Out of Justin's "Conquering Risk" book (pg104):
"2. A team's offensive rating predicts how many points it will score (on average) against an average defense. This rating is measured by its average points scored per game in its first N games. You will call this P(off)."
Is this a fixed or rolling P(off) for the rest of the season? Say in round 5, we have an average of Team A's score for the first four rounds, which is 20. Is 20 then Team A's P(off) for the whole season?
Or do we calculate a rolling P(off) by averaging the four rounds previous to Round x?