group.UCL {Rmisc}

Group Upper-Center-Lower

Description

Applies a function which calculates a parameter with lower/uper bounds to groups of data.

Usage

  group.UCL(x, data, FUN, ...)

Arguments

x

an 'aggregate' compatible formula

data

a data frame (or list) from which the variables in formula should be taken.

FUN

the function to apply to each group

...

extra params passed on to aggregate

Value

A data frame consisting of one column for each grouping factor plus three columns for the upper bound, mean and lower bound of the standard error interval for each level of the grouping factor.

Examples

require(latticeExtra)
with(group.UCL(weight~feed,chickwts,FUN=CI),
 segplot(feed~weight.lower+weight.upper,center=weight.mean)
)

require(Hmisc)
with(group.UCL(Temp~Month,airquality,FUN=STDERR),
 xYplot(Cbind(Temp.mean,Temp.lower,Temp.upper)~numericScale(Month),type="b",ylim=c(60,90))
)