Prior to the steps below, enter the data as appropriate for the analyses (described elsewhere). As always, the following commands should be typed directly in the R console window.
Reformat the data from wide format to long format for analysis.
Subject <- factor(rep(1:4, times = 2))
Time <- factor(rep(c("Time1", "Time2"), each = 4))
Outcome <- c(Outcome1, Outcome2)
RepeatedDataLong <- data.frame(Subject, Time, Outcome)
Get the sample sizes, means, and standard deviations for the variables.
Results <- aov(Outcome ~ Time + Error(Subject / Time))
model.tables(Results, "means")
lapply(
split(Outcome, Time),
function(x) c(n = length(x), mean = mean(x), sd = sd(x))
)
Get the ANOVA source table with tests of statistical significance.
summary(Results)