Last week, I examined a list of hitters who were near the top of the league in exit velocity, while also lagging behind their peers in terms of expected results on their batted balls. For reference, I showed the following chart to explain how batters have performed during 2017 (updated for current games over the past week):
|z-score||Avg xOBA||Avg EV|
Average EV = 87.28
Variance = 7.12
Std Dev = 2.67
I didn’t do well at explaining this chart, last week. To reiterate, at the footer of the table you can see see that there are currently 395 players with over 30 balls in play in 2017. The numbers shown in each z-score row, display the average metrics for all players with exit velocities in excess of that performance level. For example, those with an exit velocity z-score in excess of 2 have average an exit velocity of 93.96, with an expected OBA of .406 (on same scale as wOBA). Please let me know if any confusion surrounds this chart.