For most of baseball history, baserunning has been measured by stolen bases and caught stealing. Fans and analysts have complained for a long time that there is more to baserunning than stealing bases and that the impact of baserunning has not been measured adequately. For example, a good baserunner will go from first to third on a single or advance from second to third on a fly ball more often than a poor baserunner.
With the development of play-by-play databases such as Retrosheet, it is now possible to measure baserunning beyond stolen bases. The most advanced baserunning metric is Equivalent Baserunning Runs (EQBRR) found at at Baseball Prospectus. Developed by former Baseball Prospectus writer and current MLB team statistician Dan Fox, EQBRR takes into account the following types of baserunner advancement:
(1) Ground outs (e.g. Runner is on first base with other bases unoccupied and less than two outs and then advances to second on a ground out)
(2) Air outs (e.g. Runner is on second base with third base unoccupied and less than two outs and then advances to third on a fly out)
(3) Stolen bases, caught stealing and pickoffs.
(4) Hits (Runner goes from first to third on a single, second to home on a single or first to home on a double)
(5) Other (passed balls, wild pitches, balks)
A complex algorithm takes all of the above into consideration in estimating the number of runs which a player contributed to his team above what you would expect from an average baserunner. For those who are interested in the details, the methodology can be found here, here and here.
The top baserunners in the American League according to EQBRR in 2010 are listed below:
Chone Figgins, Sea 5.9
Elvis Andrus, Tex 5.9
Carl Crawford, TB 5.4
Ben Zobrist, TB 3.6
Brett Gardner, NYA 3.6
Austin Jackson, Det 2.8
Austin Jackson is sixth in the league with an EQBRR of 2.8. This means that he has contributed an estimated 2.8 runs above what the average baserunner would have contributed given the same opportunities. A player's baserunning contribution is generally a lot less than his hitting contribution but some players actually do make a significant impact with their baserunning and it should be considered in determining their overall offensive value.
The EQBRRs for all Tigers with 100 or more opportunities for base advancement are listed below:
Austin Jackson +2.8
Johnny Damon +2.0
Magglio Ordonez +1.2
Gerald Laird +0.2
Ramon Santiago -0.4
Brandon Inge -0.6
Brennan Boesch -1.2
Miguel Cabrera -1.6
Carlos Guillen -1.7
The biggest surprise on the list might be Ordonez at +1.2. Magglio is not known for his speed on the bases. This result is probably just a fluke as he is usually below average on this statistic.
As a team, the Tigers rank third in the league:
Tampa Bay 6.6
Which team is last in the league? Mike Scioscia's aggressive Angels are 12.4 runs below average. That just goes to show that aggressive baserunning only works when you've got runners who have the ability to execute.