yates.effects {dae} | R Documentation |
Extracts Yates effects from an aov
object or aovlist
object.
yates.effects(aov.obj, error.term="Within", data=NULL)
aov.obj |
An |
error.term |
The term from the |
data |
A |
Yates effects are specific to 2^k
experiments, where Yates
effects are conventionally defined as the difference between the upper
and lower levels of a factor. We follow the convention used in
Box, Hunter and Hunter (1978) for scaling of higher order interactions:
all the Yates effects are on the same scale, and represent the average
difference due to the interaction between two different levels.
Effects are estimated only from the error term supplied to the
error.term
argument.
A vector
of the Yates effects.
Chris Brien
qqyeffects
in package dae, aov
.
## analysis of 2^4 factorial experiment from Table 10.6 of Box, Hunter and
## Hunter (1978) Statistics for Experimenters. New York, Wiley.
## use ?Fac4Proc.dat for data set details
data(Fac4Proc.dat)
Fac4Proc.aov <- aov(Conv ~ Catal * Temp * Press * Conc + Error(Runs),
Fac4Proc.dat)
round(yates.effects(Fac4Proc.aov, error.term="Runs", data=Fac4Proc.dat), 2)