One of the few aspects of my job I enjoy more than designing a new market is actually building it. Turning some wild concept that sprung from the minds of a bunch of scientists into a working artifact is a huge rush, and I can only smile as people from around the world commence tinkering with the thing, often in ways I never expected. The “build it” phase of a research project, besides being a ton of fun, inevitably sheds important light back on the original design in a virtuous cycle.

In that vein, I am thrilled to announce the beta launch of PredictWiseQ, a fully operational example of our latest combinatorial prediction market design: “A tractable combinatorial market maker using constraint generation”, published in the 2012 ACM Conference on Electronic Commerce.

You read the paper.1  Now play the game.2 Help us close the loop.

PredictWiseQ Make-a-Prediction screenshot October 2012

PredictWiseQ is our greedy attempt to scarf up as much information as is humanly possible and use it, wisely, to forecast nearly every possible detail about the upcoming US presidential election. For example, we can project how likely it is that Romney will win Colorado but lose the election (6.2%), or that the same party will win both Ohio and Pennsylvania (77.6%), or that Obama will paint a path of blue from Canada to Mexico (99.5%). But don’t just window shop, go ahead and customize and buy a prediction or ten for yourself. Your actions help inform the odds of your own predictions and, crucially, thousands of other related predictions at the same time.

For example, a bet on Obama to win both Ohio and Florida can automatically raise his odds of winning Ohio alone. That’s because our market maker knows and enforces the fact that Obama winning OH and FL can never be more likely than him winning OH. After every trade, we find and fix thousands of these logical inconsistencies. In other words, our market maker identifies and cleans up arbitrage wherever it finds it. But there’s a limit to how fastidious our market maker can be. It’s effectively impossible to rid the system of all arbitrage: doing so is NP-hard, or computationally intractable. So we clean up a good bit of arbitrage, but there should be plenty left.

So here’s a reader’s challenge: try to identify arbitrage on PredictWiseQ that we did not. Go ahead and profit from it and, when you’re ready, please let me and others know about it in the comments. I’ll award kudos to the reader who finds the simplest arbitrage.

Why not leave all of the arbitrage for our traders to profit from themselves? That’s what nearly every other market does, from Ireland-based Intrade, to Las Vegas bookmakers, to the Chicago Board Options Exchange. The reason is, we’re operating a prediction market. Our goal is to elicit information. Even a completely uninformed trader can profit from arbitrage via a mechanical plug-and-chug process. We should reserve the spoils for people who provide good information, not those armed (solely) with fast or clever algorithms. Moreover, we want every little crumb of information that we get, in whatever form we get it, to immediately impact as many of the thousands or millions of predictions that it relates to as possible. We don’t want to wait around for traders to perform this propagation on their own and, besides, it’s a waste of their brain cells: it’s a job much better suited for a computer anyway.

Intrade offers an impressive array of predictions about the election, including who will win in all fifty states. In a sense, PredictWiseQ is Intrade to the 57th power. In a combinatorial market, a prediction can be any (Boolean) function of the state outcomes, an ungodly degree of flexibility. Let’s do some counting. In the election, there are actually 57 “states”: 48 winner-takes-all states, Washington DC, and two proportional states — Nebraska and Maine — that can split their electoral votes in 5 and 3 unique ways, respectively. Ignoring independent candidates, all 57 base “states” can end up colored Democratic blue or Republican Red. So that’s 2 to the power 57, or 144 quadrillion possible maps that newscasters might show us after the votes are tallied on November 6th. A prediction, like “Romney wins Ohio”, is the set of all outcomes where the prediction is true, in this case all 72 quadrillion maps where Ohio is red. The number of possible predictions is the number of sets of outcomes, or 2 to the power 144 quadrillion. That’s more than a googol, though less than a googolplex (maybe next year). To get a sense of how big that is, if today’s fastest supercomputer starting counting at the instant of the big bang, it still wouldn’t be anywhere close reaching a googol yet.

