Measure Base Running Through EqBR
Measure base running proficiency through equivalent batter runs or extra base running percentage (XBRpct).
Twenty years ago, Bill James devised a set of formulas for measuring batting speed using readily available statistics. If you’re curious, here are the formulas:
- SpS1: speed score based on SB percentage
SpS1 = ((SB + 3) / (SB + CS + 7) - 0.4) * 20
- SpS2: speed score based on SB attempts
SpS2 = SQRT ((SB + CS) / ((H - 2B - 3B - HR) + BB + HP)) / 0.07
- SpS3: speed score based on triples
SpS3 = 3B / (AB–HR - K) / 0.02 * 10
- SpS4: speed score based on runs per time on base
SpS4 = (( R- HR) / (H + BB–HR - HP) - 0.1) / 0.04
- SpS5: speed score based on GDPs
SpS5 = (0.055–GDP / (AB–HR - K)) / 0.005
- Net speed score
Average of top four speed scores in the list
These measurements are useful, but they don’t take individual situations into account. For example, let’s consider SpS5. On average, a slow runner who follows a batter with a high on-base percentage will hit into fewer double plays than a similar runner who follows a batter with a high on-base percentage.
The Baseball America 2005 Prospect Handbook (Baseball America) has a great essay by James Click on a method for measuring base running. Aside from steals (successful and failed), good statistics aren’t available for measuring how well players run around the bases. In this hack, I explain quickly how to measure this statistic from the play-by-play data.
Equivalent Batter Runs
Click’s measurements are nice because they ...