If you 're using a book such as Pinnacle, which deals dime run lines, then you'll typically see a reduction in vig when moving away from a money line between relatively evenly matched teams and an increase in vig when moving away from a money line with one team a relatively large favorite.
For example, look at tomorrow's Houston/Phillie game. Philly's a -111 to +103 favorite on the money line, for 1.833% vig. On the run line Philly's -169 to +159 for 1.415% vig.
Conversely, look at tomorrow's Tampa Bay at Minnesota game, where the Twins are -201 to +185 faves on the money line for 1.831% vig. and -1½ +101 faves to -111 on the run line for 2.304% vig.
Another issue is that run line dogs are offered at shorter odds than the same side on the money line, and run line faves at longer odds than the same side on the money line. Hence, from the perspective of
expected growth, were the +EV (same) sides of money lines and run lines sufficiently closely valued, there would then be incentive to both to betting the +1½ in preference to the money line, and to betting the money line in preference to the -1½.
Of course this latter argument will hold little weight for those that subscribe to the lottery mentality of sports betting, but for advantage bettors (whom we'd generally expect to avoid such ultimately detrimental staking strategies) it's clearly the superior option from the perspective of growth maximization and risk minimization.
Now this isn't to say that other factors won't be involved in determining whether to bet the money or the run line (factors such as those indicated by RickySteve and The HG), but rather that clearly lacking these other factors the decision can be made easier by the above.
So a couple of examples to summarize. All else being equal,
Florida -104 -1½ +155
Atlanta -104 +1½ -165
if you like Atlanta, then based on the above you should clearly go with the +1½ -165.
And all else being equal,
Washington +174 +1½ -120
N.Y. Mets -182 -1½ +110
if you like the Mets you should clearly go with the -182.
runlines
