Truths, Lies and Tennis Statistics / Matthew Walton / 30 August 2007 / Leave a comment

"Magical" Matthew Walton considers why short-priced favourites sometimes don't become underdogs on Betfair till the bitter end

Try this exercise. Pick a match where you're not planning to have a bet before the action starts. You have an opinion, you know the players, but have no interest in getting involved in advance of the game beginning.

Then, follow the match as the play ebbs and flows and mark down the fluctuations on the exchanges. It really does provide a fascinating insight into the intelligence (or sometimes lack of it) that your fellow users display.

Such a study can teach you many things but here we will use it to highlight the often bewildering habit of people not seeing something that is right in front of their eyes. A refusal to acknowledge that barring a comeback more befitting of Lazarus, a match has only one logical conclusion.

The match we used was Max Mirnyi against Marcos Baghdatis in the first round at the US Open. Trading before the match had Mirnyi at around 8.00 and Baghdatis as a general 'shoo-in' at 1.12.

Now, in themselves, these prices were out of line to start with (Mirnyi had won their only previous meeting, this was his best Grand Slam venue, neither guy was in stellar form and the Russian is a talented, if serially under-achieving, player) but that's not the point to this debate.

Study the pattern of the markets in the list below (set number in brackets) :-

Pre-match: Baghdatis 1.12, Mirnyi 8.00

(1) Mirnyi breaks to lead 4-2 Baghdatis 1.50, Mirnyi 2.82
(1) Mirnyi takes first set Baghdatis 1.57, Mirnyi 2.70
(2) Baghdatis breaks to lead 3-1 Baghdatis 1.28, Mirnyi 4.40
(2) Mirnyi levels at 4-4 Baghdatis 1.63, Mirnyi 2.54
(2) Mirnyi wins second set Baghdatis 3.30, Mirnyi 1.41
(3) Baghdatis wins third set Baghdatis 1.89, Mirnyi 2.12
(4) Mirnyi serving 3-3, 15-40 Baghdatis 1.59, Mirnyi 2.54
(4) Mirnyi leads 6-5 Baghdatis 2.02, Mirnyi 1.96
(4) Baghdatis leads tie-break 5:1 Baghdatis 1.32, Mirnyi 4.10
(4) Baghdatis leads tie-break 6:5 Baghdatis 1.61, Mirnyi 2.30
(4) Mirnyi match point Baghdatis 3.50, Mirnyi 1.35 - wins!

There were only two points in the whole match where the Russian was the clear favourite - where he led by two sets to love and, somewhat unsurprisingly, when he held match point.

However, by watching the actual play you could see that Mirnyi was holding his own as he had a better win percentage on first serve and better stats on return. And it wasn't as if Baghdatis was squandering masses of break points (although in the whole match the Cypriot was 2/10 and Mirnyi was 3/7).

The simple fact of the matter is that even at the end of the third set, trailing by two sets to one, was Baghdatis the most likely winner? Or at 6-5 in the fourth, when Mirnyi had two bites at the cherry to win the set, and with it the match, he was only slightly prefered by the exchange users.

Most bizarre of all was twice at match point on the Baghdatis serve, the Russian was around 1.35. For sure, he wasn't 1.01 material but by the same token you'd have wanted more than 3.50 on Baghdatis to win from such a dire position.

This example suggests that punters are either pathologically averse to backing underdogs (they can only back favourites and always believe their man will come good in the end) or they pay no attention at all to the match as it is being played on the court or, most pertinent of all, they lose themselves in the match and don't sit back, take a considered view and weigh up the real value that's to be found in the match.

Do practice this approach. It's enlightening to see how other people react, and over-react, to the smallest of things. As a result, when you bet it can be done on a more rational and controlled basis, more with head and less with the heart.

Tags: Magical Matthew Walton, Marcos Baghdatis, Max Mirnyi, tennis trading