Longshot Bias
First of all I had better explain my self for my lack of posts recently; unfortunately my Internet company decided to cancel our subscription because we upgraded our TV subscription with them, and it will take another week to sort out! I can’t believe it! (did anyone else read that last bit in a Victor Meldrew voice?)
Now I should start with my next apology- an apology for the gloating I am about to impart; who won the Shanghai masters? Novak Djokovic! now I guess you could say that I backed Murray, but I also said spread your bets and include the young serb in those bets. If you listened to me you would be in the reddies right now, but if your anything like me, you probably didn’t bet on it because other things came up- bloody Internet. Before you say anything, I don’t have the time to go to the bookies, and it’s too far
Anyway, as the title suggests I wanted to touch on a theory (don’t worry I wont make it as confusing as some of the texts I read to write this post!) called long shot bias, now this is a theory that bettors over value some bets, and under value others.
For example, on skybet, Chelsea this weekend are favourites against Newcastle at 1/5 (1.2), Newcastle are valued at 14/1 (15), now that sounds worth a punt! With a draw at 5/1 you can see from the probability page that the total probability is 106.67%. Now as long as betting is made as to the true reflection of the value of the bets, the bookmakers will make a small profit (he laughs). However, due to the Risk loving bettors seeing the 14/1 shot and thinking that they can make a lot of money, and quickly, it doesn’t quite work out to the Economist rule.
With these odds, bookmakers expect bettors to gamble £15 on Chelsea to win for every £1.20 placed on Newcastle. However, this is relying on bettors conforming to economic efficiency; which we know to be very untrue. Therefore the odds of the game will change due to the likely hood of each outcome being undervalued or overvalued. So if on average there is £4 being bet on Newcastle for every £15 on Chelsea, the bookmakers may change the odds of each team to get gambling trends towards their targets, and as a result they will make as much as they can. It’s easy to see why they do this, as if for some unknown reason, no one backed Chelsea, and £15 was placed on Newcastle to win, and Newcastle did win, the bookmakers would be out of pocket by £210, and they can’t let that happen as the house always wins!
So the theory is quite simple and the proof is pretty damning, thanks to the progambler for bringing the findings of William Hill to my attention; in their studies they prove that Long shot Bias is a reality as people overvalue or undervalue bets, now this is apparent as more money has been lost by gamblers than should have been.
As you can see from the chart, backing every home and away result would have returned on average a loss of 12.44 pence for every £1 staked. By contrast, backing all home and away prices greater than 2/1 would have lost the punter 16.75 pence for every £1 staked. Betting on all teams with an odds-on price would have lost 9.17 pence. Backing teams at shorter than 1/2 would have lost 4.86 pence for every £1. Now this doesn’t reflect well on gambling, it doesn’t appear there is anyway of winning!
However, there is research proving that in some circumstances that although Longshot Bias is very apparent in the gambling market, Longshot Bias can be mitigated in some circumstances. Paton and Vaughan Williams (1998) research explains that due to the nature of high profile events, such as some Tennis Grand Slams that there is a negative Longshot Bias; they explain that due to the importance, length of game, players experience and the ability to question the umpire, that as long as there is no mitigating circumstances, the favourite is more likely to win. As a result, whether it’s due to sentiment, a lack of clear favourite, or even bragging rights there can be negative Longshot bias where the favourite is backed more than they should be.
Now, I know this post was a bit of a lesson, but I hope you learned a few things; principally that if you bet on the favourite more than on the Longshot you will win more often and lose less, it’s up to you if you can make a profit from it. Take it from me, if you take the stance of a Negative Longshot bias as I do, you can make money from it (I’m up to £240 from my initial £5 investment so far
)
Happy days!

