These functions provide information about the power exponential
distribution with mean parameter equal to m, dispersion equal
to s, and family parameter equal to f: density,
cumulative distribution, quantiles, log hazard, and random generation.
The power exponential distribution has density
$$
f(y) = \frac{\exp(-(abs{y-\mu}/\sqrt{\sigma})^{2 \nu}/2)}{
\sqrt{\sigma} Gamma(1+1/(2 \nu)) 2^{1+1/(2 \nu)}}$$
where \(\mu\) is the mean of the distribution,
\(\sigma\) is the dispersion, and \(\nu\) is the family
parameter. \(\nu=1\) yields a normal distribution,
\(\nu=0.5\) a Laplace distribution, and
\(\nu=\infty\) a uniform distribution.