The laptop that I use for my research projects is still down, so instead I am highlighting the work of someone else on this blog. Dave Clark of Sounder at Heart has been doing some work with the proprietor of the Behind the Net hockey website, which is a rich compendium of hockey statistical analysis. I have to say that it's everything I want my site to be when it grows up and jumps off the ivory tower (haha!).
Between the two of them, they have compiled scoring and shot-making statistics for MLS players during this season, and used those data to calculate plus/minus ratings in goals and shots. You can find the data tables here, and the table can be sorted on clickable columns. Here is an explanation of the columns, thanks to Dave:
GP = Games Played
Mins = Minutes
SF = Shots For (credit for every shot your team takes while you are on the pitch)
SA = Shots Against
GF = Goals For
GA = Goals Against
SPCTF = Shooting Percentage For
SPCTA = Shooting Percentage Against
PDO = = 100 would mean that player shooting % F/A is at exactly league average. At the team level PDO can indicate a team that is underperforming (<100) or overperforming (>100). At the player level more variation is expected, but significant space either way means a player is likely to regress to mean.
SDIFF/90 = is Shots +/- for every 90 minutes
GDIFF/90 = same for goals
I have my disagreements with the use of plus/minus ratings from hockey in that it is difficult to deal with situations where a player has been ejected from a match resulting in a numerical disadvantage. I'm approaching the problem from the example of basketball, but the downside of that approach is that it requires play-by-play data — which in soccer's case is actually easier to get (lineup information, substitute information, and goals and ejections) but just as challenging to compile into a usable format.
At any rate, the data in the table will be more than enough to keep stats geeks engaged for a long time. Click through to the link and find out what you think.