To calculate density function, distribution function, quantile function, and build data from random generator function
for the Jones Skew Exponential Power
The Jones Skew Exponential Power with parameters \(\mu\), \(\sigma\),\(\alpha\), and \(\beta\)
has density:
$$
f(y | \mu, \sigma, \alpha, \beta) = \left\{
\begin{array}{ll}
\frac{c}{\sigma} \exp\left(-|z|^{\alpha}\right), & \text{if } y < \mu \\
\frac{c}{\sigma} \exp\left(-|z|^{\beta}\right), & \text{if } y \geq \mu
\end{array}
\right.
$$
where:
$$z = \frac{y - \mu}{\sigma},$$
$$c = \left[ \Gamma(1 + \beta^{-1}) + \Gamma(1 + \alpha^{-1}) \right]^{-1}.$$
References
Rigby, R.A. and Stasinopoulos, M.D. and Heller, G.Z. and De Bastiani, F.
(2019) Distributions for Modeling Location, Scale,
and Shape: Using GAMLSS in R.CRC Press