| scheffe.test {agricolae} | R Documentation |
Scheffe 1959, method is very general in that all possible contrasts can be tested for significance and confidence intervals can be constructed for the corresponding linear. The test is conservative.
scheffe.test(y, trt, DFerror, MSerror, Fc, alpha = 0.05, group=TRUE, main = NULL, console=FALSE )
y |
model(aov or lm) or answer of the experimental unit |
trt |
Constant( only y=model) or vector treatment applied to each experimental unit |
DFerror |
Degrees of freedom |
MSerror |
Mean Square Error |
Fc |
F Value |
alpha |
Significant level |
group |
TRUE or FALSE |
main |
Title |
console |
logical, print output |
It is necessary first makes a analysis of variance.
y |
class (aov or lm) or vector numeric |
trt |
constant (only y=model) or vector alfanumeric |
DFerror |
Numeric |
MSerror |
Numeric |
Fc |
Numeric |
alpha |
Numeric |
group |
Logic |
main |
Text |
Felipe de Mendiburu
Robert O. Kuehl. 2nd ed. Design of experiments. Duxbury, copyright 2000. Steel, R.; Torri,J; Dickey, D.(1997) Principles and Procedures of Statistics A Biometrical Approach. pp189
HSD.test, LSD.test, SNK.test ,
bar.err, bar.group,duncan.test
library(agricolae) data(sweetpotato) model<-aov(yield~virus, data=sweetpotato) comparison <- scheffe.test(model,"virus", group=TRUE,console=TRUE, main="Yield of sweetpotato\nDealt with different virus") # Old version scheffe.test() df<-df.residual(model) MSerror<-deviance(model)/df Fc<-anova(model)["virus",4] comparison <- with(sweetpotato,scheffe.test(yield, virus, df, MSerror, Fc, group=TRUE,main="Yield of sweetpotato. Dealt with different virus"))