I am using a SRS spreadsheet (Not necessary to know I believe, but it is as mentioned in this article) to determine team strength in various sports. This system allows me to predict an average score for both teams and what the variance of the score is for both teams.
I am running this in google sheets, and have been brute forcing the probability, by using a sheet with the sequence of numbers (0.0025, 0.005, 0.0075, 0.001 ... 0.9975) in the top row and first column and subtracting the distribution of one team from another for each cell.
The problem is this process results in over 150,000 formulas being updated at once every time an input into my formula is changed (i.e. Change one of the teams, the location of the game, etc.)
Is there a formula that can be used instead of attempting to brute force out a sample?
For example;
Team A has an average predicted score of 26.0 and a variance/standard deviation of 11.12
Team B has an average predicted score of 29.3 and a variance of 7.81
The random score is determined for each by using a CDF.
Is there a formula that can predict the odds of Team A having a better score than Team B assuming the random variables are independent?
For reference, my extent of knowledge is Calculus 1 (Specifically, taking AP Calculus in my senior year of high school)