tapply.stat {agricolae} | R Documentation

## Statistics of data grouped by factors

### Description

This process lies in finding statistics which consist of more than one variable, grouped or crossed by factors. The table must be organized by columns between variables and factors.

### Usage

    tapply.stat(y, x, stat = "mean")

### Arguments

`y` | data.frame variables
`x` | data.frame factors
`stat` | Method

### Value

Statistics of quantitative variables by categorical variables.

### Author(s)

Felipe de Mendiburu

### Examples

    library(agricolae)
    # case of 1 single factor
    data(sweetpotato)
    tapply.stat(sweetpotato[,2],sweetpotato[,1],mean)
    with(sweetpotato,tapply.stat(yield,virus,sd))
    with(sweetpotato,tapply.stat(yield,virus,function(x) max(x)-min(x)))
    with(sweetpotato,tapply.stat(yield,virus,
    function(x) quantile(x,0.75,6)-quantile(x,0.25,6)))
    # other case
    data(cotton)
    with(cotton,tapply.stat(yield,cotton[,c(1,3,4)],mean))
    with(cotton,tapply.stat(yield,cotton[,c(1,4)],max))
    # Height of pijuayo
    data(growth)
    with(growth,tapply.stat(height, growth[,2:1], function(x) mean(x,na.rm=TRUE)))

[Package agricolae version 1.2-9 Index]