First of all, my excuses that this response will probably rather late, but that's simply because I'm still a member with rather few posts and thus they all have to be checked by a mod or admin or something... so ye, little delay there.
How are you coming up with these numbers?
The numbers simply come from Parquet Posse's post which states that
a) The white sox runline is +175 with an Accuscore-percentage of 46.7%
b) The Giants runline is +144 with an Accuscore-percentage of 52.4%
Now, how I got the line-to-percentage numbers is simply that you are laying a specific amount to win "a specific amount + your wager". So, a toss-up would be even money if we assume the bookmaker takes no juice and since I just wrote the formula be "Wager / (Profit + Wager)" = % this easy example would be (with an $100 wager) 100/200 = 0.5 = 50% which would be the percentage.
If you are betting a favorite of for instance -140 the Wager would be 140 to Win 100. Since you as well 'win' your wager back it would be 140 / (100+140) = 0.58333 and thus for the bet to be profitable you will need a certainty of winning the bet of 58.3%
If you are betting a dog of for instance +125 the Wager would be 100 to win 125. Since you would again 'win' the wager back it would be 100 / (125+100) = 0.444 and thus you would need at least a certainty of 44.4% of winning the bet.
Since Accuscore gives the percentages how certain they are of plays, all that is left is to calculate the difference between their percentage and the "Wager / (Profit + wager)". This difference can either be calculated by substracting the percentages (as I did in my previous post with for instance 52.4 - 41 = 11.4) to see the percentage-difference
or by deviding them on each other (as I did in my first post in this thread) -- both methods are equal and merely a matter of taste... even though the substracting might look easier to the eye.