rat.brain {WWGbook} | R Documentation |
The data used in this example were originally reported by Douglas, et al. (2004). The aim of their experiment was to examine nucleotide activation (guanine nucleotide bonding) in seven different brain nuclei (i.e., brain regions) among five adult male rats.
data(rat.brain)
A data frame with 30 observations on the following 4 variables.
Douglas, C.L., Demarco, G.J., Baghdoyan, H.A., and Lydic, R, Pontine and basal forebrain cholinergic interaction: implications for sleep and breathing, Respiratory Physiology and Neurobiology, 143, 251, 2004.
West, B., Welch, K. & Galecki, A, Linear Mixed Models: A Practical Guide Using Statistical Software, Chapman Hall / CRC Press, first edition, 2006.
attach(rat.brain) ###Figure 5.1: Line graphs of activation for each animal by region within levels of treatment for the Rat Brain data. region.f <- region region.f[region == 1] <- 1 region.f[region == 2] <- 2 region.f[region == 3] <- 0 region.f <- factor(region.f) treat <- treatment treat[treatment == 1] <- 0 treat[treatment == 2] <- 1 treat <- factor(treat) rat.brain <- data.frame(rat.brain, region.f, treat) library(lattice) # Load the library for trellis graphics. # Load the nlme library, which is required for the # plots below as well as for subsequent models. library(nlme) rat.brain.g1 <- groupedData(activate ~ region | animal, outer = ~ treat, data = rat.brain) plot(rat.brain.g1, display = "animal", outer = TRUE, aspect = 2, key = FALSE, xlab = "region", ylab = "mean activate", main="Treatment" )