[R] Tukey.aov with split-plot designs
Peter B. Mandeville
mandevip at uaslp.mx
Wed Jul 5 08:29:58 CEST 2000
I am using R 1.1 with Redhat 6.2 and RW 1.001 with Win98 (the upkey doesn't
work on my IBM either as has been previously reported by others).
The function aov doesn't return either the residuals or the residual
degrees of freedom for split-plot designs.
If you use the following code from Baron and Li's "Notes on the use of R
for psycology experiments and questionnaires"
data <- c(30,14,24,38,26,28,18,20,34,28,16,10,18,20,14,34,22,30,44,30)
res0 <- aov(rt~drug,data=Stv.df)
res1 <- aov(rt~drug+subj,data=Stv.df)
res2 <- aov(rt~drug+Error(subj/drug),data=Stv.df)
res2$resid doesn't work and reports NULL
resid(res2) doesn't work and reports NULL
res2$df.residual doesn't work and reports NULL
Is this an undocumented feature or an error?
It sure plays havoc with Dr. Bates' contribution of Tukey.aov which works
with res0 and res1 but doesn't work with res2 and reports
Error in qtukey(p, nranges, nmeans, df, lower.tail, log.p) :
Non-numeric argument to mathematical function
A simple but inelegant workaround is to input mse and df.residual as
function arguments in addition to the aov object. Does anyone have a better
Peter B. Mandeville mandevip at deimos.tc.uaslp.mx
Jefe del Depto. de Informática y Bioestadística rpe1531 at pasteur.fmed.uaslp.mx
Facultad de Medicine Tel: 48 26-23-45 ext. 232
Universidad Autónoma de San Luis Potosí Fax: 48 28-23-52
Av. V. Carranza 2405
Col. Los Filtros
Apartado Postal 145
San Luis Potosí, S.L.P.
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch
More information about the R-help