Context-Neutral Win Values Across Different Run-Scoring Environments: 1968 versus 2000
The win values of events are highly dependent on the run-scoring environment in which they take place. This is most strikingly observed if we compare net win values for the lowest-scoring and highest-scoring run environments of the Retrosheet Era. The lowest-scoring league for which I have complete play-by-play data is the 1968 American League, in which teams averaged 3.41 runs per game. The highest-scoring league for which I have complete play-by-play data is the 2000 American League (i.e., games played in American League ballparks in 2000), at 5.31 runs per game.
Positive Offensive Events
The first set of numbers for comparison is for positive offensive events: singles, doubles, triples, home runs, and walks. The numbers for "singles" here include ROE (reached on error) and "walks" include hit-by-pitches:
Base Hits / Batters safe on Balls-in-Play
|
Runs/Game |
HR |
T |
D |
S/ROE |
W/HBP |
IW |
1968 AL |
3.41 |
0.1707 | 0.0974 | 0.0734 | 0.0423 | 0.0323 | 0.0050 |
2000 AL |
5.31 |
0.1253 | 0.0699 | 0.0511 | 0.0352 | 0.0300 | 0.0084 |
Not surprisingly, offensive events were more valuable in 1968 than in 2000. Runs were 55.7% more plentiful in the 2000 AL than in 1968. Home runs were 36.2% more valuable in 1968 than in 2000. Extra-base hits are similarly more valuable: 39.4% more valuable for triples, 43.6% more valuable for doubles. The difference in win values is a fair bit less for simply reaching first base, however (20.2% for a single, 7.7% for a walk).
Why? Because runs were much rarer in 1968, the value of a guaranteed run - a home run - was huge, as was the value of getting into scoring position. The value of simply getting on first base, on the other hand, is relatively slight because, in 1968, if you walked, the odds were very strong that you weren't going to get much farther than first base anyway.
The one offensive event here that was less valuable to the hitting team in 1968 is the intentional walk. When hits are at a premium, there's less downside risk to the pitching team of walking a batter because, as with an unintentional walk, the odds are very high that the next batter isn't going to do anything to put any runs on the scoreboard.
Outs
Win values for outs in general as well as for different types of outs are shown next.
Batting Outs
|
All |
K |
Other |
1968 AL |
-0.0232 | -0.0219 | -0.0236 |
2000 AL |
-0.0245 | -0.0225 | -0.0252 |
The average win value of an out is surprisingly constant between these two years. This is because the number of outs in a game does not change with the run environment - there are 27 outs in a 9-inning baseball game, no matter how many hits, walks, and runs are accumulated in those nine innings.
Baserunning
The next table shows net offensive values for stolen bases, caught stealings, and advancements on wild pitches and passed balls.
Stolen base numbers here include all baserunner advancements on stolen-base attempts, including defensive indifference, balks, and errors on pickoffs. Caught stealing figures include successful pickoffs as well.
Stolen Base Success Rates
|
SB |
CS |
WP |
Break-even |
Actual |
1968 AL |
0.0264 | -0.0446 | 0.0347 | 62.8% |
64.4% |
2000 AL |
0.0146 | -0.0381 | 0.0218 | 72.2% |
68.7% |
As with earlier offensive events, the increased value of the positive offensive events - stolen bases and wild pitches - are greater than the increased negative value of negative offensive events - caught stealing. Put together, the break-even success rate for stolen bases was far lower in 1968 -