PEAR Run Value (PRV)

PEAR Run Value is how many runs better than average a player is, per 100 plate appearances for a hitter or per 100 batters faced for a pitcher. It is a rate, not a season total: it says how good the player is, not how much he played.

• It starts from play-by-play: each plate appearance is worth the runs its outcome usually adds or costs.
• It is adjusted for the pitchers or hitters the player faced and for the park.
• Stolen bases, caught stealing and pickoffs count, and for pitchers so do wild pitches and balks.
• A pitcher's PRV leaves out his team's fielding.
• A small sample is pulled toward what would be expected of the player, so 20 hot plate appearances don't top the list.

• 0 is an average player in the division. Higher is better for hitters and pitchers alike.
• Hitters and pitchers are on one scale, and so is every season of a division.
• It is scaled so that a player one run better this season tends to be one run better next season.
• For a season total, multiply PRV by plate appearances (or batters faced) and divide by 100.

• players (the leaderboard), roster and player/{player_id} carry PRV.
• Beside it: RE24 (runs added by base-out situation), wRE24 (the same, adjusted for opponent and park) and WPA (see win probability).

• Each division has its own scale. A +4 in D3 is not a +4 in D1.
• It needs play-by-play, so it is blank for NAIA and for games without it.
• It does not measure fielding.