Thursday, April 3, 2008

Quick Post About Strength of Schedule

Has anyone looked at Hollinger's Power Rankings?

Apparently Patrick was right in saying that Houston has had a tough schedule and Boston's schedule is a joke.

If you sort the teams by SOS (Strength of Schedule) you'll note that Boston has had the 4th easiest schedule (average win percentage of opponents was .490) and Houston has had THE HARDEST schedule (average win percentage of opponents was .516).

The only teams with an easier schedule than Boston are the Hawks, Knicks and Nets.

Jeez.

4 comments:

Patrick said...

I done told yall. Really, their injuries have affected them much more than their schedule though. Their record is really amazing considering what they've gone through. Still, I don't think they will make any noise this post season, but if they can stay healthy next season, watch out.

dullstone said...

I don't know, that stat kinda had the revese effect on me.

The easiest record is 1/100th away from being .500. The hardest is 1.6/100th way from being 500.

Seems closer than i would have thought--to think that all 30 teams fit within that .026 margin

jeremy said...

I'm no statistician but I'm pretty sure that the comparison to .500 is not as relevant as comparison to each other. Tom, you hit on exactly what I'm talking about when you say that the span from easiest to hardest is .026; it's within that realm that things should be compared.
You mentioned in one post recently that everyone loses a couple (or more) stupid games in a season. Going down that road, it's a given that ANY team will win 15 and lose 15. 80% of the league will win 25 and lose 25. That leaves only 30-40 games that really make the difference (also the same reason why the West looks so good to everyone and the best teams are only going to win 53-56 games). It's those games that matter. That said I think if you take the difference between any two teams' opponent winning percentage (ideally to another digit or two) and divide by the widest margin (actualy .027) then you get a percentage of difficulty difference (which is why we need more digits to accurately gauge).

Unfortunately that means that the hardest schedule is 100% more difficult than the easiset. There's probably a better way to do this but you get the point.

So the difference between the Rockets SOS (.508) and the Celtics SOS (.486) is .022 or 81.4% harder than the Celtics schedule was. To me, that percentage probably helps to define the difficulty of the determinent 40 games.

As a side note. If you want PROOF that the LEast is not even CLOSE to the BWest, notice that the SOSs are EXACTLY divided between conferences. The easiest 15 schedules were from the East and the hardest 15 were from the West.

jeremy said...

I could be slightly off with the math but I had to add another little note because I referenced this in another post and thought of another illustration to show how wide the gap actually is.

First let me say that .029 is 2.9%. I know its just semantics but, to me at least, .029 just sounds way smaller than 3% does.

Secondly, here's a breakdown of the actual games:

30 teams x 82 games each = 2460 games

A total opponent winning percentage of 50% [.500] would be 1230-1230

A total opponent winning percentage of 48.3% [.483] equates to an accumulative opponent record of close to: 1188-1272

A total opponent winning percentage of 51.2% [.512] equates to an accumulative opponent record of close to: 1260-1200

That's a 72 game difference.

Also note that the gap is now up to (and, now that the season is over, settled at) 2.9% so I guess it got wider over the last couple of weeks. As a Final(s?) little jab - Spurs ended with the most difficult SOS and BOS ended w/ the easiest SOS. Sounds like that super-scheduling computer did pretty well in divvying up opponents based on last season's results at least...