Why should you try Predictalot?

• Gamers: Make almost any prediction you can think of about March Madness, the NCAA men’s basketball tournament.
• Sports fans: Check the crowd’s odds: Is St. Mary’s the next Cinderella?
• Economists: Play with a true combinatorial prediction market with 9.2 quintillion outcomes and a single pool of liquidity, unlike almost any other of today’s financial and prediction markets.
• Geeks: Ponder some of the interesting computer science challenges, including approximating #P-hard problems and an eerily similar sampling problem as faced by physicists.
• Everybody’s doing it.
• Barack Obama might do it, according to VentureBeat on NYTimes.com: “President Barack Obama will likely be busy this week [but]… maybe he’ll be able to sneak a peek at Predictalot on his BlackBerry between meetings.”

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Most published papers on prediction markets (there aren’t many) paint a wildly rosy picture of their accuracy. Perhaps it is because many of these papers are written by researchers having affiliations with prediction market vendors.

Robin Hanson is Chief Scientist at Consensus Point. I like his ideas about combinatorial markets and market scoring rules, but I think he over-sells the accuracy and usefulness of prediction markets. His concept of Futarchy is an extreme example of this. Robin loves to cite HP’s prediction markets in his presentations. Emile Servan-Schreiber (Newsfutures) is mostly level-headed but still a big fan of prediction markets. Crowdcast’s Chief Scientist is Leslie Fine; their Board of Advisors includes Justin Wolfers and Andrew McAfee. Leslie seems to have a more practical understanding than most, as evidenced by this response to the types of questions that Crowdcast’s prediction markets can answer well: “Questions whose outcomes will be knowable in three months to a year and where there is very dispersed knowledge in your organization tend to do well.” She gets it that prediction markets aren’t all things to all people.

An Honest Paper

To some extent, all of the researchers over-sell the accuracy and the range of useful questions that may be answered by prediction markets. So, it is refreshing to find an honest article written about the accuracy of prediction markets. Not too long ago, Sharad Goel, Daniel M. Reeves, Duncan J. Watts, David M. Pennock published Prediction Without Markets. They compared prediction markets with alternative forecasting methods for three types of public prediction markets: Football and baseball games and movie box office receipts.

They found that prediction markets were just slightly more accurate than alternative methods of forecasting. As an added bonus, these researchers considered the issue that prediction market accuracy should be judged by its effect on decision-making. So few researchers have done this! A very small improvement in accuracy is not considered material (significant), if it doesn’t change the decision that is made with the forecast. It’s a well-established concept in public auditing, when deciding whether an error is significant and requires correction. I have discussed this concept before.

While they acknowledge that prediction markets may have a distinct advantage over other forecasting methods, in that they can be updated much more quickly and at little additional cost, they rightly suggest that most business applications have little need for instantaneously updated forecasts. Overall, they conclude that “simple methods of aggregating individual forecasts often work reasonably well relative to more complex combinations (of methods).”

For Extra Credit

When we compare things, it is usually so that we can select the best option. In the case of prediction markets it is not a safe assumption that the choices are mutually exclusive. Especially in enterprise applications, prediction markets are heavily dependent on the alternative information aggregation methods as a primary source of market information. Of course, there are other sources of information and the markets are expected to minimize bias to generate more accurate predictions.

In the infamous HP prediction markets, the forecasts were eerily close to the company’s internal forecasts. It wasn’t difficult to see why. The same people were involved with both predictions! The General Mills prediction markets showed similar correlations, even when only some of the participants were common to both methods. The implication of these cases is that you cannot replace the existing forecasting system with a prediction market and expect the results to be as accurate. The two (or more) methods work together.

Not only do most researchers (Pennock et al, excepted) recommend adoption of prediction markets, based on insignificant improvements in accuracy, they fail to consider the effect (or lack thereof) on decision-making in their cost/benefit analysis. Even if some do the cost/benefit math, they don’t do it right.

Where a prediction market is dependent on other forecasting methods, the marginal cost is the total cost of running the market. There is no credit for eliminating the cost of alternative forecasting methods. The marginal benefit is that expected by choosing a different course of action than the one that would have been taken based on a less accurate prediction. That is, a slight improvement in prediction accuracy that does not change the course of action has no marginal benefit.

Using this approach, a prediction market that is only “slightly” more accurate, than those from alternative forecasting approaches, is just not good enough. So far, there is little, if any, evidence that prediction markets are anything more than “slightly” better than existing methods. Still, most of our respected researchers continue to tout prediction markets. Even a technology guru like Andrew McAfee doesn’t get it , in this little PR piece he wrote, shortly after joining Crowdcast’s Board of Advisors.

