One of my readers asked two weeks ago how to control two graphics windows with the slider in gWidgets. Here is a simple example: if (!require("gWidgetsRGtk2")) install.packages("gWidgetsRGtk2") library(gWidgetsRGtk2) options(guiToolkit = "RGtk2") graphics.off() x11() x11() dev.set() gslider(from = 1, to = 100, value = 10,     container = gwindow("Two Plotting Windows"), ... [Read more...]

It is not uncommon to see messy R code which is almost not human-readable like this: # rotation of the word "Animation" # in a loop; change the angle and color # step by step for (i in 1:360) { # redraw the plot again and again plot(1,ann=FALSE,type="n",axes=FALSE) # rotate; use ... [Read more...]

e know the real distribution of the F statistic in linear models — it is a non-central F distribution. Under H0, we have a central F distribution. Given 1 – α, we can compute the probability of (correctly) rejecting H0. I created a simple demo to illustrate how the power changes as other parameters ... [Read more...]