Create your own league to compare your political WiseQ among friends. If you tell us how much each player is in for, we’ll tell you how to divvy things up at the end. Or join the “Friends Of Dave” (FOD) league. If you finish ahead of me in my league, I’ll buy you a beer (or beverage of your choice) the next time I see you, or I’ll paypal you $5 if we don’t cross paths.

PredictWiseQ is part of PredictWise, a fascinating startup of its own. Founded by my colleague David Rothschild, PredictWise is the place to go for thousands of accurate, real-time predictions on politics, sports, finance, and entertainment, aggregated and curated from around the web. The PredictWiseQ Game is a joint effort among David, Miro, Sebastien, Clinton, and myself.

The academic paper that PredictWiseQ is based on is one of my favorites — owed in large part to my coauthors Miro and Sebastien, two incredible sciengineers. As is often the case, the theory looks bulletproof on paper. But I’ve learned the hard way many times that you don’t really know if a design is good until you try it. Or more accurately, until you build it and let a crowd of other people try it.

So, dear crowd, please try it! Bang on it. Break it. (Though please tell me how you did, so we might fix it.) Tell me what you like and what is horribly wrong. Mostly, have fun playing a market that I believe represents the future of markets in the post-CDA era, a.k.a the digital age.

__________
1 Or not.
2 Or not.

In late 2010, I began talking to a very early-stage startup named Slipjockey, based in Salt Lake City. When we first started corresponding, Slipjockey was little more than a good idea coupled with some very basic technology and passionate co-founders. In the time since, Slipjockey has taken appropriate steps to bring their concept to market, including securing a favorable legal opinion and filing a patent for their technology.

The core concept of Slipjockey is ingenious. It’s a marketplace for buying and selling Las Vegas bet slips. The process starts when someone makes a bet at a licensed Nevada race and sports book. If he or she wants to sell the bet slip for whatever reason — suppose the predicted team is winning in a landslide at halftime and the slip has doubled in value — they can log onto Slipjockey and list it for sale. Another Slipjockey user may agree to buy it. The buyer takes ownership of the bet slip and he or she can keep it or resell it again to another Slipjockey user, etc. The final owner of any bet slip is paid in full directly from the sports book that originally issued the ticket.

Real-time trading on Slipjockey is similar to the action on betting exchanges like Betfair. The key difference is that all wagers must originate from a licensed Nevada race and sports book where gambling is legal.

The Slipjockey business concept grew from the notion that handicappers should have an option other that win, lose, or push. Slipjockey provides that fourth option by enabling handicappers to terminate their outcome risk, locking in a gain or avoiding a total loss prior to the end of the event. With the growth in live betting (aka “in-running betting”) around the world, and in Las Vegas courtesy of Cantor Fitzgerald, it’s clearly an option that people want.

Initially, Slipjockey is focused on launching with coverage of US football, tennis, and golf before expanding into other sports.

I’ve spoken mainly with Ryan Eads and his brother Rory, two of the co-founders. They are smart, well spoken, and tireless entrepreneurs. I have every expectation that, to the extent this idea has wings — and I believe it does — they will make it fly.

The first question you’re likely to ask is: is this legal? Indeed, that’s the first question I asked Ryan. As a pre-condition to launching, he secured a legal opinion from a former Nevada Gaming Control Board attorney that says, in effect, that because bets originate in Las Vegas and are ultimately paid out in Las Vegas, the Slipjockey exchange is legal. The attorney’s opinion is just that: an opinion, and not a guarantee. But it is convincing and credible. Certainly Slipjockey users are safe.

Currently, Slipjockey is inviting users to participate in a soft launch for trading National Football League games. To participate, create a profile at www.slipjockey.com and send an email to info@slipjockey.com. Mention that you read my blog post and I’m sure they’ll send you an invitation containing all the details if they have spots remaining.

Crowdpark logoCrowdpark is an impressive, well-designed prediction market game that’s already attracted 500,000 monthly active users on Facebook, the 11th fastest growing Facebook app in April.

