how to calculated expected probability

[diggity.diggity]

Hi guys,
Say I think GsW have a 52% chance of winning hypothetical game outright.
How would I calculate the probability of them winning +2.5 and also does the formula change if it's -2.5?

[statnerds]

are you saying you are making your own number, but only for the ML? oh, so you are in need of a formula to assign values to each incremental point? I would actually suggest looking at the SBR push rate calculator.

[diggity.diggity]

are you saying you are making your own number, but only for the ML? oh, so you are in need of a formula to assign values to each incremental point? I would actually suggest looking at the SBR push rate calculator.

you got the idea what im trying to do correct.

im trying to come up with kelly bet sizing with what i think should be the true line as compare to the bookies.

i had a look at the calculator but im not sure if im doing it right.
for example in tonights game i assumed nyk should be +2.5 against the mavs
line was at +12 for the knicks putting the odds at -110 on both sides i got the probability of nyk covering +12 at 86.94% but thats way too high i think?