Baseball batting {plyr} | R Documentation |
This data frame contains batting statistics for a subset of players collected from http://www.baseball-databank.org/. There are a total of 21,699 records, covering 1,228 players from 1871 to 2007. Only players with more 15 seasons of play are included.
Variables:
data(baseball)
A 21699 x 22 data frame
http://www.baseball-databank.org/
baberuth <- subset(baseball, id == "ruthba01") baberuth$cyear <- baberuth$year - min(baberuth$year) + 1 calculate_cyear <- function(df) { transform(df, cyear = year - min(year), cpercent = (year - min(year)) / (max(year) - min(year)) ) } baseball <- ddply(baseball, .(id), calculate_cyear) baseball <- subset(baseball, ab >= 25) model <- function(df) { lm(rbi / ab ~ cyear, data=df) } model(baberuth) models <- dlply(baseball, .(id), model)