2008 MLB Iterative Power Rankings, Week 2

Base Runs is more predictive than either straight-up win% or Pyth%, yes. But like I said below, it's going to be a while before these ratings are truly meaningful, because the opponent adjustment is so dramatic when you've only played 10-12 games against 3-4 different opponents.

So Davis...what if we have a Patriots-esque scenario where a team is head and shoulders above its competition, but most of its competition (aka the AFC East) is poor by comparison...would that suggest the team isn't that good even though (as we find out) it was pretty damn good (disregarding the any given sunday scenario as seen w/ the giants) There isn't really a Division in baseball quite like that except maybe the AL central if the tigers keep sucking...

In football, it could definitely distort things because they play so few games against each unique opponent. But I think that over the course of a 162-game baseball season with inter-division and interleague play, you're going to see the effect be a lot smaller. Under this method, every team is connected to every other team via common opponents, so if you get enough unique opponents, it won't matter that you play in a weak division because you play many non-division teams who play other, different non-division teams themselves, and so on; the iterative process adjusts for the possibility of weak opponents dragging down your SOS.

IPR does have an SOS adjustment, that's where the iterations come in to play. Basically I calculate Base Runs scored/allowed for every team... Then I find their expected winning% from those Base Runs... Then I use the formula Power = (OppPower*RawBsW%)/((2*RawBsW%*OppPower)-OppPower-RawBsW%+1) to adjust for each team's SOS, and let the computer run 500 or so iterations, until the ratings no longer change. At that point, you have the IPR, which is adjusted for opponents, opponents' opponents, opponents' opponents' opponents, etc. As the number of unique opponents increases for each team, the schedule adjustment won't be so dramatic, and the ratings will be more stable (and more accurate). As far as novelty, it's kinda new, at least in this form... Baseball Prospectus uses a similar method, but as is the case with everything over there, it's proprietary. Conversely, the IPR is open-source -- you could recreate it yourself if you wanted. I do have to tip the hat to Doug Drinen for the idea, although his Simple Rating System is much more, well, simple than the IPR.

It's Saturday Alex....don't you have Formula 1 to watch or something?:) Alright I'll bite.....I will beat anyone here at algebra.

is math the same as mathematicses?

ugh Is maths the same as mathematicses

SS: No - it's every other week generally. JuT: Maths is our abbreviation of Mathematics.