I think one of the hardest things to do as a punter is knowing whether you have an edge in a market and whether the bets you place do in fact have positive expected value (+EV). +EV just means that we would expect a positive return from each bet placed (i.e. value).
Simply put your profit and loss on a market is a very crude and I feel pretty unsatisfactory measure of potential future outcomes. Variance (different tweet) is a very real problem and it is tough to know whether you are being lucky/unlucky or running as expected.
One of the few measures we do have is something called the Closing Line Value (CLV) and is again something for another tweet. However, in essence it is assuming that the final market prices are accurate and it is whether you took better or worse prices than that closing price.
Whilst not perfect it does give a good insight into whether you are potentially getting value and is measurable. I have found it is more suited though to those sports where you have two or three outcomes on an event. (i.e. Football, US Sports, Cricket, etc)
I remain to be convinced it is as good a metric for a sport like golf or markets where liquidity is low. The problem with golf is the tipsters and the undue influence that they have on the markets. Lets say @BenColey tips up a player at 50/1. Imagine that 500 people have even just £10 on that player. Suddenly you have £250k liability on that runner across the market. Yes that maybe spread across bookmakers and exchanges but it is also just one source of bets and ends up distorting the market. Yes the layers can step in and take it on. They have limits though. Not many will want a completely lopsided book just because a player has been tipped up. Particularly when some shrewd judges clearly like the players chances. So how do you measure if you have +EV bets. Its really difficult.
I think you can get an idea by how the bet performs relative to your expectations. If that sort of bet regularly trades at much shorter prices then there is a fair chance it was value. More than that though is to look at the performance in more detail.
Was the player suited by the course as expected, was their play as expected, was there a weather bias, did someone else just putt lights out, were they unlucky, etc etc. It depends on what you valued as super important and why you had the bet in the first place.
You have to be wary though as it can again be misleading in that you may just be lucky or unlucky with what is happening. You do have problems with sample sizes especially in something like golf where you have bigger prices. You will get a feel for it though.
There is no magic solution as to whether you are getting +EV. You can use P/L, CLV or any other metric you like. Nothing is perfect though. All have flaws. You have to trust your gut instinct a bit and be honest as to whether you keep getting it in, in favourable positions.
ProPunting 