pitchid: a unique identifier for each pitch.pitcherid: identity of the pitcher.yearid: year in which the pitch occurred.throws: handedness of the pitcher.height: height in inches of the pitcher.initspeed: initial speed of the pitch as it leaves the pitcher's hand, reported in MPHbreakx: horizontal distance in inches between where a pitch crossed the plate and where a hypothetical spinless pitch would have, where negative is inside to a right-handed hitter.breakz: vertical distance in inches between where a pitch crossed the plate and where a hypothetical spinless pitch would have, where negative is closer to the ground.initposx: horizontal position of the release point of the pitch. The position is measured in feet from the center of the rubber when the pitch is released, where negative is towards the third-base side of the rubber.initposz: vertical position of the release point of the pitch. The position is measured in feet above the ground.extension: distance in feet in front of the pitching rubber from which the pitcher releases the ball.spinrate: how fast the ball is spinning as it leaves the pitcher's hand, reported in RPMtype: type of pitch that was thrown