It’s a dynamic betting game with an automated market maker, not unlike Inkling Markets in functionality (or even Predictalot minus the combinatorial aspect). What stands out is the flashy UI, both literally and figuratively. The look is polished, slick, refreshing, and richly drawn. It’s also cutesy, animation-happy, and slow to load. Like I said, Flash-y in every way. The game is well integrated into Facebook and nicely incorporates trophies and other social rewards. Clearly a lot of thought and care went into the design: on balance I think it came out great.

Crowdpark is a German company with an office in San Francisco. In addition to their Facebook game, they have German and English web versions of their game, and white-label arrangements with gaming companies. They launched in English just last December.

Crowdpark’s stunning growth contrasts with decidedly more mixed results on this side of the Atlantic. I wonder how much of Crowdpark’s success can be attributed to their German roots, their product, their marketing, or other factors?

Crowdpark has an automated market maker they call “dynamic betting” that I can’t find any technical details about [1]. Here’s their well-produced video explanation:

They say it’s “patent pending”, though my colleague Mohammad Mahdian did some nice reverse engineering to show that, at least in their Facebook game, they’re almost certainly using good-old LMSR. Here is a graph of Crowdpark’s market maker price curve for a bet priced at 1%:

Crowdpark's automated market maker price curve

Here is the raw data and the fit to LMSR with b=20,000.

risk   to win (CP)   to win (LMSR)
1 91 91.079482
2 181 181.750593
5 451 451.350116
10 892 892.847929
20 1747 1747.952974
50 4115 4115.841760
100 7535 7535.378665
200 13019 13019.699483
500 23944 23944.330406
600 26594 26594.687310
700 28945 28945.633048
800 31059 31059.076097
900 32979 32979.512576
1000 34740 34740.000000


Still, there’s a quote buried in the video at 0:55 that caught my attention: “you’re current profit is determined by the fluctuation of the odds”.

There’s only one market maker that I know of where the profit fluctuates with the odds, and that’s my own dynamic parimutuel market, which by coincidence recently went from patent pending to inventor cube delivered. :-)

David Pennock's dynamic parimutuel market (DPM) patent cube - 4/2011

With every other market maker, indeed almost every prediction market, the profit is fixed at the time of the bet. Add to that the fact that Crowdpark bought a majority stake in Florida horse racing circuit Saratoga Racing Inc. and plans to operate all bets exclusively through their system, leads me to wonder if they may have some kind of parimutuel variant, the only style of betting that is legal in the US.

Of course, it may be that I simply misinterpreted the video.


[1] The technical exec at Crowdpark seems to be Aleksandar Ivanov. I found a trade press paper on (internal) prediction markets he wrote in 2009 for the Journal of Business Forecasting.

Cantor Gaming mobile device for in-running bettingLast January, a few friends and I visited the sportsbook at the M Casino in Las Vegas, one of several sportsbooks now run by Cantor Gaming, a division of Wall Street powerhouse Cantor Fitzgerald. Traditional sportsbooks stop taking bets when the sporting event in question begins. In contrast, Cantor allows “in-running betting”, a clunky phrase that means you can bet during the event: as touchdowns are scored, interceptions are made, home runs are stolen, or buzzers are beaten. Cantor went a step further and built a mobile device you can carry around with you anywhere in the casino to place your bets while watching games on TV, drink in hand. (Cantor also runs spread-betting operations in the UK and bought the venerable Hollywood Stock Exchange prediction market with the goal of turning it into a real financial exchange; they nearly succeeded, obtaining the green light from the CFTC before being shut down by lobbyists, er, Congress.)

