One of the biggest mistakes that most sports bettors make is failure to shop for the best line and price.
Compare and think about the lines for a few minutes. How much are you betting per game? How many games do you bet (per day, per week, per year)? Most sports bettors throw hundreds or even thousands of dollars away each year because they do NOT line shop. This applies to losing sports bettors the same as it does to winners. Losing bettors end up losing considerably more than they should, while winning bettors do NOT win as much as they could.
While the ability to pick winners is nice, more often than NOT sports bettors are going off instinct and cannot win at a high enough amount to beat the vig. When shopping multiple betting sites for the best price, the effects of vig are nearly negated entirely.
Understanding Half Point Value
When shopping betting sites, both point spread and price are a concern. Deciding between +4 or +4.5, when both are equally priced, is a no brainer; we are going to take the extra half point. Where it becomes a challenge is when one site is offering +4.5 -110 and the other +4 -103. A professional sports bettor would head to his NBA database and calculate that over the past five years underdogs have lost by exactly 4 points 3.38% of the time. He might choose to refine that further, running only games where the spread was 3.5 to 5.5, or where the total predicted scores were similar, and then take weighted average.
To calculate which line is better, the first thing we need to know is how often we must win at -103 to break even. The math for that is risk divided by potential return. While we can solve this with simple algebra, the math is boring; so let’s just Google search “Moneyline Converter”. Using a moneyline/percentage calculator, plug in 52.43% to determine +4 -103 is the same as +4.5 -110. Therefore, while not by much, we are getting a little better expectation on +4.5 -110, so that is the line we will bet.
If you are betting professionally as a source of income, you will eventually want to get a database where you can calculate push rates on your own. For the casual bettor, here is some rough value of half points on and off of key numbers.
1=5.5 cents, 2=4 cents, 3=22 cents, 4=7.2 cents, 5=3.4 cents, 6=7 cents, 7=12 cents, 8=4.5 cents, 9=1.8 cents, 10=10.4 cents, 11=4.5 cents, 12=0.9 cents, 13=2.6 cents, 14=10.5 cents
To explain the above so it is clear, you will see 1 point is worth 5.5 cents. This means that +1.5 -110 is the same as +1 -104.5. Take another example, where 7 is worth 12 cents. This means +6.5 +100 is the same as +7 -112, and the same as +7.5 -124. As you can see in the second example, this can be used both ways. It also can be used on the favorite: -7.5 +100 is the same as -7 -112, which is the same as -6.5 -124. The push charts shared above are good enough for the casual gambler shopping lines.
Although, I say avoid buying points, there are exceptions.
Most online sports books offer players the opportunity to purchase half points at 10 cents each when the 3 or 7 is not involved. While this is generally a bad idea, looking at the push chart above you will find 10 and 14 are worth more than 10 cents. Therefore, after all your line shopping is done, if the bookmaker also sells half points at 10 cents, you should purchase them under the following circumstances:
1) +9.5 to +10 always purchase one or two half points to get the line to +10.5
2) -10.5 to -10 always purchase one or two half points to get the line to -9.5
3) +13.5 to +14 always purchase one or two half points to get the line to +14.5
4) -14.5 to -14 always purchase one or two half points to get the line to -13.5
Remember, in all the above examples, we are only buying these half points if they are sold at 10 cents each. These are probably the only half points you want to buy.