Originally Posted by
HeeeHAWWWW
It's certainly important how much you beat/lost to the line by, because that's directly related to how much value you're getting (or not getting).
A lot of people just use a flat % approach - ie they beat the closer 53% of the time, or whatever. This is fairly useless, because it ignores the overall level of juice, and the degree to which the player beat the line.
Once you get sufficient sample size of your bets with the closers recorded, a more advanced test is to split your bets into bands relative to the closer, say into quintiles. So the bottom quintile, you sucked ass relative to the closer, perhaps it went 15% the wrong way. The 2nd quintile you did a bit better, hopefully nearer zero, etc etc, and by the top (5th) quintile you absolutely destroyed it. Calculate the RoI for each band, then correlate those RoIs against the medians of the bands. With a large enough number of bets, you can thus prove RoI correlates very precisely with how the line moved.