tukey: Multiple comparison: Tukey's test

In ExpDes: Experimental Designs Package

Description

tukey Performs the test of Tukey, for multiple comparison of means.

Usage

tukey(y, trt, DFerror, SSerror, alpha = 0.05, group = TRUE, main = NULL)

Arguments

y	Numeric or complex vector containing the response variable.
trt	Numeric or complex vector containing the treatments.
DFerror	Error degrees of freedom.
SSerror	Error sum of squares.
alpha	Significance level.
group	TRUE or FALSE.
main	Title.

Details

It is necessary first makes a analysis of variance.

Value

y Numeric trt factor DFerror Numeric MSerror Numeric alpha Numeric group Logic main Text

Author(s)

Eric B Ferreira, [e-mail]

Denismar Alves Nogueira

Portya Piscitelli Cavalcanti (Adapted from Felipe de Mendiburu - GPL)

References

Principles and procedures of statistics a biometrical approach Steel and Torry and Dickey. Third Edition 1997

See Also

scottknott, duncan, lsd, lsdb, ccboot, snk, ccF.

Examples

data(ex1)
attach(ex1)
crd(trat, ig, quali = TRUE, mcomp = "tukey", sigT = 0.05)

Example output

Attaching package: ‘ExpDes’

The following object is masked from ‘package:stats’:

    ccf

------------------------------------------------------------------------
Analysis of Variance Table
------------------------------------------------------------------------
           DF     SS MS     Fc     Pr>Fc
Treatament  3 214.88  3 6.5212 0.0029622
Residuals  20 219.67  2                 
Total      23 434.55  1                 
------------------------------------------------------------------------
CV = 3.41 %

------------------------------------------------------------------------
Shapiro-Wilk normality test
p-value:  0.91697 
According to Shapiro-Wilk normality test at 5% of significance, residuals can be considered normal.
------------------------------------------------------------------------

------------------------------------------------------------------------
Homogeneity of variances test
p-value:  0.1863216 
According to the test of bartlett at 5% of significance, residuals can be considered homocedastic.
------------------------------------------------------------------------

Tukey's test
------------------------------------------------------------------------
Groups Treatments Means
a 	 0 	 102.1983 
 b 	 10 	 96.74333 
 b 	 5 	 95.05833 
 b 	 15 	 94.74333 
------------------------------------------------------------------------

ExpDes documentation built on Oct. 5, 2021, 9:09 a.m.