Back to the device. It’s pretty awesome. It’s a Windows tablet computer with Cantor’s custom software — pretty well designed considering this is a financial firm. You can bet on the winner, against the spread, or on one-off propositions like whether the offensive team in an NFL game will get a first down, or whether the current drive will end with a punt, touchdown, field goal, or turnover. The interface is pretty nice. You select the type of bet you want, see the current odds, and choose how much you want to bet from a menu of common options: $5, $10, $50, etc. You can’t bet during certain moments in the game, like right before and during a play in football. When I was there only one game was available for in-running betting. Still, it’s instantly gratifying and — I hate to use this word — addictive. Once my friend saw the device in action, he instantly said “I’m getting one of those”.

When I first heard of Cantor’s foray into sports betting, I assumed they would build “betfair indoors”, meaning an exchange that simply matches bettors with each other and takes no risk of its own. I was wrong. Cantor’s mechanism is pretty clearly an intelligent automated market maker that mixes prior knowledge and market forces, much like my own beloved Predictalot minus the combinatorial aspect. Together with their claim to welcome sharps, employing a market maker means that Cantor is taking a serious risk that no one will outperform their prior “too much”, but the end result is a highly usable and impressively fun application. Kudos to Cantor.


P.S. Cantor affectionately dubbed their oracle-like algorithm for computing their prior as “Midas”, proving this guy has a knack for thingnaming.

Michael Mitzenmacher recently made a “First they came…” argument, and now I will too.

Even if you detest gambling, this should send a chill down your spine: the FBI seized the domain names of several poker websites who operate offshore and arrested their owners.

The action exposes the lie that the US government does not control the Internet or does not exercise that control and perhaps hastens the day of a fragmented Internet. It’s an example of the government’s hypocritical position on Internet freedom: how can we express outrage at countries that block facebook or censor google when our own country seizes domain names and, in another recent example, tries to pass an Internet Blacklist Bill to block file-sharing websites? To the hundreds of thousands who spoke out against the latter, kudos, but I submit that the former poses just as dangerous a slippery slope.

These companies are obeying the laws of the countries in which they are based. Who are we to block them let alone seize their Internet property?

Update 2011/05/11: More scary developments in net censorship.

Today, Yahoo! placed two full-page ads on the back cover of the Times of India, the largest English-language daily in the world, to promote Yahoo! Cricket, a site that reaches 13.4 percent of everyone online in India and serves as the official website of the ICC Cricket World Cup.

Take a look at the middle right of the second page: it says “Play exciting games and win big” and features… Predictopus! That’s the Indian spinoff of Predictalot, the combinatorial prediction game I helped invent.

Page 1 of two full-page Yahoo! Cricket ads in the Times of India, p. 31, 2011/03/30Predictopus on Page 2 of two full-page Yahoo! Cricket ads in the Times of India, p. 32, 2011/03/30

Predictopus has nearly 70,000 users and counting, and this ad certainly won’t hurt.

Yahoo!!!

BTW, I grabbed these images from an amazing site called Press Display, which I discovered via the New York Public Library.

Times of India Mumbai edition
30 Mar 2011

Times of India Mumbai edition
30 Mar 2011

Also, congrats India, and thanks! I nearly doubled my virtual bet with the victory:

Dave's Predictopus prediction: India will advance further than Pakistan, 3/2011

March Madness is upon us and Predictalot, the crazy game that I and others at Yahoo! Labs invented, is live again and taking your (virtual) bets. Filling out brackets is so 2009. On Predictalot, you can compose your own wild prediction, like there will be exactly seven upsets in the opening round, or neither Duke, Kentucky, Kansas, nor Pittsburgh will make the Final Four. You’ll want your laptop out and ready as you watch the games — you can buy and sell your predictions anytime, like stocks, as the on-court action moves for or against you.

Predictalot v0.3 is easier to play. We whittled down the ‘Make Prediction’ process from four steps to just two. Even if you don’t want to wager, with one click come check out the projected odds of nearly any crazy eventuality you can dream up.

Please connect to facebook and/or twitter to share your prediction prowess with your friends and followers. You’ll earn bonus points and my eternal gratitude.

