, have fun.
Also, in roulette there's nowhere to put your money on whether a countries leader will be dead by the end of the month
I will make this argument in favor of casinos, which is that at least we have coevolved with them. They've been around for centuries. We collectively recognize the dangers. We are not collectively blindsided by them.
Individually, yeah, by all means they can prey on people. But they're on the list of things that have been preying on people for centuries, like alcohol, and all kinds of other things. Ring-fencing casinos has a track record of some success at containing them.
I mean, sure, I'd love to wake up tomorrow and for all of the human race to have advanced to the point that to every last individual we are no longer gambling and that industry vanishes in a puff of smoke. I am as far into the belief that they are immoral as it is practically possible to be. But they are at least a known and knowable risk.
These prediction markets are blindsiding us. We could put up with them for another few decades until we coevolve further with them, or we could just, you know, not. Just end them now. Plus, prediction markets have a certain meta-ness to them that casinos largely lack that will keep them fresh and coevolving their own new ways to predate on us. Casinos have basically reached their final form, prediction markets could take yet more decades to get there and it's possible there isn't a stable endgame with them. Or, again, we could just end them here and now.
I don't understand this logic. If people with information advantage get to cheat and win, then everyone without that advantage gets screwed. I struggle to see how this is even remotely "fair". It's like playing poker, but some players get to see what everyone's cards are.
Even humoring your logic begs the question: Why is monetizing an "information advantage" valuable to society?
The ingredient you are missing is fraud
Casinos are regulated and have to be much more transparent. In Europe and Australia slot machines are required to have appx min RTP (return-to-player) of 95%. With sportsbetting, bookmakers cannot just make up results. It's a dirty business preying on weak, but it's not hiding that.
Polymarket prediction results can be swayed by whales and differ from reality. Example: they ruled Tesla unsupervised full selfdriving a real usable feature in ~Feb 2026. It still doesn't exist and won't. This decision is far from being the only such one.
Fiat money is obviously more destructive, but you'd have to do some basic research to figure that out.
Here's a thought experiment for you: if "fiat currency=bad" and "hard money=good", why did the world collectively switch? Where are all the prosperous societies that held the line?
There is an answer the crypto enthusiasts have to this, but since I'm not one of them I wouldn't do the argument justice.
The short version is, it's about control and power.
Wonder how the founders/board/investors of the bad incentives factory would manage their site after a massive crowdfunding campaign bet that they'd all still be alive in 2027.
Why is Polymarket legal? I just don't understand.
For a while it wasn’t in the US. They now have a cut-down version. But a lot of people use VPNs to access the less-restricted international version. So to answer your question, a lot of users are using it in a way that’s illegal.
It and Kalshi are not. But we don't have regulators that want to enforce the law here.
Polymarket in particular started out using crypto and off shoring with a "not legal in the US, wink wink" to get try and dodge regulations.
Why wouldn't it be
https://en.wikipedia.org/wiki/Insider_trading
It creates financial incentives for anti-social behavior and the proposed benefits of it being a way to determine truth are dubious and self-serving and would not be worth the societal cost regardless.
Remember when it was just common sense that letting people gamble on things would undermine the integrity of those things?
The critics of prediction markets needs to decide if they are against the markets because they are gambling, or because they aren't gambling.
At some point, the market for markets will demand better regulation than this. But I find it a little absurd that anyone is still putting their money into these markets with story after story of obvious fraud.
> I find it a little absurd that anyone is still putting their money into these markets with story after story of obvious fraud.
Then you do not understand gamblers. They make emotional decisions not rational decisions. That's why the lottery works (i.e. "someone has to win")
They spent a lot on marketing, it doesn't surprise me at all
Cheating with weather sensor is not new.
Wrecked rain gauges. Whistleblowers. Million-dollar payouts and manhunts.
https://news.ycombinator.com/item?id=41485560
Hair dryer? Or something like a mirror from a comfortable distance?
Reminds me of when I made about $40k finding a source that had CO2 data in close to real time when other people were tracking one about 12 hours delayed
See https://misinfounderload.substack.com/p/tales-from-predictio...
Those are great stories in the article!
If you have 3 minutes, here's an apropos BBC audio comedy sketch.
https://youtu.be/ub01udUz7ns?si=OBMKdK6RED3aZMEq&t=15
Reminds me of not long ago someone writing about "Everything is Lies Now"
Idea : "Manipulation of real world events because correct prediction of real world events is incentivized."
