# NOT RUN {
# Example: the birthwt data set from the MASS library
# We want to find variables associated with low birth weight
library(MASS)
fullfit <- glm(low~age+lwt+race+smoke+ptl+ht+ui+ftv, family=binomial, data=birthwt)
hypotheses <- c("age", "lwt", "race", "smoke", "ptl", "ht", "ui", "ftv")
# Define the local test to be used in the closed testing procedure
mytest <- function(hyps) {
others <- setdiff(hypotheses, hyps)
form <- formula(paste(c("low~", paste(c("1", others), collapse="+"))))
anov <- anova(glm(form, data=birthwt, family=binomial), fullfit, test="Chisq")
res <- anov$"Pr("[2] # for R >= 2.14.0
if (is.null(res)) res <- anov$"P("[2] # earlier versions
res
}
# perform the closed testing procedure
cl <- closed(mytest, hypotheses)
summary(cl)
defining(cl)
shortlist(cl)
hypotheses(cl)
# how many variables among a chosen set are associated with the response?
pick(cl, c("ht", "lwt", "smoke", "ui"))
# }
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