CSS Button No Image Css3Menu.com

Baseball Prospectus home
  
  
Click here to log in Click here for forgotten password Click here to subscribe

No Previous Article
<< Previous Column
Aim For The Head: Walk... (07/12)
Next Column >>
Aim For The Head: Feed... (07/27)
No Next Article

July 19, 2001

Aim For The Head

Pitches and Game Length

by Keith Woolner

This week's question comes from Nate Calvin, who also happens to be an old college buddy of mine:

Sandy Alderson is in hot water for trying to get the umps to drop game pitch counts from 285 to 270 by calling more strikes. I believe pitchers average a little over five pitches per out, so three extra strikeouts a game would easily cover the difference. What's the current strike percentage, and based on the situational tables, what strike percentage would be required to meet Sandy's target?

(Suspected result: the necessary change does not impact the character of the game whatsoever.)

This has certainly been a hot topic lately, and the BP staff has been getting many questions about it. I drew the short straw, so I get to tackle this one.

I'm going to approach the question a little differently that Nate has suggested. I'm going to look at all the games so far this year, and break them down by total pitches thrown. More specifically, I'm going to exclude extra-inning games and rain-shortened games, and just look at "normal" length games of between 17 and 18 total pitched innings. Let's look at some selected averages for such games so far this year:


NP_RANGE  Games   Strike%    RA  AVGTIME  BFP/G    AVG  OBP  SLG  OPS  AVG_NP
All        1139    62.49%  4.95    175.9     77   .260 .330 .422  752  285.29

Some of the non-obvious headings are:

  • NP_RANGE is the pitch counts that a game had to have in order to be considered (e.g., 250-259). In this case, "All" means all qualifying games.

  • Strike% is the percentage of all pitches that were strikes

  • AVGTIME is the average length of a game, in minutes

  • BFP/G is the average number of batters faced by each team's pitching staff in a game.

  • AVG_NP is the average number of pitches thrown per game for this set of games.

In analyzing the different ranges of pitch counts, I'm going to make an assumption (which may or may not be a good one), that changing the major-league average pitch count total will lead to overall results comparable to those games that are already in that range. In other words, to see what happens when the average pitch counts of all games drops to 270, look at current games in which about 270 pitches were thrown. I'll use ranges spanning 10 pitches (e.g., 250-259 pitches, 260-269 pitches, etc.) as the different sets of games. If the assumption is at least plausible, then the averages for the 280-289 pitch count range should be reasonably close to the averages for all games:


NP_RANGE  Games   Strike%    RA  AVGTIME  BFP/G    AVG  OBP  SLG  OPS  AVG_NP
ALL        1139    62.49%  4.95    175.9     77   .260 .330 .422  752  285.29
280-289     120    62.70%  5.04    176.2     77   .264 .333 .422  755  286.83

It looks like looking only at games around the mean pitch count (NP_RANGE = 280-289) gives a decent approximation to the rates of the entire data set (ALL). If this holds true throughout the range of pitch counts we want to examine, then to see what baseball would be like if league-wide averages were driven down to 270 NP/G, we can look at what happens in games around 270 pitches.

NP_RANGE

G

STRIKE%

RA

AVGTIME

BFP/G

AVG

OBP

SLG

OPS

AVG_NP

<220

17

68.71%

2.17

130.9

64

.207

.236

.330

566

205.88

220-229

25

65.85%

2.87

140.4

67

.202

.245

.335

580

225.00

230-239

56

64.71%

2.99

148.4

67

.221

.270

.349

618

234.95

240-249

87

64.49%

3.32

156.9

71

.229

.284

.360

644

245.36

250-259

101

63.89%

3.65

165.0

73

.234

.292

.367

660

255.43

260-269

137

63.15%

3.98

166.2

74

.240

.303

.379

683

264.34

270-279

127

62.83%

4.57

171.4

75

.252

.316

.409

725

274.62

280-289

120

62.70%

5.04

176.2

77

.264

.333

.422

755

284.46

290-299

125

61.76%

5.30

181.3

78

.264

.341

.437

778

294.41

300-309

109

61.86%

5.87

185.4

79

.280

.354

.466

821

304.05

310-319

90

60.95%

6.36

192.0

81

.288

.368

.474

842

314.16

320-329

49

60.70%

6.83

199.2

83

.296

.382

.495

877

323.76

330-339

57

60.64%

7.32

209.7

88

.305

.392

.492

884

333.91

>=340

39

59.87%

8.41

216.6

91

.321

.412

.534

945

362.28

ALL

1139

62.49%

4.95

175.9

77

.260

.330

.422

752

285.29

First, let's notice that there is a direct correlation between the number of pitches thrown, and the percentage of pitches thrown for strikes. Presumably, calling more strikes would indeed lower pitch counts. Next, notice that run scoring rises as pitch counts rise. Neither phenomenon is particularly unexpected, but the strength of the relationship may not be obvious until you see the data for yourself. A chart makes the point more strongly:

Run scoring rises roughly linearly with total pitch count, while the relationship between pitch count and strike percentage looks slightly nonlinear, but again clearly showing the intuitive result that higher pitch counts are associated with throwing fewer strikes.

