09-30-2009, 09:29 AM
The plus minus stat is the way the Fielding Bible measures defense. It's based off of a zone that a particular player plays in and if they should be able to field it. Here's a quick summary here.
http://www.fieldingbible.com/
<!--quoteo-->QUOTE <!--quotec-->John Dewan
My book, The Fielding Bible, goes into great length (ad nauseum to some) describing the new fielding system we developed at Baseball Info Solutions, the Plus/Minus System. Video Scouts at BIS review video of every play of every major league game and record detailed information on each play, such as the location of each batted ball, the speed, the type of hit, etc. Using this in-depth data, we’re able to figure out how each player compares to his peers at his position. How often does Derek Jeter field that softly batted ball located 20 feet to the right of the normal shortstop position, for example, compared to all other major league shortstops?
A player gets credit (a "plus" number) if he makes a play that at least one other player at his position missed during the season, and he loses credit (a "minus" number) if he misses a play that at least one player made. The size of the credit is directly related to how often players make the play. Each play is looked at individually, and a score is given for each play. Sum up all the plays for each player at his position and you get his total plus/minus for the season. A total plus/minus score near zero means the player is average. A score above zero is above average and a negative score is below average. Adam Everett turned in the highest score we’ve had in four years of using the system with a +43 at shortstop in 2006. That means he made 43 more plays than the average MLB shortstop would make.<!--QuoteEnd--><!--QuoteEEnd-->
Now, it like many defensive measurements, is by no means perfect. For instance, this measurement is basically worthless for 1B because it doesn't measure some of the key attributes that makes a 1B a good defender. But, I feel it is fairly accurate when measuring outfielders.
The minus 24 for Rowand means that he's a below average centerfielder and has had a lot of opportunities to prove his worth over the last couple of years because he's an everyday centerfielder. It doesn't necessarily mean he's the 4th worst centerfielder in MLB right now. He's fairly close and I would say he's one of the worst everyday centerfielders.
http://www.fieldingbible.com/
<!--quoteo-->QUOTE <!--quotec-->John Dewan
My book, The Fielding Bible, goes into great length (ad nauseum to some) describing the new fielding system we developed at Baseball Info Solutions, the Plus/Minus System. Video Scouts at BIS review video of every play of every major league game and record detailed information on each play, such as the location of each batted ball, the speed, the type of hit, etc. Using this in-depth data, we’re able to figure out how each player compares to his peers at his position. How often does Derek Jeter field that softly batted ball located 20 feet to the right of the normal shortstop position, for example, compared to all other major league shortstops?
A player gets credit (a "plus" number) if he makes a play that at least one other player at his position missed during the season, and he loses credit (a "minus" number) if he misses a play that at least one player made. The size of the credit is directly related to how often players make the play. Each play is looked at individually, and a score is given for each play. Sum up all the plays for each player at his position and you get his total plus/minus for the season. A total plus/minus score near zero means the player is average. A score above zero is above average and a negative score is below average. Adam Everett turned in the highest score we’ve had in four years of using the system with a +43 at shortstop in 2006. That means he made 43 more plays than the average MLB shortstop would make.<!--QuoteEnd--><!--QuoteEEnd-->
Now, it like many defensive measurements, is by no means perfect. For instance, this measurement is basically worthless for 1B because it doesn't measure some of the key attributes that makes a 1B a good defender. But, I feel it is fairly accurate when measuring outfielders.
The minus 24 for Rowand means that he's a below average centerfielder and has had a lot of opportunities to prove his worth over the last couple of years because he's an everyday centerfielder. It doesn't necessarily mean he's the 4th worst centerfielder in MLB right now. He's fairly close and I would say he's one of the worst everyday centerfielders.