Joseph Buchdahl: The Analyst Who Proved You Can Beat Bookmakers With Pinnacle's Prices

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Most of the strategies on this site rest on one claim: that a sharp bookmaker’s prices, with the margin removed, are a good estimate of the true odds, and that you can profit by betting other bookmakers when they offer more. Joseph Buchdahl is one of the people who tested that claim most thoroughly, and published the results for anyone to check.

A data man

Buchdahl is a UK-based betting analyst who has worked with sports data and odds for around two decades. He runs Football-Data.co.uk and Tennis-Data.co.uk, which publish historical results and bookmaker odds used by countless bettors and researchers building their own models.

He has also written four books:

• Fixed Odds Sports Betting: Statistical Forecasting and Risk Management (2003)
• How to Find a Black Cat in a Coal Cellar: The Truth About Sports Tipsters (2012)
• Squares and Sharps, Suckers and Sharks: The Science, Psychology and Philosophy of Gambling
• Monte Carlo or Bust: Simple Simulations for Aspiring Sports Bettors

And he has written dozens of educational articles for Pinnacle’s betting resources site.

The wisdom of the crowd

Buchdahl’s best-known work is a method he calls the wisdom of the crowd. The idea is simple:

1. Take Pinnacle’s odds for a match.
2. Remove Pinnacle’s margin to get a fair probability for each outcome.
3. Compare those fair odds with prices at other bookmakers.
4. Bet whenever another bookmaker’s price is higher than the fair price by more than a set threshold.

That’s exactly the process our expected value calculator runs, and the one described in positive EV betting explained.

Removing the margin properly

Buchdahl paid close attention to how the margin is removed. Because of the favourite-longshot bias, bookmakers tend to put proportionally more margin on longshots. He tested several margin-removal models that account for this, including a method where the margin scales with the odds, an odds-ratio method, and a logarithmic method. Our devig guide covers why this matters.

What the data showed

In his updated 2017 analysis, Buchdahl examined 111,909 match odds from 37,303 European league games between July 2012 and May 2017. Two findings stood out:

• Returns followed expectations. As the value threshold rose, actual returns rose roughly in line with expected returns. At a 2% threshold, one model returned 5.71% against an expected 4.23%.
• Pinnacle was the most efficient. Its prices reflected true probabilities far better than those of several major UK bookmakers.

He has also reported testing the method going forward, posting value selections from 2015 onward and finding actual returns close to the predicted ones.

The returns were modest, a few percent, and needed thousands of bets to show up reliably. That’s the honest shape of +EV betting.

The catch: restrictions

Buchdahl has been open about the obvious problem. Bookmakers restrict customers who win this way. He has suggested keeping stakes small to stay under the radar for longer, and he’s been equally blunt about tipsters: his book on tipsters argues that genuine skill is rare and hard to tell apart from luck. Our account limits guide covers the legitimate ways to manage restrictions.

What you can borrow from Joseph Buchdahl

1. Use the sharpest price as your yardstick. You don’t need your own model to find value. See why Pinnacle’s line matters.
2. Remove the margin thoughtfully. Account for the favourite-longshot bias, especially when betting underdogs.
3. Test before you trust. Buchdahl backtested his method on tens of thousands of odds before recommending it. Track your own results the same way.
4. Expect small edges. A few percent per bet is a real, sustainable edge. Anything much larger deserves suspicion.
5. Be skeptical of tipsters. A short winning record usually says more about luck than skill.