Armside

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Squared Up% / Squared Up%

Batter

Squared-up batted balls as a share of competitive contact (competitive swings that were not whiffs, fouls included). A batted ball is squared up when its exit velocity is at least 80% of the most it could have been from that bat speed and the pitch's speed at the front of the plate. See runbook section 58.

Agreement with Savant

Checked nightly. Agreement tolerance: ±4 — in swings, through its numerator squared_up; the rate itself is only that count over a count that is also judged (runbook §60).

Pitcher

Squared-up batted balls allowed as a share of competitive contact against this pitcher (competitive swings that were not whiffs, fouls included). Squared up: exit velocity at least 80% of the most it could have been from that bat speed and the pitch's speed at the front of the plate. See runbook section 58.

Agreement with Savant

Checked nightly. Agreement tolerance: ±4 — in swings, through its numerator squared_up; the rate itself is only that count over a count that is also judged (runbook §60).

Shown for: batter and pitcher.

Formula

sum(squared_up)::real / NULLIF(sum(comp_contact), 0) — squared-up batted balls over competitive contact (competitive swings that were not whiffs, fouls included). A batted ball is squared up when launch_speed / (1.23 × bat_speed + 0.23 × plate_speed) >= 0.80, where plate_speed is the pitch's speed at the front of the plate solved from the nine-parameter fit (vx0, vy0, vz0, ax, ay, az at y = 50 ft to y = 17/12 ft).

Inputs

Era caveats

Bat tracking begins 2023-07-14

Savant's bat-tracking fields -- bat speed, swing length, attack angle, attack direction and swing tilt -- are on the wire from 2023-07-14. Every bat-tracking column is empty for 2015-2022, 2023 covers the second half of the season only, and a span that starts earlier counts only the swings from that date. Parity is unaffected: Savant's own 2023 boards carry the same partial season, and the six closed season-sides reconcile to the player. (runbook §59)

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