The odds start off at our own prior estimate based on seeds and (new this year) the current scores of ongoing games, but ultimately settle to values set by “the crowd” — that means you — as predictions are bought and sold.

Yahoo! Labs Predictalot version 0.3 overview tab screenshot

For the math geeks, Predictalot is a combinatorial prediction market with over 9 quintillion outcomes. Prices are computed using an importance sampling approximation of a #P-hard problem.

What kind of information can we collect that a standard prediction market cannot? A standard market will say that Texas A&M is unlikely to win the tournament. Our market can say more. Yes, A&M is unlikely to reach the Final Four and even more unlikely to win apriori, but given that they somehow make it to the semifinals in Houston, less than a two hour drive from A&M’s campus, their relative odds may increase due to a home court advantage.

Here’s another advantage of the combinatorial setup. A standard bookmaker would never dare to offer the same millions of bets as Predictalot — they would face nearly unlimited possible losses because, by tradition, each bet is managed independently. By combining every bet into a single unified marketplace, we are able to limit the worst-case (virtual) loss of our market maker to a known fixed constant.

Abstracts are due today for the Third International Conference on Prediction and Information Markets. It will be held in Nottingham, England April 3-5 along with two related conferences: the International Conference on Gambling Studies and the International Conference on Money, Investment and Risk. (Abstracts also due today for both of these conferences.)

I’ve been considering submitting some thing(s): I’m curious if anyone else is planning to submit or attend?

Date: 3 – 5 April 2011
Event: Third International Conference on Prediction and Information Markets
Location: Nottingham Conference Centre
Organiser: Nottingham Business School

Details:

The Third International Conference on Prediction and Information Markets will be held in association with Economic Issues and the Journal of Prediction Markets.

Prediction / information markets offer a way of harnessing the wisdom of crowds. They have been used to aggregate information in order to provide forecasts of a wide range of events…

In recent years, a number of companies have employed these markets as a means of aggregating the information dispersed widely among their employees and customers…

Call for papers and presentations
Please send an abstract (maximum of 200 words) to Professor Leighton Vaughan Williams by email, by the closing date for receipt of abstracts of Monday 21 February 2011. Confirmation of receipt of abstracts will be sent within a maximum of five working days.

Yahoo! India Predictopus logo

I’m thrilled to report that Predictalot had an Indian makeover, launching as Predictopus* for the ICC Cricket World Cup. The Yahoo! India team did an incredible job, leveraging the idea and some of the code base of Predictalot, yet making it their own. Predictopus is not a YAP — it lives right on the Yahoo! Cricket website, the official homepage for the ICC Cricket World Cup. They’re also giving away Rs 10 lakhs — or about $22,000 if my calculations are correct — in prizes. Everything is bigger in India, including the crowds and the wisdom thereof. It will be great to see the game played out on a scale that dwarfs our college basketball silliness in the US.

The Y! India team reused some of the backend code but redid the frontend almost entirely. To adapt the game to cricket, among other chores, we had to modify our simulation code to estimate the starting probabilities that any team would win against any other team, even in the middle of a game. (How likely is it for India to come back at home from down 100 runs with 10 overs left and 5 wickets lost? About 25%, we think.) These starting probabilities are then refined further by the game-playing crowds.

It’s great to see an experiment from Labs grow into a full-fledged product run by a real product team in Yahoo!, a prime example of technology transfer at its best. In the meantime, we (Labs) are still gunning for a relaunch of Predictalot itself for March Madness 2011, the second year in a row. Stay tuned.

2011/02/24 Update: An eye-catching India-wide ad campaign for predictopus is live, including homepage, finance, movies, OMG, answers, mail, everywhere! Oh, and one of the prizes is a Hyundai.

predictopus ad on Yahoo! India homepage 2011/02/24


* Yes, that’s a reference to legendary Paul the Octopus, RIP.