Is it a big snow job or just wishful thinking?

[Cross-posted from Toronto Prediction Market Blog]

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No one who makes a living trading really cares about EMH, but I’m not sure why failure to predict under EMH is that surprising. Markets do more discounting than predicting. That’s part of the reason why stocks are volatile — the last data point tends to be extrapolated into perpetuity. It is true that factors like emotion and momentum additionally move prices, but to me this points to a fundamental challenge in valuation: the idea that there is an “intrinsic” value, when in fact all values interact, with prices reflecting structural realities and other prices. The misallocation in the housing bubble was to some extent already a mispricing of money in the form of rates. What was the “right” price for housing given the price of money?

The price of money in turn was influenced by the demographic savings glut that previously fueled the tech bubble. At this point, governments failing to predict the past — the trend of increased longevity — seems like the biggest problem. The escalated contentiousness in the Senate is, in part, a symptom of this slow motion failure and the “lower stakes” for all of us.

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“The profit on ordinary activities for the year was £24.8m (2008  £50.5m). ….During the year the company disposed of its investments in BDD Holding A/S and Invest World A/S, two companies in Denmark, which closed during the year.  The company recognised a loss on disposal of these investments of £11.9m).”

I am trying to determine whether the loss of £11.9m relates to Betfair’s acquisition of Pokerchamps.

Betfair Australasia Pty Ltd had, according to Reuters, recorded a net loss of around A$11.8 million for the year to the end of April 2009.  Betfair’s marketing costs had allegedly increased to A$7.7 million for the year, up from A$1.3 million, “following the lifting of bans on interstate advertising”.

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The relationship between William Hill and the betting exchanges has not been a good one. On January 29, 2003, David Harding on the subject of Betfair’s impact on the the over-round said; “Some racecourse markets now return overrounds of only 1.2 to 1.3 per cent per runner. That is not sustainable. I cannot have a price mechanism for 50% of my business being desecrated.

In a recent interview with Betview magazine Ralph Topping, Hills’ current head had this to say of Betfair;

“‘I call Betfair the choirboys of the betting industry – “look at us we’re so innocent” – actually the exchanges are the biggest Masonic lodge there is.   They’re a massive secret society where illegal gambling is taking place. What would throw a spanner in the works is if William Hill came up with an exchange model which could be offered in our betting shops or through our telephone business.”

A fascinating portrayal of one of the most transparent betting companies in the world.

EDITOR’S NOTE: BetFair’s Mark Davies has his own take on the Topping statement.

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Credit cards Mastercard and Visa have recently imposed restrictions on online gambling transactions to US customers, in preparation for the implementation of the anti-gambling legislation in June this year.

The following was reported by eGaming Review:

Mastercard crackdown leaves US players unable to pay

US-facing operators have been hit by an overnight crackdown on online gambling payments by credit card giant Mastercard. The US company is believed to have toughened its stance on the widespread practice of operators coding egaming transaction as other kinds of online commerce, which will all (sic) its US customers from using their cards to gamble online.

Rival US card giant Visa is rumoured to have taken a similar measure, although this could not be confirmed at the time of writing.

The action is a sign that banks and payment companies are preparing for implementation of America’s Unlawful Internet Gambling Enforcement Act (UIGEA), which bans the facilitation of online gambling by payment companies. This was originally supposed to have been enforced from 1 December 2009, although the US treasury later approved a delay allowing companies until 1 June 2009 to comply…(more)

In the followup article, it was established that Visa was also implementing the restriction on US customers:

Visa declining US egaming payments

The crackdown on US online gambling credit card payments that began on Wednesday is being operated by Visa as well as rival US credit card giant Mastercard, EGRmagazine has now confirmed, with tens of thousands of US online gamblers likely to have been affected.

As reported yesterday, US-facing operators were hit by an overnight tightening of restrictions on the use of credit cards for egaming transaction ahead of the implementation of America’s Unlawful Internet Gambling Enforcement Act (UIGEA) law on 1 June, which bans the facilitation of online gambling by banks and other payment companies.

The action was at the time of writing confirmed as applying to US-registered cards issued by Mastercard, but rumours that a crackdown had also been launched by Visa had not been substantiated. However eGaming Review has now confirmed that these too are subject to the ban. Repeated attempts to use a US-registered Visa card by an eGaming Review reporter on PokerStars last night were declined, with the American poker giant sending an email in response that read:

“Status: DECLINED.

