Toxicological Study on Female Wistar Rats
ASAT-Values for a new compound and a control group of 34 female Wistar rats.
data(ASAT)
A data frame with 34 observations on the following 2 variables.
the ASAT-values (a liver enzyme)
a factor with levels Compound and Control.
The aim of this toxicological study is the proof of safety for the new compound. The data are originally given in Hothorn (1992) and reproduced in Hauschke et al. (1999).
Ludwig A. Hothorn (1992), Biometrische Analyse toxikologischer Untersuchungen. In: J. Adams (ed.): Statistisches Know how in der medizinischen Forschung. Ullstein-Mosby, Berlin, 475–590.
Dieter Hauschke, Meinhard Kieser & Ludwig A. Hothorn (1999), Proof of safety in toxicology based on the ratio of two means for normally distributed data. Biometrical Journal, 41(3), 295–304.
Rafael Pfl\"uger & Torsten Hothorn (2002), Assessing Equivalence Tests with Respect to their Expected $p$-Value. Biometrical Journal, 44(8), 1002–1027.
data(ASAT)
# does not really look symmetric
plot(asat ~ group, data=ASAT)
# proof-of-safety based on ration of medians
pos <- wilcox.exact(I(log(asat)) ~ group, data = ASAT, alternative = "less",
conf.int=TRUE)
# one-sided confidence set. Safety cannot be concluded since the effect of
# the compound exceeds 20% of the control median
exp(pos$conf.int)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.