I have not heard back from the fellow that originated this
approach to handicapping MLB money lines. Therefore, I can’t verify that my
program code replicates his Excel approach perfectly. I decided to move forward
and make a couple of modifications to his approach and back test again.
The first is the manor of expressing the ML odds. He
subtracted 100 from to ML’s to eliminate the gap between -100 and +100, then
did linear regression. This is a technique I hadn’t seen before, so I elected
to convert the ML’s from the American style to the European style and do the
regression. Converting these does make the favorite odds non-linear, but it is
a more traditional approach.
Te second change dealt with how to combine each team’s
expected win probabilities into a normalize form (adding up to 1.00). I couldn’t
quite figure out how he did this, and he didn’t venture an explanation when
asked. I elected to again go a more traditional route and use Bill James’ Log5
technique.
Following are the results when I made both changes and
included 2018 data to the All-Star break.
|
Eur and Log5
|
Number
|
Amt Bet
|
Net
|
Actual Ret/$
|
|
2010
|
1,960
|
$246,779
|
-$2,651
|
$0.989
|
|
2011
|
1,963
|
$239,981
|
-$3,934
|
$0.984
|
|
2012
|
1,971
|
$242,239
|
-$3,164
|
$0.987
|
|
2013
|
1,971
|
$249,978
|
-$9,798
|
$0.961
|
|
2014
|
1,941
|
$231,529
|
-$8,865
|
$0.962
|
|
2015
|
1,949
|
$237,962
|
-$9,495
|
$0.960
|
|
2016
|
1,942
|
$239,530
|
-$21,387
|
$0.911
|
|
2017
|
1,945
|
$247,642
|
-$5,172
|
$0.979
|
|
2018
|
968
|
$122,265
|
-$134
|
$0.999
|
|
Total
|
16,610
|
$2,057,905
|
-$64,600
|
$0.969
|
The results appear to be almost random, no better than throwing
darts. That will terminate my look at this approach. This is the second system
that was described in the “Handicappers Think Tank” forum in www.sportsbookreview.com that I
decided to analyze. I probably won’t be chasing anymore of these unless I can
see some logic behind why it might work.
I probably will limit myself to systems I’ve developed in
future posts. Follow me on Twitter, @old44bill, to know when I post again.
