ABSTRACT
Summary statistics such as mean, standard deviation, variance, minimum, maximum, and range are derived in quite a few R functions, commonly as a parameter or a sub-function. Functions commonly used in R books for quickly creating a lot of numbers to display are those that generate pseudorandom numbers. A common need in environmental research is to compare samples of a phenomenon or compare samples with an assumed standard population. The purpose of analysis of variance is to compare groups based upon continuous variables. It can be thought of as an extension of a t test where we have more than two groups, or as a linear model where one variable is a factor.