Returning to Nate's question and suspected result, the implication of this analysis is that reducing overall pitch counts by increasing the strike percentage to the required level would actually have a significant impact on the game. Interpolating from the table given above, to obtain a 270 average pitch-count, the percentage of strikes called would need to increase from the current 62.5% to about 63%. Half a percent sounds like a small amount, but the impact is significant. Run scoring would decrease from the current 4.95 RA to an expected 4.10 RA, a level not seen since the early 1990s.

But what of the other supposed benefit of speeding up games? How much time would we expect to be shaved off the average length of a game if we reduced the pitch counts? Again, there's a clear relationship between pitch counts and the time it takes to play a nine-inning major-league game.

Shortening the time between innings and reducing the number of warmup tosses a pitcher gets may help keep the game moving, but one of the best ways to complete a game in less than three hours is to have pitchers who work efficiently. Interpolating the data in the table again, cutting pitch counts from 285 to 270 should knock about nine minutes off the length of a typical nine-inning game, bringing the average down to a lean two hours, 47 minutes.

So, if you believe that a 5% reduction in game time, and a 17% reduction in scoring, is a big change in the character of the game, then Nate's suspicions are a little off: reducing pitch counts would have a big effect on baseball. Calling fractionally more strikes would single-handedly counteract the offensive explosion of the mid-to-late 1990's.

As usual, some big caveats apply to this analysis. First, I'm assuming that since games around 285 pitches are an adequate model for a league that averages 285 pitches, that a similar relationship exists for other offensive and pitch-count levels. Second, I'm really analyzing the effect of games in which the current umpiring style produced a certain percentage of strikes, with a presumably random distribution of strikes within the strike zone. If umpires change what they consider to be a strike (calling them strikes where they used to be balls), the impact on the game could be considerably different from the approximation used here. It's the borderline pitches that will change from balls to strikes, so you're adding more strikes in a decidedly non-random fashion. Since those pitches are probably harder to hit, the batter may be put at even more of a disadvantage than shown here.

On the other hand, we're also not considering how batters and pitchers might react to the new strike zone. Would batters become more aggressive earlier in the count, and drive pitch counts further down as a side effect, but without actually lowering offense anymore than expected? Would pitchers and catchers change how they work a batter, relying more on nibbling at the fringes of a generous strike zone, and less on challenging them in a tiny zone in the batter's wheelhouse? How long would such a strike zone last? Would pitchers, benefiting from lower workloads, get less tired between starts, and be stronger in each outing than before? Is there a feedback effect that would tip the scales more and more towards reduced run scoring, or would there be counterbalances that would pull the game back towards high-offense, long-running games?

While this analysis doesn't provide answers to all of those questions, it does suggest that the implications of even a 15-pitch reduction would be significant, and thus changes towards that goal should not be taken lightly.

Keith Woolner is an author of Baseball Prospectus. You can contact him by clicking here.

Keith Woolner is an author of Baseball Prospectus. 
Click here to see Keith's other articles. You can contact Keith by clicking here

Related Content:  Pitch Counts,  Pitches

0 comments have been left for this article.

No Previous Article
<< Previous Column
Aim For The Head: Walk... (07/12)
Next Column >>
Aim For The Head: Feed... (07/27)
No Next Article

RECENTLY AT BASEBALL PROSPECTUS
Before They Were Prospects
Fantasy Article Fantasy Team Preview: Baltimore Orioles
Premium Article Rumor Roundup: The Ace Chase, the Rays' Face...
Premium Article Daisy Cutter: Jon Lester's New Peers
Premium Article Prospect Mechanics
Moonshot: A New View of Plate Discipline, Pa...
The Lineup Card: Nine of the Worst Baseball ...

MORE FROM JULY 19, 2001
The Daily Prospectus: Venting

MORE BY KEITH WOOLNER
2001-08-16 - Aim For The Head: More Reaching on Errors
2001-08-02 - Aim For The Head: Reaching on Errors
2001-07-27 - Aim For The Head: Feedback
2001-07-19 - Aim For The Head: Pitches and Game Length
2001-07-12 - Aim For The Head: Walk Rate Spikes
2001-06-26 - Aim For The Head: Fan Satisfaction
2001-06-20 - Aim For The Head: Response Rates
More...

MORE AIM FOR THE HEAD
2001-08-16 - Aim For The Head: More Reaching on Errors
2001-08-02 - Aim For The Head: Reaching on Errors
2001-07-27 - Aim For The Head: Feedback
2001-07-19 - Aim For The Head: Pitches and Game Length
2001-07-12 - Aim For The Head: Walk Rate Spikes
2001-06-26 - Aim For The Head: Fan Satisfaction
2001-06-20 - Aim For The Head: Response Rates
More...