when the 'proposition' ends up .5 the calculator is easy for me to understand. however when proposition ends up .0 i am confused of output to use. am i to use 'less than 12' or 'at most 12' for an under? do i factor in 'exactly 12'? keep in mind these are for bastardized NFL and NBA pricing so i'm not sure if that effects 'exactly 12'/push. there was no explanation in the provided example on the calculator page.
my second question is, when your poisson calc takes a number like 10.8 and rounds up to 11 for the proposition. do you compensate with your expected average?
Figure out the percentage of results over x.0, and under x.0. The ratio can be used to set a moneyline.
For example, if a result goes over 10.0 40%, under 30% (and lands on 10 30%) the price on the over should be (40/30) * -100, or -133. Under should be +133.
You should not have to round using a Poisson calculator. I'd be scared of rounding errors that big.