On Sundays, between 12 and 1 PM EST, I take a look at the SBR odds board to check where all the lines are heading. I am especially interested in the games I have already bet on because I want to check how good my line is against the closing line. A lot of bettors might know the feeling: you take a team at +3 on Tuesday, and by Sunday afternoon it’s suddenly +3.5. The negative shift makes me feel a little bit mad. But when I grab a -4 early and the line closes -5.5, it gives me a satisfying feeling. In this article, I want to explain how to calculate the closing line value.
The key to handicapping is pricing teams more accurately than the market over the long run. A spread on any given game says: this is the point where the market believes that 50% of possible outcomes fall on either side of the number. Our job as handicappers – no matter how we do it – is to find discrepancies between our estimate and the market’s estimate for a spread, total or whatever.
Let’s say the Miami Dolphins are favored by three points over the Raiders. If your handicapping process comes up with an estimated line of -6 in favor of the home team, your edge will be three points. You would think that the Dolphins win by 3 or more points in more than 50% of the possible outcomes. You apply a higher probability by your estimated line. That’s what handicapping is about. A very important aspect of sports betting, which goes hand in hand with pricing teams more accurately than the market, is beating the closing line. When bettors combine the latter with sound money management, they are on the right path.
Why beating the closing line is important
Sports betting is not about results; it’s about the process. You cannot control the outcome of games, but you can manage your handicapping/betting process. Our goal is to make +EV (plus expected value) decisions that lead to profitable outcomes long-term. The probabilities we apply in our handicapping process are estimated probabilities, we don’t know what the real chances for winning a particular bet are.
Beating the closing line means that you take a better number or price than what the market closes at, therefore holding a ticket with a higher probability of winning than if you made it at a later (or earlier) time. By beating the closing line, we add a share of possibility in our favor against the market. That’s why getting ahead of the closing line is such an integral part of betting. In theory, the closing lines represent the most efficient market conditions, because, at this point, all participants in the market had the best information available.
According to the efficient market hypothesis the closing odds are on average more accurate than the opening odds in predicting the probability of how a fixture will play out.
As Pinnacle explains in that article, opening lines, don’t reflect all the information available in the market, and therefore “inefficiencies exist”. As bettors, we want to bet into inefficient markets, to exploit discrepancies when we think our pricing is more accurate than the market. By beating the closing line consistently, you can prove that you do just that. Because Pinnacle is known as the sharpest bookmaker in the world, using their closing lines makes a lot of sense, because you expect their markets to be the most efficient when closing.
A consistent track record of beating the closing odds is, therefore, an indicator of consistent profits in the long run.
Calculation of Closing Line Value
But how to calculate how well you are beating the market? By tracking the closing line value (CLV). It is the difference in break-even percentage between the line you bet into and the closing line. Each price has a scientific break-even point (BEP). For +100 (2.00 in EU odds) it is 50%. You need to win 50% of your bets on prices of +100 to break even. For -120 it is 54.54%, you need to win 55 bets out of 100 to generate a profit. Here is how to calculate the break-even point:
Odds lower than EVEN: (1 / (odds / -100)) + 1
Odds higher than EVEN: (odds / 100) + 1
In an Excel spreadsheet, you type in the odds in one cell (A1) and another you type: =1/(IF(A1<0;1/(A1/-100)+1;A1/100+1))
In sports like Baseball or NHL, it’s relatively easy to calculate the closing line value. It’s simply the BEP from your line minus the BEP from the closing line. This gets divided by the original BEP. The last step is important because you want to measure the price difference relative to the original price. If you bet into -110 and the line closes -132, you will have managed a CLV of +8.63% ((56.90% – 52.38%) / 52.38%). But on the spread and total betting, it’s a little bit more complicated. The reason is that there aren’t just changes in the odds, but also for the lines.
Here comes the push probability into play. The push probability is the rate at which a certain spread pushes. For instance, 3 is the most common scoring margin in the NFL. The push frequency is around 9.6%, depending on which database you use. For instance, you bet into +3.5, and the line closes at +2.5. You would have added the whole push probability of the 3 to the range of your possible outcomes. At 3, the market would have bet into a line that pushes 9.6% of the time. When the line moves half a point, half the push frequency is applied.
You have two options: either you track the true closing price for the number you bet into, or you calculate an estimate. Now you could do a lot of work and calculate a lot of push frequencies. Or you are lazy and use a free calculator from the website SBRodds. Let’s say you bet into a favorite of -5 at -105 at Pinnacle and the line closes at -6.5 -110 with the dog closing at +6.5 +100. You type the closing line and prices into the tool:
Get the estimated closing price
Now the tool calculates the proper odds for the other lines around that number, based on the historical push probabilities. Because you bet into -5, you are interested in the current value of the -5 after the line moved to -6.5:
The current price of the -5 would be -132. This means you beat the closing line by 22 cents and managed to get a CLV of +8.6% – that’s it. In your spreadsheet, you type in your price and the closing price. You calculate both BEPs and subtract the second from the first, then divide it by the first BEP. The result is the closing line value. You are now able to track the closing line value of all your bets.
How to beat it
Beating the closing line requires handicapping skills and market knowledge. As I explained in the first paragraph, your goal is to price teams and totals more accurately than the market. By that, you can exploit an inefficiency in the markets. A big advantage is looking ahead. Before Sunday, take a look at the next week and handicap those games already. Make notes and write down which market reactions you expect depending on possible results during the current week. Try to anticipate where influential money will be going.
If you want to bet a line you expect money was coming in on, you grab the line as early as possible. You are prepared when the opening lines come out and have a much better market overview. Some services advertise things like sharp action reports to bait you to bet on so-called “steam moves.” But you want to bet those numbers as early as possible, not after the whole world recognizes the move. There lies the best closing line value.