Nats Stats: How many runs should we expect?
So, as we were puzzling over the mathematically-inexplicable suckitude of the Nats yesterday, commenter Graysnail wondered out loud what the Nats' situational run expectancy looked like. Don't worry, ye stats-averse, this isn't as complex as the name sounds. It's the number of runs you score (on average) starting from a given number of outs and men on base. For example, the average team scores 2.27 runs before ending the inning if they have the bases loaded and no outs. The run expectancy with bases-loaded, no outs is 2.27. Here is Baseball Prospectus' Run Expectancy for the 2009 season so far (including both AL and NL teams):
| On Base | no out | 1 out | 2 out |
| --- | 0.52 | 0.28 | 0.10 |
| 1-- | 0.88 | 0.55 | 0.23 |
| -2- | 1.12 | 0.69 | 0.31 |
| --3 | 1.30 | 0.96 | 0.40 |
| 12- | 1.48 | 0.93 | 0.46 |
| 1-3 | 1.77 | 1.19 | 0.57 |
| -23 | 2.01 | 1.42 | 0.59 |
| 123 | 2.27 | 1.57 | 0.78 |
After a big data dump from baseball-reference and a bit of SQL, I'll give you the same for the Nats so far this season after the jump:
| On Base | no out | 1 out | 2 out |
| --- | 0.47 | 0.25 | 0.08 |
| 1-- | 0.77 | 0.42 | 0.14 |
| -2- | 1.10 | 0.67 | 0.30 |
| --3 | 0.33 | 0.81 | 0.40 |
| 12- | 1.69 | 0.74 | 0.37 |
| 1-3 | 2.00 | 0.97 | 0.20 |
| -23 | 1.90 | 1.44 | 0.17 |
| 123 | 1.89 | 1.29 | 0.47 |
Before you scream too loudly about the inability to score from 3rd with no outs, keep in mind that's based on only three instances. The "insufficient stats" problem for some of the no-out cases aside, the bases-loaded failures that are so prominent in our memories seem to be real. The Nats score 0.3 fewer runs than the average team with the bases loaded. Most of the other combinations are fairly close to average (within 0.2 runs), and some are slightly better--runners first-and-second or first-and-third with no outs, for example. The Nats do seem to be consistently below average with multiple men on base and two outs. I'm not sure how much the results of the baseline run expectancy gets skewed from having both AL and NL mixed together, and I might have a go at figuring an NL-only run expectancy if I can get the baseball-reference data hamsters to spin out the data.
So, what does it mean? Aside from "MOAR RUNZ PLZ," I'm not sure--but I thought I'd share with the class.
1 recs |
10 comments
Comments
Are you on vacation? You prolific bastid...
Vivian Jaffe: "Have you ever transcended space and time?"
Albert Markovski: "Yes. No. Uh, time, not space... No, I don't know what you're talking about."
by Ed Chigliak on Jul 15, 2009 4:39 PM EDT via mobile reply actions 0 recs
How many runs should we expect?
MORE !
by Berndaddy on Jul 15, 2009 5:26 PM EDT reply actions 0 recs
Top 20 Rookies at the Break as per Baseball America
- - Jordan Zimmermann – way to go Jordan
And as Rodney Dangerfield said
“Remember look out for number one and don’t step on number two.”
Cause he has a wicked fastball…( I know not so funny… hey look a bunny….)
by Berndaddy on Jul 15, 2009 5:30 PM EDT reply actions 0 recs
Wait til you see my "bold prediction" in the upcoming mid-season roundtable...
Vivian Jaffe: "Have you ever transcended space and time?"
Albert Markovski: "Yes. No. Uh, time, not space... No, I don't know what you're talking about."
by Ed Chigliak on Jul 15, 2009 5:44 PM EDT via mobile up reply actions 0 recs
Nats don't sign Strasburg?
::poke::
by Graysnail on Jul 15, 2009 7:12 PM EDT up reply actions 0 recs
Hm.
My suspicion is that the Nats’ hitting with two outs and pitching with two outs are significant outliers. With that being said, the sample sizes are still within range of the mean (I think) for all these cases. If run expectancies are down for the batters with two outs and up for the pitchers with two outs, that would help to explain in part what we’re chalking up to bad luck, right?
It’d be impossible to figure this out for the pitching, right? I can only imagine what kind of hell that’d be.
by Graysnail on Jul 15, 2009 7:18 PM EDT reply actions 0 recs
And thanks for doing this, btw.
This kind of stuff is insanely fascinating to me.
by Graysnail on Jul 15, 2009 7:23 PM EDT up reply actions 0 recs
You know, I think I could figure this out for pitching...
…I’ve been dumping all the data for the other teams in the league so I could figure out the AL/NL split, and once I’ve got a big database of every PA in MLB for the first half, well—just switch the “batting for” and “batting against” fields! By which I mean, STOP GIVING ME IDEAS!! Are you trying to get me fired? ;) Don’t expect me to turn it around quite as quickly this time, not with actual baseball to be played tomorrow.
"It's not a secret, you don't need to be an expert on math to know that walks plus errors equals runs...." --Mannyger Acta
by Doghouse on Jul 15, 2009 8:04 PM EDT up reply actions 0 recs
No worries, I'm not in a hurry to know that.
I’d do it myself if I knew a damn thing about database querying & building. Trust me, I could give you too many ideas about these things. ;)
by Graysnail on Jul 16, 2009 8:29 PM EDT up reply actions 0 recs

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