xFIP

Description

xFIP is a statistic that estimates a pitcher's expected run prevention independent of the performance of the defense.

Usage

1
xfip(flyballs, lgHRFB, BB, HBP, K, ip, year)

Arguments

flyballs

Fly balls allowed

lgHRFB

League HR/FB Percentage

BB

Balls Allowed

HBP

Hit By Pitches Allowed

K

Strikeouts

ip

Innings Pitched

year

Season

Details

xFIP is almost exactly like FIP, except it uses the expected number of home runs taking the pitcher's fly balls allowed times the league average home run per fly ball rate.

Value

Returns a numeric value equal to (13*(flyballs*lgHRFB)+(3*(BB+HBP))-(2*K))/(ip)+constant

Note

Innings Pitched (IP) is commonly reported with .1 indicating 1/3 of an inning and .2 indicating 2/3 of an inning. In order for this function to be accurate, please change the decimal to .333 for 1/3 of an inning and .666 for 2/3 of an inning.

Author(s)

Peter Xenopoulos

References

http://www.fangraphs.com/library/pitching/xfip/

See Also

fip,xfipminus

Examples

1
2
3
4
5
6
7
8
9
## The function is currently defined as
function (flyballs, lgHRFB, BB, HBP, K, ip, year) 
{
    constant <- linearWeights$cFIP[which(linearWeights$Season == 
        year)]
    xfip <- (13 * (flyballs * lgHRFB) + (3 * (BB + HBP)) - (2 * 
        K))/(ip) + constant
    return(xfip)
  }