Two bloggers make points about leaving men on in last night's games. The Soxaholix is complaining about the Red Sox left leaving runners, including two innings in which Boston had the bases loaded with less than two out and didn't score. Was Watching exagerrates the number left on base (13 not 23) but his point is still well taken; the Yankees had a lot more opportunities than they converted.

Both approach the Left On Base stat as a bad thing. That's not really true. Leaving lots of men on base is often a sign of strong offense, one that puts lots of men on base! Here's the thirty teams this season, ranked by most left on base:

Last year, if you listened to Boston sports radio during the first half of the year, the question on everybody's mind was what good is all these people on base if you don't drive them in. Eventually, they come around to score, and that's what happened in the second half of last season. If you look at the chart above, you see that the Yankees and Red Sox, the two higest scoring teams in the majors, are near the top. They leave a lot of men on base because they put a lot of men on base and score a lot of runs. So if you're a Phillies fan, I'd be encouraged by this chart. Your team gets plenty of opportunities and with some luck those will turn into runs.

And just note that the Angels, who have left the fewest, also have not generated a lot of runs this season. They're not leaving a lot on simply because there's not a lot to leave on. Right now, I'd much rather have Oakland's offense than Los Angeles's; both are weak, but at least the Athletics have the opportunities to drive in runs.

Update: Bill Ferris writes:

I agree with your point that LOB isn't necessarily a bad thing and can be indicative of a good offense. However, I don't agree with the Oakland versus Anaheim conclusion at the end.

I believe it was Tom Tippett that came up with run efficiency average, which is the runs scored divided by (total bases+walks+hbp) as a measure of throughput. I atttached an excel sheet which has TBW, REA, and TBW/game. The Angels and A's are both at the bottom in terms of TBW/game, so neither offense is good. However, the Angels have been more efficient at getting those runners home, while the A's are down near the bottom again.

Also interesting to note is that the White Sox have been very efficient despite not having a particularly strong offense.

REA is measuring what has happened, not an ability. I believe the current lack of power on the Athletics is an anomaly. When the power returns to Chavez and Durazo, the men on base will start coming around to score.