Try to scale this anywhere from hairdryer usage to trip temp sensors to nuclear bombs going off in poor countries.
John Oliver had a segment on prediction markets this week. It covers insider training and opportunities for blatant manipulation like this, well worth checking out. The example in the Last Week Tonight segment was betting on dildos being thrown on court during a WNBA match. And then travelling to the match to throw the dildo.
[0] https://www.youtube.com/watch?v=ZN4njIQcSR4
The WNBA bit was less alarming than the betting on various aspects of the US + Israel versus Iran war.
All gross.
Why is the WNBA alarming at all (other than the fact that we shouldn't be throwing dildos on the court at all, of course)?
I'm just not sure why anyone would take a bet against someone who can single handedly make their side win. It would be like someone making a bet that I won't eat a hot dog for lunch tomorrow. Of course I'm going to eat a hot dog for lunch tomorrow. Why is there anything alarming about that? It's just stupid that anyone is taking the other side of that bet.
> While it is unclear how the temperature might have been manipulated, one possibility shared on weather forums was that a battery-powered hairdryer could have been used, according to Le Monde newspaper.
Clickbait headline FWIW.
Flag the submission.
Telegaph is a disreputable tabloid. There are better sources.
https://www.tradingview.com/news/cointelegraph:1c00dcc26094b...
Outside Trading.
The guy will be solely responsible for half a degree of global warming next year.
Beautiful con, tbh. I don't welcome this behavior (borderline criminal), but you have to admit - well played.
well over the border
Which law? I genuinely don't know. These prediction markets are new enough that I'm not sure if the laws have been written yet.
The libertarian argument for prediction markets is really beautiful.
It's just a pity it basically depends on all participants in the prediction market being basically unaware that they are participating in a prediction market, and being oblivious to the incentives to create the outcomes they are predicting by the very act of predicting it with money.
But other than that minor detail, that little minor catastrophic flaw in the foundation, it's a beautiful argument.
I think we can call it as a society. It's a failure. We can go back to banning them, not just for moral reasons, but just pragmatic ones. The theory doesn't work. The supposed benefits don't manifest, and "unanticipated" costs to everyone do. We did the experiment. (Again.) We can close this out now.
Fun fact: Kalshi runs ads that start with a guy saying "I just made money because it snowed!"
Make of that what you will.
[dupe] https://news.ycombinator.com/item?id=47869664
Quite literally EVERYTHING around us is now subject to possible manipulation by these idiots if they think they can profit.
Even the US Government has executive and legislative officials profiting from secret information they know from doing their duties.
I wonder when someone who does cloud seeding will place a bet about rain at some unlikely time and place.
Or the next large forest fire.
Not only is everything subject to manipulation, but it’s incentivized—with a new opportunity to capitalize on the unwitting.
And as a result we should gain stronger epistemology. How many cities base their official temperature readings on just a few sensors rather than a widespread network?
Sure you might argue, maybe this was an issue with Polymarket choosing a weak source rather than the gov, but is that really true? If you question measurements like this you quickly get labeled an climate denier.
IMO this is good for the world, temp measurements should be based on thousands of sensors not just one. And if cloud seeding works, all the better for humanity, it's likely a key to terraforming future planets.
You completely missed the issue. Météo-France already has tens of thousands of stations across the country, they're very obviously not basing their entire models off of one sensor in Paris CDG.
The degenerate idiots from Polymarket bet on this particular sensor. There's no law preventing people from betting on single sensors. And we can't make laws preventing people from acting on the world in all the diverse ways that can be exploited to cheat in prediction market.
We should just blanket ban this negative-value industry. We don't want people betting on forest fires and then starting them.
> I wonder when someone who does cloud seeding will place a bet about rain at some unlikely time and place.
Each year, one of my state's legislators introduces a bill to outlaw chemtrails [0]. It never leaves committee. This year, he added the plot of Termination Shock [1] to his bill. This proposed legislation already includes "cloud seeding" as a crime. Penalty of $500k/day and each day is a separate crime.
0 - https://apps.legislature.ky.gov/record/26rs/hb60.html
1 - https://en.wikipedia.org/wiki/Termination_Shock_(novel)#
Now bet that climate denials will use this as example that lots of temperature data is faked.