Success of Closers

[hankp101]

Do any of the stats guys out there have any info on the success rate of teams with established closers in the 9th inning vs. those without established closers? I think it would be especially interesting to see if teams have gotten better at closing out games since this concept of 1 guy doing most of the closing came into vogue. That is, are teams better at closing out games now than they were before the closer became fashionable?

[CardsFanInChiTown]

What is your definition of an "established closer"?

[hankp101]

I suppose that is where we are in a grey area (think charcoal). I guess maybe the only way to find out would be to look at the trend in teams success at holding leads in the 9th over the last x number of years as closers have become more prevalent. The problem then becomes controlling for how good offenses were in a given year (roids era or no roids era), changing dimensions of ball parks, etc. I guess I have talked myself out of thinking this is even all that doable.