sim.qqnorm {animation} | R Documentation |
This demo shows the possible QQ plots created by random numbers generated from a Normal distribution so that users can get a rough idea about how QQ plots really look like.
sim.qqnorm(n = 20, last.plot = NULL, ...)
n |
integer: sample size |
last.plot |
an expression to be evaluated after the plot is drawn, e.g.
|
... |
other arguments passed to |
When the sample size is small, it is hard to get a correct inference about the distribution of data from a QQ plot. Even if the sample size is large, usually there are outliers far away from the straight line. Therefore, don't overinterpret the QQ plots.
NULL
Yihui Xie
oopt = ani.options(interval = 0.1, nmax = ifelse(interactive(), 100, 2)) par(mar = c(3, 3, 2, 0.5), mgp = c(1.5, 0.5, 0), tcl = -0.3) sim.qqnorm(n = 20, last.plot = expression(abline(0, 1))) ## HTML animation pages saveHTML({ par(mar = c(3, 3, 1, 0.5), mgp = c(1.5, 0.5, 0), tcl = -0.3) ani.options(interval = 0.1, nmax = ifelse(interactive(), 100, 2)) sim.qqnorm(n = 15, pch = 20, main = "") }, img.name = "sim.qqnorm", htmlfile = "sim.qqnorm.html", ani.height = 500, ani.width = 500, title = "Demonstration of Simulated QQ Plots", description = c("This animation shows the QQ plots of random numbers", "from a Normal distribution. Does them really look like normally", "distributed?")) ani.options(oopt)