from Amazon
Monday, August 25, 2008
Five of the ten best teams play in the AL east?
As AsrosFan is telling us:
I was just glancing at Andrew Dolphin’s ratings of MLB teams. I decided to go with the Predictive ranking.
Predictive Both schedule strength and rating vs. schedule strength are determined considering both the wins and losses and the score differentials. This rating contains none of the biases in the standard rating, but does weight recent games slightly more than past games since those are a better indication of the team’s current strength. This rating is the best of the first three for seeing how good teams are, and thus is the best for predicting future results.I could have used Improved RPI, but I wanted one that included run differential. Here are the rankings of all 30 teams: http://www.dolphinsim.com/ratings/mlb/index_pred.html
The first thing we notice is that the AL is ranked as having 10 out the top 11 teams. Mr. Dolphin’s analysis shows the AL as being much stronger, and thus teams with worse records than NL teams can actually be better due to strength of schedule. Indeed, looking at it from the expected losses standpoint, which Mr. Dolphin says “can be used to rank schedules”, the top 14 SOS are in the AL, meaning all the AL teams. And it’s not really close.
That would be astonishing enough, but this is what really caught my eye. Down further on the page, the rankings are split up by division. If we scroll to the AL East, we find these rankings: Boston: 1 Tampa Bay: 3 Toronto: 7 New York Yankees: 9 Baltimore: 10 . All five teams in the AL East are ranked in the top 10, that is, the top third of baseball. Baltimore, which at the time of the latest update, had a 61-66 record and RS/RA of 653/653, is ranked two spots ahead of Milwaukee, which had a 75-55 record and a RS/RA of 616/555.
To which I responded to the above and other questions in that thread:
When it comes to manipulating numbers in an intelligent manner, I’ll put Andy up against anyone.
I also have no insight into what Andy did, other than he does something similar for many sports. His site is blocked at the office, but from what I remember, it’s a standard “strength of schedule” adjustment, something more important in college ball than the pros.
The AL/NL difference between Orioles and Brewers makes sense. I use a standard +.025 wins per game for AL and -.025 wins for NL. That is, I consider the average AL team to be a true .525 team and the average NL team to be a true .475 team.
If the actual AL win% is .505 (because AL plays themselves so much more than they play NL), then you need to add +.020 wins per game for each AL team. And similarly, subtract .020 to each NL team. If you have some 125 games, that means you add about 2.5 wins or 25 runs differential to the AL team and subtract 25 runs to the NL team. So, a 50-run difference between an AL and NL team in NL team’s favor is really making the two teams equal.
Now, Andy did say he weights the more recent game a bit heavier (as he should, and that’s what the day-to-day Marcel does), then if the Orioles have been playing far better recently, then they’ll rank a bit higher than they normally would if you look at their season overall.
All that to say is that Andy’s got method behind his madness and deserves no outright dismissal. At the very least, it requires questioning even before skepticism.