###########################################################################
# logit #
# #
# The logit function is the inverse of the sigmoid or logistic function, #
# and transforms a continuous value (usually probability p) in the #
# interval [0,1] to the real line (where it usually is the logarithm of #
# the odds). The invlogit function (called either the inverse logit or #
# the logistic function) transforms a real number (usually the logarithm #
# of the odds) to a value (usually probability p) in the interval [0,1]. #
# If p is a probability, then p/(1-p) is the corresponding odds, while #
# logit of p is the logarithm of the odds. The difference between the #
# logits of two probabilities is the logarithm of the odds ratio. The #
# derivative of probability p in a logistic function is: #
# (d / dx) = p * (1 - p). #
###########################################################################
invlogit <- function(x)
{
InvLogit <- 1 / {1 + exp(-x)}
return(InvLogit)
}
logit <- function(p)
{
if({any(p < 0)} || {any(p > 1)}) stop("p must be in [0,1].")
Logit <- log(p / {1 - p})
return(Logit)
}
#End
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.