THE BATcast: A new projection system from Derek Carty, similar to THE BAT but using only Statcast data
to project players (with the exception of non-contacted-ball outcomes like strikeouts and walks, which
use THE BAT’s original projection)
The rate of barrels, as per the official Statcast definition
“batted-ball events whose comparable hit types (in terms
of exit velocity and launch angle) have led to a minimum .500 batting average and 1.500 slugging
percentage since Statcast was implemented Major League wide in 2015.”
“How high, in degrees, a ball was hit by a batter,” as per the official Statcast definition
The “(Average)” version of Launch Angle is, as the
name suggests, the average launch angle of all balls a hitter contacted and Statcast recorded data on.
The average launch angle of a hitter’s batted balls that are within the top
one-third of his hardest struck batted balls. Coined by Tom
Tango, Senior Data Architect for MLBAM: “The idea being that the harder you hit the ball, the more
likely you ‘got all of it’, and so, the launch angle was your intended launch angle. You got it on the
sweetspot of the bat, and so, the byproduct of that is your… Sweetspot Launch Angle.”
The percentage of balls the batter hits with a launch angle between -4 and 26 degrees.
This range produces league average BABIPs over .300.
The percentage of balls the batter hits with a launch angle between 23 and 34
degrees. This range produces league average HR% over 20%.
The percentage of balls the batter hits with a launch angle over 38 degrees. This
range indicates an extreme uppercut swing, which can lead to power but also kills batting average and
BABIP.
The standard deviation of the launch angle of all of a hitter’s batted
balls – i.e. how tightly clustered a hitter’s launch angles are (the smaller the number, the tighter). Alex
Chamberlain originally led research into this stat
as a proxy for bat control and contact skills. It is one of the best descriptive indicators
of BABIP and a good predictive one.
“How fast, in miles per hour, a ball was hit by a batter,” as per the
official Statcast definition. The “(Average)” version of Exit Velocity is, as
the name suggests, the average exit velocity of all balls a hitter contacted and Statcast recorded data on.
The average exit velocity of the top 5% through 25% of the hardest balls the
player hit (note this does not include balls in the top 5%)
The percentage of balls hit into the air by a batter that have an exit
velocity of 100 mph or greater
Created by Derek Carty, it is a measure of how evenly a player hits the ball to all fields (i.e.
sprays the ball). It is calculated by taking the absolute value of the percentage of balls hit to each field
(pull, center, opposite) minus .33, and adding up the values for all three fields. A hitter who hits balls
evenly to all fields (i.e. 33% to each field) will have a Spray Score of 0. A hitter who hits all balls to one
field will have a Spray Score of 1.33. The lower Spray Score is a good indicator of contact ability.
“A measurement of a player's top running speed, expressed in ‘feet per second in a
player's fastest one-second window’,” as per the official Statcast definition
Note: Statcast stats are calculated live by in-ballpark cameras and radar. These occasionally fail to record data on certain batted balls. All data and projections displayed at EV that rely on Statcast data identify these missed balls and estimate what they should have been. Internal tests showed this to be slightly more accurate than either ignoring the missing data or using MLB's imputed data.
