Tippett on Speed

Although I knew Tom Tippett had some good research on his site I didn't know until today that he did a bit of analysis on the baserunning question I wrote about the other day. In his article Measuring the Impact of Speed he says the following regarding Ichiro Suzuki's 2001 season:

"The most surprising thing about this type of analysis is the relatively small number of baserunning opportunities we end up with. Players only reach base so many times in a season, and after you subtract the times when (a) the inning ends without any more hits, (b) they can jog home on a double, triple or homerun, and (c) they are blocked by another runner, players rarely get more than 50 opportunities per season to take an extra base on a hit.

Last year, Ichiro had 45 such opportunities, and he took 6 more bases than the average runner. He wasn't once thrown out trying in those situations. Six extra bases may not seem like a lot, but it was enough to qualify for our top baserunning rating."

That matches up very well with what I found. Of course, in my analysis runners get more opportunities because I don't take into account the runners in front of them and do give them credit for bases that they "should" get. So in 2003 Ichiro had 84 opportunities and was expected to garner 121.74 bases. He actually advanced 125 bases for an IBP of 1.03 and an IR of 1.08.

Tom also goes on to talk about other kinds of advancements and all the ways in which runners might be credited with extra bases. In Ichiro's case he finds that he took 30 extra bases which might equate to 6-12 extra runs using measures that are not normally accounted for.