when it range, it pours
re the cost of dave eckstein’s poor range, a poster calling him/herself "anolis" asks an intelligent question:
"If I read this correctly, Eckstein made 44 less outs than might have been expected, and the analysis suggests that this translated into allowing 33 more runs that expected. Can this be correct? Since the outs that Eckstein missed almost surely turned into singles, is the expected value of turning an out into a single 3/4 of a run? Seems high to me."
yeah, me too — at first. the 33-run estimate comes from the chronicles of the lads, an anaheim angels blogger who is bravely/foolishly attempting to draw meaningful conclusions from defensive statistics. the chronicler explicitly posits that an out by a shortstop prevents 3/4 of a run — i quote:
"I turned to Chris Dial's methodology, in which a run value is assigned to each out a defender makes. For instance, 98.7% of outs made by a SS prevent a single. A single is worth .47 runs. Each out is also just that: an out, which has a value of roughly .28 runs. So, 98.7% of the outs made by a SS prevent .75 runs. (The other 1.3% account for 1.06 runs each, because sometimes those screamers by the SS get through the gap and go to wall for extra bases.)"
in other words, a routine 6-3 groundout moves an inning one out closer to completion (preventing .28 runs) and wipes out the run-scoring potential of a single (.47 runs); add .28 and .47, and you get .75. i hear those gears turning, anolis — now you want to know who the hell chris dial is and whether his methodology makes any sense — and unfortunately, i can’t answer either question. but here's the link if you want to check his math.
i can however apply some common sense, and the exercise encourages me that .75 runs per single is in fact a reasonable estimate. let’s begin with an easy case: bases loaded, two outs, grounder up the middle — shortstop comes up a step slow and the ball trickles through. the hit results in two runs — and potentially more, because the inning continues. every run that scores subsequently would/could have been prevented by a rangier shortstop, so the cost of that particular grounder is over 2.0 runs.
here’s another case: men on first and second, one out, groundball up the middle. if the ss fields it, it’s a double play and the inning is over; if the ball gets through, one run scores, a runner winds up at third with one out, and the batter’s on at first base — the runner at third will score about .75 of the time, and the runner at first will score a certain percentage of the time as well. add it all up and the failure to reach that hypothetical grounder costs, on average, right around 2.0 runs.
of course, there will also be hits that dribble through with two outs and none on, and no harm will come of them. but if you average out a small number of high-cost cases with a large number of low-cost ones, it can still average out to .75. look at it this way: of the 44 singles that result from eckstein's range deficit, a certain portion will trigger big innings, a larger portion will trigger small rallies, and the lion’s share will have no impact at all. let’s make some conservative estimates. say only a third of the bad-range basehits (brbs) lead to any scoring at all — that’s 15 instances, or once every 10 games. let’s further suppose that five of those brbs cost just one run, another five cost two, and the last five cost three runs . . . . . well, that adds up to 30 runs, very close to chronicler’s 33-run estimate. does three runs seem an unreasonable impact to assign a lonely dribbler through the infield? i don’t think so. it’s a cherished cliché that you can’t give a team four outs in an inning; the extra out turns small rallies into large rallies, or non-scoring innings into one- and two-run innings. in that regard, a groundball that’s missed because of poor range is the same as a groundball that’s booted for an error. either way, it’s an extra out.
in fact, errors provide another useful "common-sense" check on the chronicler’s 0.75-run estimate. if we accept that errors are analagous to bad-range basehits — both are outs the defense fails to make — then we can learn much by quantifying the defensive cost of a single error. and that’s easy. we know how many errors are committed over the course of a season, and we know how many runs result from those defensive lapses — they’re called "unearned runs." divide the one into the other, and there’s your value. in the american league in 2004, there were 1520 errors resulting in 900 unearned runs — or .59 runs per error. in the national league, 1646 errors led to 1001 unearned runs, or .61 runs per error.
that’s not quite .75 runs per misplay, although it’s in the ballpark. but keep in mind that some errors don’t put a runner on base, and thus are not completely analogous to bad-range basehits. i’m talking about pickoff attempts that get thrown down the rightfield line, singles that roll through an outfielder’s legs and let the batter reach second or third, relay throws that end up in the dugout. those errors inflate the scoring potential of runners who’ve already reached safely, but they do not turn negative scoring potential (ie, outs) into positive scoring potential (ie, baserunners). the errors in this category — and i have no idea what fraction of the total error population they account for — are less damaging than either a booted groundball or a brb, and hence they lower the average cost of errors relative to brbs. if we adjust for this factor, we move some distance closer to .75 runs / error.
so i have convinced myself — if not you, anolis — that every ball that grazes eckstein's outstretched glove as it bounces past will cost the cardinals 3/4 of a run.
and btw anolis ---- thx for the birthday wishes.
