Runs Allowed Records and Details
What is Runs Allowed ?
Runs are charged to a pitcher or team's pitcher when a hitter or baserunner scores for any reason. For a pitcher to be charged with the run allowed they must have been the pitcher the batter had a plate apperance against. An more complicated example of runs allowed is if pitcher A is removed from the game after allowing runners to reach second and third base and pitcher B gives up a home run. The two baserunners are charged to pitcher A, the hitter is charged to pitcher B. Generally, for Runs Allowed, lower is better. (Source)
What is a good Runs Allowed?
What does good Runs Allowed mean? "Good" baseball stats can be very subjective and mean different things to different people. I have attempted to quantify good and bad by taking season and career stats for MLB pitchers with a minimum number of pitched outs. In this case 100 for career and 50 for a season. To find good and bad within this cohort of players I calculated the first and third quartiles, anything between these quartiles I consider average. This makes up the middle 50% of players. In an example where higher is better for a stat, below the first quartile (bottom 25% of players) would be bad and above the 3rd quartile (top 25% of players) would be good. For stats where lower is better, flip around good and bad.
Career, Season, and Season Average Runs Allowed Records
For my hot take on Runs Allowed records most of the same rules apply from the first section. To be considered for my prestigious lists the player must meet a certain threshold of pitched outs. Since this is a Pitching stat to be considered for the career list the player must have over 100 pitched outs, for a season consideration the player must have had 75 pitched outs. Additionally, the player's final game must have been after 1899.