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Statistical Baseball Betting System


Statistical Baseball Betting System

For the past couple of years I've wanted to come up with a statistical-based baseball betting system, but had never been able to do so under the belief that it was simply too difficult when compared to the other sports.

But one day it hit me that I was simply making it more difficult than it really needed to be and there was no reason why baseball should be treated differently than the other sports. A team's offense is constant, just as a football or basketball teams would be, the only difference is that a team's defense is largely determined by the starting pitcher, which does change on a daily basis, so we would have to have one offensive number and several defensive numbers, depending on the abilities of the pitchers involved.

Baseball is bet different than football or basketball, so those who are new to baseball betting should read How to Bet on Baseball and Understanding Money Lines before continuing.


When it comes to a baseball team's offense you can look at many stats, such as batting average, slugging percentage, on-base average, etc., but the one stat that is the most meaningful is simply runs scored. All of the other stats are basically just elements that go into a team's primary objective, which is to score runs.

For a team's offensive number, then, all we need are the number of runs it averages per game, which is pretty basic stuff.


Defense is a little trickier, as the number of runs a team is expected to allow will be largely determined by who is on the mound, so naturally we're going to have different defensive numbers for different starting pitchers. But the basic premise is the same, in that we can look a pitcher's strikeouts, walks and hits per nine innings, or any other stat, but the one that counts the most is simply runs allowed. Unfortunately, we can't rely on ERA, as it doesn't take into account unearned runs or the bullpen, but will have to calculate the number of runs the opposition scores against each starter.

(Those of you with the Stat Attack Baseball 2012 program can do it quickly and if you have the Gold or Platinum versions, you can use those throughout the year when it comes time to update your numbers.)

To get our defensive numbers, what we will do is take the average number of runs a pitcher's team allows when he's on the mound and divide that by the median number of runs scored by each team in his respective league. That might sound a bit complicated, but it will become pretty simple if you keep reading.

The Process in Steps

1. The first thing we will do is take all the American League teams and all the National League teams and calculate each team's average runs per game and secondly, calculate the median runs per team per league. With 14 AL teams, the median would simply be averaging the seventh and eighth highest-scoring teams. With 16 NL teams, it's averaging the eighth and ninth highest-scoring teams.

Because we're dealing with 14 and 16 teams, medians make a bit more sense than using average, as one or two teams could throw things out of sync. Since we already have calculated the averages for each team, we're not really adding much additional work, either.

2. Take the average number of runs a team allows with each pitcher and divide that by the offensive median of the league he pitches in. If the median number of runs scored per team is 4.1 and a pitcher allows 4.5 runs every time he takes the mound, the pitcher's rating is a 1.10. If our pitcher allows 3.6 runs per start, his number would be a .88, which is merely 3.6 divided by 4.1.

3. Multiply each team's offensive average by the opposing pitcher's rating to come up with the predicted number of runs for each team.

4. Subtract .07 cents from the road team and add .07 cents to the home team to account for home field advantage.

5. Take the team with the highest number of predicted runs and subtract the lower rated team's predicted runs. As each run is worth roughly 50 cents on the money line we will multiply that difference by .5 and to come up with our predicted line on the game.

Now, we'll jump to the next page and look at some examples and some basic rules.

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