Your credit card transaction has been declined. If your credit card information was entered correctly and you have sufficient funds, your transaction was probably declined due to Internet gaming restrictions set by your credit card issuer…” (more)

So:

In order to better avoid of the USA anti-gambling radar, some gambling operators accepting US customers have been coding their Visa and Mastercard transactions in a manner as to not appear as gambling-related. The correct “internet gambing” merchant code is 7995; some operators have been putting their transactions through thus, and taking a chance as to whether or not the deposit goes through; others have not.

To put it another way: they’ve been trying to cheat the system.

Since the February crackdown appears to have been applied retrospectively to January, players now face the prospect that their deposits – with which they will have had plenty of time to play, and lose or win on accordingly – will now almost certainly not be honoured by Mastercard and Visa, resulting in an effective chargeback. This may have a knock-on effect when it comes to winning players receiving their payments.

And while the general tone of the internet discussion on this matter has been one of condemnation of the US administration in the wielding of its prohibitionist axe, I would personally like to ask this question: why should we not lay the blame for this squarely at the door of the online gambling operators, still dealing to US customers, who tried to cheat the system in the first place?

Their motives were purely profit-driven in attempting to stay below the radar. But it is the players, who committed no wrongdoing, who may suffer as a consequence.

It is of course also the case that not all operators have been trying to cheat the system. Some, such as Pokerstars, have been coding their transactions upfront as “internet gambling”; in fact, in another EGR article they made a point of distancing themselves from the practice:

PokerStars does not, nor ever has engaged in the practices of mis-coded credit card transactions. We have therefore been unaffected by any crackdown by Visa or MasterCard to close down such mis-coded processing accounts.

So, all well and good for the folks who’ve behaved honestly.

But the casinos and sportsbooks that have been trying to put one over Mastercard and Visa, whatever the ultimate cost they pay as a result of this matter may be, do not deserve any sympathy.

They particularly do not deserve any sympathy from those players who may end up seriously inconvenienced, and possibly out of pocket, as a result of their duplicity.

There’s been, predictably enough, quite a lot of discussion of this move that has such potential sweeping effects on the industry: see the No more Mastercard article at Bookmakers Review, and the Mastercard blocks US poker discussion at 2+2 Poker (“Intentionally mis-coding a CC transaction is a crime in many places around the globe.” – I quite agree); also my own Mastercard and Visa online gambling crackdown article, and one tiny piece of mainstream media coverage, the Timesonline online gambling comment – actually, quite funny, so I’ll quote it:

Operators including PokerStars which continue to defy the US ban have been hit by a crackdown on internet gambling payments by Mastercard and Visa, the credit card companies.

Great. The one piece of mainstream media coverage gets it completely wrong.

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“Not inflation”, the gold critics will shout, in one of their go-to arguments. This is what we hear from CNBC’s Mark Haines at every possible chance: since 1980, gold has not kept up with the CPI and so shouldn’t be used as an inflation hedge. One would point out to Mark that this is analogous to arguing for global cooling based on that one 2005 start date. If you pick basically any other start date but the one corresponding to gold’s 1980 peak, you see something different, even giving CPI a long head start over floating gold prices:

But in shorter time-frames gold critics do have half a point. Since 2003, on a daily basis, gold returns have only been 12.5% correlated to changes in the inflation rate implied by 10-year TIPs. On a monthly basis, gold returns are 9% correlated to those of the TIPs spread.

We can look back further if we examine the the monthly performance of gold versus year-over-year changes in the CPI index. The CPI index for a given month is released in the subsequent month, so CPI monthly values are shifted forward in this study to correspond to the month of their release. The YoY change in CPI is further assumed to be the market’s expectation of future inflation. All gold prices here are daily averages based on the London PM fix through December 1974, and Comex/CME spot thereafter.

Ignoring the fact that gold generally rose in this period, it doesn’t do particularly well when inflation is elevated by this definition. A cut-off of 4% was used because it was the round number that most nearly bisected the 501 months in question, but the pattern holds-up when this parameter and other assumptions are varied:

So what does gold hedge against? Gold does well when real returns are low. You can’t consider inflation without looking at prevailing rates and growth. The rates used below are the average of daily 10yr constant maturity rates (GS10) within a given month. As Larry David would say, “pretty … pretty good”:

3% was used because it is again the round number that most nearly bisects the observations, but it can be varied without changing the essential result. There are also simple ways to define low real returns without a fixed parameter that show similar performance breakdowns with very different distributions of months. Now, these are retrospective studies, not trading systems, but obviously there is little chance that those returns were drawn from populations with the same mean.

It’s surprising that thoughtful types like Nouriel Roubini and Martin Feldstein have questioned gold’s inflation hedging, but didn’t mention this point — it seems glaring: people hold the relatively useless metal when real rates and opportunity cost are low. This simple point somehow never comes through in the noise surrounding gold: the glib Spam-sagacity vs. the Fall of The Republic, all the go-to arguments.

