R: Pitching table

Pitching {Lahman} | R Documentation

## Pitching table

### Description

Pitching table

### Usage

    data(Pitching)

### Format

A data frame with 44139 observations on the following 30 variables.

`playerID`

  Player ID code

`yearID`

  Year

`stint`

  player's stint (order of appearances within a season)

`teamID`

  Team; a factor

`lgID`

  League; a factor with levels `AA` `AL` `FL` `NL` `PL` `UA`

`W`

  Wins

`L`

  Losses

`G`

  Games

`GS`

  Games Started

`CG`

  Complete Games

`SHO`

  Shutouts

`SV`

  Saves

`IPouts`

  Outs Pitched (innings pitched x 3)

`H`

  Hits

`ER`

  Earned Runs

`HR`

  Homeruns

`BB`

  Walks

`SO`

  Strikeouts

`BAOpp`

  Opponent's Batting Average

`ERA`

  Earned Run Average

`IBB`

  Intentional Walks

`WP`

  Wild Pitches

`HBP`

  Batters Hit By Pitch

`BK`

  Balks

`BFP`

  Batters faced by Pitcher

`GF`

  Games Finished

`R`

  Runs Allowed

`SH`

  Sacrifices by opposing batters

`SF`

  Sacrifice flies by opposing batters

`GIDP`

  Grounded into double plays by opposing batter

### Source

Lahman, S. (2016) Lahman's Baseball Database, 1871-2015, 2015 version, http://www.seanlahman.com/baseball-archive/statistics/

### Examples

    # Pitching data

    require("dplyr")

    ###################################
    # cleanup, and add some other stats
    ###################################

    # Restrict to AL and NL data, 1901+
    # All data re SH, SF and GIDP are missing, so remove
    # Intentional walks (IBB) not recorded until 1955
    pitching <- Pitching %>%
                   filter(yearID >= 1901 & lgID %in% c("AL", "NL")) %>%
                   select(-(28:30)) %>%  # remove SH, SF, GIDP
                   mutate(BAOpp = round(H/(H + IPouts), 3),  # loose def'n
                          WHIP = round((H + BB) * 3/IPouts, 2),
                          KperBB = round(ifelse(yearID >= 1955,
                                                SO/(BB - IBB), SO/BB), 2))

    #####################
    # some simple queries
    #####################

    # Team pitching statistics, Toronto Blue Jays, 1993
    tor93 <- pitching %>%
               filter(yearID == 1993 & teamID == "TOR") %>%
               arrange(ERA)

    # Career pitching statistics, Greg Maddux
    subset(pitching, playerID == "maddugr01")

    # Best ERAs for starting pitchers post WWII
    pitching %>%
        filter(yearID >= 1946 & IPouts >= 600) %>%
        group_by(lgID) %>%
        arrange(ERA) %>%
        do(head(., 5))

    # Best K/BB ratios post-1955 among starters (excludes intentional walks)
    pitching %>%
        filter(yearID >= 1955 & IPouts >= 600) %>%
        mutate(KperBB = SO/(BB - IBB)) %>%
        arrange(desc(KperBB)) %>%
        head(., 10)

    # Best K/BB ratios among relievers post-1950 (min. 20 saves)
    pitching %>%
        filter(yearID >= 1950 & SV >= 20) %>%
        arrange(desc(KperBB)) %>%
        head(., 10)

    ###############################################
    # Winningest pitchers in each league each year:
    ###############################################

    # Add name & throws information:
    masterInfo <- Master %>%
                    select(playerID, nameLast, nameFirst, throws)

    # Merge masterInfo into the pitching data
    pitching1 <- right_join(masterInfo, pitching, by = "playerID")

    # Extract the pitcher with the maximum number of wins
    # each year, by league
    winp <- pitching1 %>%
             group_by(yearID, lgID) %>%
             filter(W == max(W)) %>%
             select(nameLast, nameFirst, teamID, W, throws)

    # A simple ANCOVA model of wins vs. year, league and hand (L/R)
    anova(lm(formula = W ~ yearID + I(yearID^2) + lgID + throws, data = winp))

    # Nature of managing pitching staffs has altered importance of
    # wins over time

    require("ggplot2")

    # compare loess smooth with quadratic fit
    ggplot(winp, aes(x = yearID, y = W)) +
        geom_point(aes(colour = throws, shape=lgID), size = 2) +
        geom_smooth(method="loess", size=1.5, color="blue") +
        geom_smooth(method = "lm", se=FALSE, color="black",
                     formula = y ~ poly(x,2)) +
        ylab("League maximum Wins") + xlab("Year") +
        ggtitle("Maximum pitcher wins by year")

    ## To reinforce this, plot the mean IPouts by year and league,
    ## which gives some idea of pitcher usage. Restrict pitcher
    ## pool to those who pitched at least 100 innings in a year.

    pitching %>% filter(IPouts >= 300) %>%  # >= 100 IP
    ggplot(., aes(x = yearID, y = IPouts, color = lgID)) +
      geom_smooth(method="loess") +
      labs(x = "Year", y = "IPouts")

    ## Another indicator: total number of complete games pitched
    ## (Mirrors the trend from the preceding plot.)

    pitching %>%
       group_by(yearID, lgID) %>%
       summarise(totalCG = sum(CG, na.rm = TRUE)) %>%
       ggplot(., aes(x = yearID, y = totalCG, color = lgID)) +
          geom_point() +
          geom_path() +
          labs(x = "Year", y = "Number of complete games")

[Package Lahman version 5.0-0 Index]