StatLab

Learn the stats, step by step

From the box score to WAR in six levels. Every lesson uses live 2026 data, tells you how the stat lies, and takes about three minutes.

0The stats you already know

…and exactly how each one lies to you. No new stats yet — just healthy doubt.

  1. 1.Batting average: the beloved liar
  2. 2.HR, RBI, Runs: whose stat is it anyway?
  3. 3.Pitcher wins: the fake stat
  4. 4.ERA: better, but still noisy
  5. 5.Errors and fielding %: grading the wrong thing
  6. 6.Capstone: read a box score with new eyes

1Rates, not counts

Per-opportunity thinking: the single biggest upgrade a fan can make.

  1. 1.OBP: not making outs is the whole job
  2. 2.SLG & ISO: hits are not created equal
  3. 3.OPS: the good-enough shortcut
  4. 4.K% and BB%: rates for the pitcher's soul
  5. 5.WHIP: the fantasy classic
  6. 6.Capstone: judge a hitter from a slash line

2Luck, context, and the 100 scale

Separate skill from noise; meet park adjustment and '100 = average'.

  1. 1.BABIP: the luck detector
  2. 2.Sample size: when does hot become real?
  3. 3.Park factors: where you play matters
  4. 4.OPS+ and ERA+: the 100 scale
  5. 5.Capstone: spot the fluke

3Linear weights

Every event has a run value. This currency unlocks everything after it.

  1. 1.Run values: pricing every event
  2. 2.wOBA: OBP with correct prices
  3. 3.wRAA → wRC+: from rate to runs to the 100 scale
  4. 4.FIP: judge pitchers on what they control
  5. 5.xFIP: FIP's what-if cousin
  6. 6.Capstone: argue without ERA

4Statcast

Measure the ball, not the outcome — exit velo, barrels, expected stats, and the red sliders.

  1. 1.Exit velocity & launch angle: measuring the swing itself
  2. 2.Barrels & hard-hit%: the magic contact window
  3. 3.xBA, xSLG, xwOBA: what deserved to happen
  4. 4.The gap: finding breakouts and frauds
  5. 5.The arsenal: velo, spin, movement, whiffs, chases
  6. 6.Pitch run value: grading every single pitch
  7. 7.Sprint speed & OAA: legs and gloves, finally measured
  8. 8.Capstone: reading a Savant page

5Total value

Replacement level, position, and WAR — a framework to argue with, not worship.

  1. 1.Replacement level: better than whom?
  2. 2.Positional adjustment: a .750 OPS shortstop ≠ a .750 OPS first baseman
  3. 3.WAR: assembling the whole player
  4. 4.WPA & leverage: the story stats
  5. 5.Projections: forecasting without a crystal ball
  6. 6.Final capstone: the who's-better argument