Clearly there are other factors that may throw the model off for long stretches of time. These may be false positives (e.g. non-dollar weakness) or false negatives (e.g. if gold is monetized to the point that it rises in deflation).

Putting aside the current weakness related to the Euro and elevating risk aversion, since I’m expecting real rates to be on the low end compared to the late 20th century, my bias is still long gold. If yields should rise, especially if they are driven by vigilance, gold might make less sense.

[Cross-posted with minor changes from Seeking Alpha]

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As somebody who likes to “back and lay” on UK horse racing, I was more than annoyed, when having placed a bet on a UK horse race, Betfair’s software malfunctioned, meaning that I was unable to lay off my bet as was my intention.

To those of us that engage in backing and laying, the result of the race is irrelevant; we are trading on price movements and price movements alone.  It was my belief (mistaken) that the contract that I had entered into with Betfair, would ensure that at all times Betfair would provide me with the means to back and lay, and that where it was unable to do so, the company would rule that as a proper market had not been formed on the race, my bet would be declared void, and my stake monies would be returned.

Alas, this was not so, as the following reply from Betfair makes clear;

“As the site was not available to any customers between 2 – 4pm, no bets were placed during this time and as this was due to matters beyond our control, our terms and conditions (11.3) state that:

We are not liable for the failure of any equipment or software howsoever caused, wherever located or administered, or whether under our direct control or not, that may prevent the operation of our betting services, impede the placing of orders for bets or the matching of bets, or prevent you from being able to contact us. In particular you should be aware that if you place a bet with the intention of subsequently placing a separate bet to reduce the liability incurred by the initial bet, there can never be a guarantee that the Exchange will be available at the point you wish to place the subsequent bet.”

As it happens, the race concerned was the 2.45 at Fontwell, which somewhat contradicts Betfair’s statement that; “As the site was not available to any customers between 2 – 4pm, no bets were placed during this time.”

That aside it would seem that I have been snared by Betfair’s all encompassing exclusion clause, to the effect that;

“In particular you should be aware that if you place a bet with the intention of subsequently placing a separate bet to reduce the liability incurred by the initial bet, there can never be a guarantee that the Exchange will be available at the point you wish to place the subsequent bet.”

I do not accept that this exclusion clause is fair or equitable, and accordingly I shall seek legal advice as to its efficacy.  In the meantime, I will no longer use my Betfair account.

Betfair are rumoured to be lining up for a 1.5bn flotation; it is a disgrace that they do not have back up servers to prevent their site from crashing.  When such an occurrence does take place, it is in Betfair’s interest to return all bets.  Betfair, the revolutionary betting company, have much to learn about the concept of goodwill.

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Ladbrokes suffered a mighty embarrassment, earlier this week, and 4,500,000 customers had cause to get nervous, when the Mail On Sunday revealed that the UK uber-bookmaker’s customer database had been offered to them for sale:

For sale: Personal details of millions of Ladbrokes gamblers, offered to the MoS by a mysterious Australian

The confidential records of millions of British gamblers who bet with top bookmaker Ladbrokes have been offered for sale to the Mail On Sunday. The huge data theft is now at the centre of a criminal investigation after this newspaper was given the personal information of 10,000 Ladbrokes customers and offered access to its database of 4.5 million people in the UK and abroad.

(more…)

This is no fake claim, as attested to by the fact that a “taster” of the full database was handed over by the culprit, fully ten thousand names and highly confidential personal details for the purpose of whetting the potential client’s appetite.

Hey-ho. The gambling industry at its predictable worst.

These incidents are not new – I reported on an occurrence a few years ago in which an online gambling industry leader touted a database of 100,000 UK players to the highest bidder on his forum. Neither are they remotely hard to believe; while the average customer service representative might struggle to access his company’s full customer list, an employee higher up the chain in the IT department should have no such difficulty – a quick copy, paste and save…and it’s time to start lining up the buyers. I daresay the names of four and a half million bona fide gamblers would fetch a very fine price.

And while our data watchdog, the ICO, huffs and puffs its righteous indignation, I’m sure they know there really is very, very little you can realistically do about this. Just one employee with access is all you need.

It serves as a reality check: when you put your details online, they are just that: online. Assume that, at some future point, someone will be hawking your phone number, email and physical address to the highest bidder.

I commented also in my Ladbrokes data theft post, and see also the Racing Post’s Ladbrokes reassure users over data protection article.

Oh well, I don’t know; maybe privacy is overrated.

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Just bought Wall Street Rolling at 10287; will close position just before the close of business on X-Mas Eve – confidently banking profit.

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