Baseball Prospectus Glossary
View Glossary Entries by
Runs scored (for hitters) or allowed (pitchers).
Runner on first. In the RBI opportunity report, refers to the number of times a batter came to the plate with a runner at first base.
Percentage of runners on first base batted in
Runners on first base batted in
Runner on second. In the RBI opportunity report, refers to the number of times the batter came to the plate with a runner at second base.
Percentage of runners on second base batted in
Runners on second base batted in
Runner on third. In the RBI opportunity report, refers to the number of times the batter came to the plate with a runner at third base.
Percentage of runners on third base batted in
Runners on third base batted in
Actual team runs allowed. Can also stand for Run Average--runs allowed, earned or otherwise, divided by innings pitched, times 9.
Park and league normalized Run Average. Similar to ERA+ found in Total Baseball, but based on RA rather than ERA.
Runs Allowed per Game.
For Pitchers: Runs above average. At its simplest, this would be the league runs per inning, times individual innings, minus individual runs allowed. However, we have gone one step beyond that, because being 50 runs above average in 1930, in the Baker Bowl, doesn't have the same win impact as being +50 in the 1968 Astrodome. The league runs per inning need to be adjusted for park and team hitting (and difficulty, for the alltime RAA), and then you can multiply by individual innings and subtract individual runs. Finally, that quantity needs to be win-adjusted. See win-adjustment. For Fielders: Runs above average at this position, similar to Palmer's Fielding Runs as far as interpretation is concerned.
Rank by Equivalent Average
Rank by equivalent strikeouts per 9 innings
Rank by Fielding Runs Above Replacement
Rank by Wins Expected Above Replacement Player
Runs Above Position: The number of Equivalent Runs this player produced, above what an average player at the same postion would have produced in the same number of outs.
Runs Above Replacement.
For a fielder, it is simply Runs Above Replacement for the position, where a replacement-level fielder is determined to be about 20 runs below average for the position; the number varies slightly depending on the number of balls in play.
Runs Above Replacement, Position-adjusted. A statistic that compares a hitter's Equivalent Run total to that of a replacement-level player who makes the same number of outs and plays the same position. A "replacement level" player is one who has 22.1 fewer EqR per 486 outs than the average for that position. For the overall league average (.260), that corresponds to a .230 EqA and a .351 winning percentage.
Essentially, this is the Equivalent Average analog of VORP.
Runs Batted In.
Number of runs a batter has driven in per runner on base during a batter's plate appearances. Defined as total baserunners/RBI (NB: Runners on base are other than the batter himself--RBI's resulting from a batter driving himself in on home runs are removed).
RBI + R - HR. Used in fantasy baseball to approximate runs created in a simple fashion.
RBI Rate -- RBI per plate appearance
Win-Loss record for a particular team and run differential
Relief Percentage -- positive relief decisions (saves and holds) divided by total relief decisions (saves, holds, blown saves)
The number of runs an average player would have produced relative to replacement level.
Raw equivalent average, the first step towards building the EqA. In its fullest form, REQA = (H + TB + 1.5*(BB + HBP + SB) + SH + SF) divided by (AB + BB + HBP + SH + SF + CS + SB). REQA gets converted into unadjusted equivalent runs, UEQR.
Runners On Base: the number of runners on base during a batter's plate appearances.
Reached On Error: when a batter reaches base as a direct result of a fielding error.
Percentage of plate appearances that result in the batter reaching base on an error.
Reached On Error Rate -- reaching on error per plate appearance.
This indicates whether or not a player was a rookie during that season. To be a rookie, a player must have fewer than 130 at-bats and 50 innings pitched.
MLB will exclude players who have spent at least 45 days on a 25-man roster from eligibility for rookie of the year. Due to lack of service time data historically we do not exclude those players, so the rookie flag may not correspond exactly with award eligibility.
Runs Prevented. The extra number of runs an average pitcher would have allowed in the same number of innings pitched (adjusted for park and league). RP greater than zero indicates that the pitcher allowed fewer runs than an average pitcher (i.e. he's better than average). Negative RP indicates the pitcher allowed more runs than an average pitcher (i.e. he's worse than average).
A player's runs per plate appearance, relative to the league average - 100 means average, 120 is 20% better than average, etc.
RPA+ is computed as:
RPA/lgRPA
Where lgRPA is the league runs per plate appearance, adjusted to match a player's run environment (adjusted for park, in other words). The scale of RPA+ should correspond with that of OPS+ and similar metrics; it will produce the same rank order as True Average, however.
Read more here
Runs Per Inning. RPI is the average number of runs scored per inning by a given team or lineup, used to calculate Win Expectancy. RPI is a measure of the strength of a team's offense (or conversely, the strength of the opposing team's pitching staff).
Replacement level MLV rate. Runs/game contributed by a batter beyond what a replacement level player at the same position would hit in a team of otherwise league-average hitters. The comparable season total is RPMLV. It differs from VORPr and VORP only in that it is solely based on batting performance whereas VORP includes basestealing.
Actual runs scored by a team.
Runs Scored per Game.
Denotes position of runners on base. For example, 103 denotes runners on first and third
Runs scored Rate -- Runs scored (typically by a player) per plate appearance
Runs charged to a pitcher before he is removed from the game (i.e. excluding runners on base when he exited who may have been allowed to score by a subsequent pitcher)
A way to look at the fielder's rate of production, equal to 100 plus the number of runs above or below average this fielder is per 100 games. A player with a rate of 110 is 10 runs above average per 100 games, a player with an 87 is 13 runs below average per 100 games, etc.
See Rate. Rate2 incorporates adjustments for league difficulty and normalizes defensive statistics over time.
The first step in putting together equivalent average.
In its fullest form,
RawEQA = (H+TB+1.5*(BB+HBP+SB)+SH+SF-IBB/2) / (PA+SB+CS),
where PA=AB+BB+HBP+SH+SF. Feel free to drop any variable that isn't readily available.
Whether the injury suffered is reoccurring.
Release:Tunnel Ratio - This stat shows us the ratio of a pitcher's release differential to their tunnel differential. Pitchers with smaller Release:Tunnel Ratios have smaller differentiation between pitches through the tunnel point, making it more difficult for opposing hitters to distinguish them in theory.
Release:Tunnel Ratio - This stat shows us the ratio of a pitcher's release differential to their tunnel differential. Pitchers with smaller Release:Tunnel Ratios have smaller differentiation between pitches through the tunnel point, making it more difficult for opposing hitters to distinguish them in theory.
In Team Audit or Playoff Odds Report context, the rank of a team in the grouping and sort currently active.
For instance, the default view of Team Audit is sorted by GB ascending and grouped by division. In this view, the division leaders will all rank 1, second place teams will rank 2, etc. Any teams that have the same values on the sort column will have the same Rnk.
To quickly find a team's rank in any stat, sort by that stat and refer to this column. For example, if you wanted to determine where the Padres ranked in RS/G in all of MLB, sort by the RS/G header, set your grouping to MLB, and refer to this column.
How many runs are likely to score in a certain base-out situation.
The number of runs expected to score from a particular event, based on historical data.
| 