"If I read this correctly, Eckstein made 44 less outs than might have been expected, and the analysis suggests that this translated into allowing 33 more runs that expected. Can this be correct? Since the outs that Eckstein missed almost surely turned into singles, is the expected value of turning an out into a single 3/4 of a run? Seems high to me."
yeah, me too — at first. the 33-run estimate comes from the chronicles of the lads, an anaheim angels blogger who is bravely/foolishly attempting to draw meaningful conclusions from defensive statistics. the chronicler explicitly posits that an out by a shortstop prevents 3/4 of a run — i quote:
"I turned to Chris Dial's methodology, in which a run value is assigned to each out a defender makes. For instance, 98.7% of outs made by a SS prevent a single. A single is worth .47 runs. Each out is also just that: an out, which has a value of roughly .28 runs. So, 98.7% of the outs made by a SS prevent .75 runs. (The other 1.3% account for 1.06 runs each, because sometimes those screamers by the SS get through the gap and go to wall for extra bases.)"
in other words, a routine 6-3 groundout moves an inning one out closer to completion (preventing .28 runs) and wipes out the run-scoring potential of a single (.47 runs); add .28 and .47, and you get .75. i hear those gears turning, anolis — now you want to know who the hell chris dial is and whether his methodology makes any sense — and unfortunately, i can’t answer either question. but here's the link if you want to check his math.
i can however apply some common sense, and the exercise encourages me that .75 runs per single is in fact a reasonable estimate. let’s begin with an easy case: bases loaded, two outs, grounder up the middle — shortstop comes up a step slow and the ball trickles through. the hit results in two runs — and potentially more, because the inning continues. every run that scores subsequently would/could have been prevented by a rangier shortstop, so the cost of that particular grounder is over 2.0 runs.
here’s another case: men on first and second, one out, groundball up the middle. if the ss fields it, it’s a double play and the inning is over; if the ball gets through, one run scores, a runner winds up at third with one out, and the batter’s on at first base — the runner at third will score about .75 of the time, and the runner at first will score a certain percentage of the time as well. add it all up and the failure to reach that hypothetical grounder costs, on average, right around 2.0 runs.
of course, there will also be hits that dribble through with two outs and none on, and no harm will come of them. but if you average out a small number of high-cost cases with a large number of low-cost ones, it can still average out to .75. look at it this way: of the 44 singles that result from eckstein's range deficit, a certain portion will trigger big innings, a larger portion will trigger small rallies, and the lion’s share will have no impact at all. let’s make some conservative estimates. say only a third of the bad-range basehits (brbs) lead to any scoring at all — that’s 15 instances, or once every 10 games. let’s further suppose that five of those brbs cost just one run, another five cost two, and the last five cost three runs . . . . . well, that adds up to 30 runs, very close to chronicler’s 33-run estimate. does three runs seem an unreasonable impact to assign a lonely dribbler through the infield? i don’t think so. it’s a cherished cliché that you can’t give a team four outs in an inning; the extra out turns small rallies into large rallies, or non-scoring innings into one- and two-run innings. in that regard, a groundball that’s missed because of poor range is the same as a groundball that’s booted for an error. either way, it’s an extra out.
in fact, errors provide another useful "common-sense" check on the chronicler’s 0.75-run estimate. if we accept that errors are analagous to bad-range basehits — both are outs the defense fails to make — then we can learn much by quantifying the defensive cost of a single error. and that’s easy. we know how many errors are committed over the course of a season, and we know how many runs result from those defensive lapses — they’re called "unearned runs." divide the one into the other, and there’s your value. in the american league in 2004, there were 1520 errors resulting in 900 unearned runs — or .59 runs per error. in the national league, 1646 errors led to 1001 unearned runs, or .61 runs per error.
that’s not quite .75 runs per misplay, although it’s in the ballpark. but keep in mind that some errors don’t put a runner on base, and thus are not completely analogous to bad-range basehits. i’m talking about pickoff attempts that get thrown down the rightfield line, singles that roll through an outfielder’s legs and let the batter reach second or third, relay throws that end up in the dugout. those errors inflate the scoring potential of runners who’ve already reached safely, but they do not turn negative scoring potential (ie, outs) into positive scoring potential (ie, baserunners). the errors in this category — and i have no idea what fraction of the total error population they account for — are less damaging than either a booted groundball or a brb, and hence they lower the average cost of errors relative to brbs. if we adjust for this factor, we move some distance closer to .75 runs / error.
so i have convinced myself — if not you, anolis — that every ball that grazes eckstein's outstretched glove as it bounces past will cost the cardinals 3/4 of a run.
and btw anolis ---- thx for the birthday wishes.
posted by L Boros at 11:20 PM
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