Agents to stimulate cellular differentiation
In a biomedical study of the immuno-activating ability of two agents, TNF (tumor necrosis factor) and IFN (interferon), to induce cell differentiation, the number of cells that exhibited markers of differentiation after exposure to TNF and IFN was recorded. At each of the 16 dose combinations of TNF/INF, 200 cells were examined. The main question is whether the two agents stimulate cell differentiation synergistically or independently.
data(cellular)
A data frame with 16 rows and 3 variables:
a numeric vector giving the number of cells that exhibited markers of differentiation after exposure to the dose of the two agents
a numeric vector giving the dose (U/ml) of TNF
a numeric vector giving the dose (U/ml) of IFN
Piegorsch W.W., Weinberg C.R. and Margolin B.H. (1988) Exploring simple independent action in multifactor tables of proportions. Biometrics 44, 595-603.
Vanegas L.H. and Rondon L.M. (2020) A data transformation to deal with constant under/over-dispersion in binomial and poisson regression models. Journal of Statistical Computation and Simulation 90, 1811-1833.
barplot(100*cells/200 ~ ifn + tnf, beside=TRUE, data=cellular, col=terrain.colors(4),
xlab="Dose of TNF", ylab="% of cells with markers of differentiation")
legend(0, 100, c("0","4","20","100"), col=terrain.colors(4), bty="n", cex=0.9,
title="Dose of IFN", y.intersp=0.1, x.intersp=0.3, title.adj=0.2, pch=15)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.