HP research scientist Vinay Deolalikar has constructed the most credible proof yet of the most important open question in computer science. If his proof is validated (and there are extremely confident skeptics as you’ll see) he proved that P≠NP, or loosely speaking that some of the most widespread computational problems — everything from finding a good layout of circuits on a chip to solving Sudoku puzzles to computing LMSR prices in a combinatorial market — cannot be solved efficiently. Most computer scientists believe that P≠NP, but after decades of some of the smartest people in the world trying, and despite the promise of worldwide accolades and a cool $1 million from the Clay Mathematics Institute, no one has been able to prove it, until possibly now.

Scott Aaronson is a skeptic, to say the least. He made an amazing public bet to demonstrate his confidence. He pledged that if Deolalikar wins the $1 million prize, Aaronson will top it off with $200,000 of own money. Even more amazing: Aaronson made the bet without even reading the proof. [Update: I should have said "without reading the proof in detail": see comments] (Perhaps more amazing still: a PC World journalist characterized Aaronson’s stance as “noncommittal” without a drip of sarcasm.) [Hat tip to Dan Reeves.]

As Aaronson explains:

The point is this: I really, really doubt that Deolalikar’s proof will stand. And while I haven’t studied his long, interesting paper and pinpointed the irreparable flaw… I have a way of stating my prediction that no reasonable person could hold against me: I’ve literally bet my house on it.

Aaronson is effectively offering infinite odds [Update: actually more like 2000/1 odds: see comments] that the question “P=NP?” will not be resolved in the near future. Kevin McCurley and Ron Fagin made a different (conditional) bet: Fagin offered 5/1 odds (at much lower stakes) that if the question is resolved in 2010, the answer will be P≠NP. Bill Gasarch says that he, like Aaronson, would bet that the proof is wrong… if only he were a betting man. Richard Lipton recounts a discussion about the odds of P=NP with Ken Steiglitz.

But beyond a few one-off bets and declarations, where is the central market where I can bet on P=NP? I don’t even necessarily want in on the action, I just want the odds. (Really!)

My first thought was the Foresight Exchange. It does list one related contract — Good 3SAT Algorithm by 2020 — which should presumably go to zero if Deolalikar’s proof is correct. It hasn’t budged much, consistent with skepticism (or with apathy). My second thought was the PopSci Predictions Exchange (PPX), though sadly it has retired. InklingMarkets has a poll about whether P=NP will be resolved before the other Clay Institute prize questions, but not about how it will be resolved or the odds of it happening. (The poll is one of several markets sponsored by the Woodrow Wilson Center’s Science and Technology Innovation Program — hat tip to Vince Conitzer.) I don’t see anything at longbets, and anyway longbets doesn’t provide odds despite it’s name.

In 1990 Robin Hanson provocatively asked: Could gambling save science?. That question and his thoughtful answers inspired a number of people, including me, to study prediction markets. Indeed, the Foresight Exchange was built largely in his image. P=NP seems one of the most natural claims for any scitech prediction market.

All these years later, when I really need my fix, I can’t seem to get it!


2010/08/14 Update: Smarkets comes the closest: they have real-money betting on whether P=NP will be resolved before the other Clay Institute prize questions. They report a 53% chance as of 2010/08/14 (for the record, I would bet against that). What’s missing is when the award might happen and how the question might be resolved, P=NP or P≠NP. I also don’t see a graph to check whether Deolalikar’s proof had any effect.

If it wasn’t clear in my original post, I found Aaronson’s bet incredibly useful and I am thrilled he did it. I believe he should be commended: his bet was exactly what more scientists should do. Scientists should express their opinion, and betting is a clear, credible, and quantitative way to express it. It would be as shame if some of the negative reactions caused him or others not to make similar bets in the future.

I just wish there were a central place to make bets on scientific claims and follow the odds in the vision of Robin Hanson, rather than every scientist having to declare their bet on their own individual blogs.

Translate this Page

© 2010 Oddhead Blog Suffusion WordPress theme by Sayontan Sinha

resume writing services