The functions se_ig, re_ig, hce_ig, and ae_ig provide the Shannon entropy, Rényi entropy, Havrda and Charvat entropy, and Arimoto entropy, respectively, depending on the selected parametric values of the inverse-gamma distribution and \(\delta\).
Arguments
alpha
The strictly positive shape parameter of the inverse-gamma distribution (\(\alpha > 0\)).
beta
The strictly positive scale parameter of the inverse-gamma distribution (\(\beta > 0\)).
delta
The strictly positive parameter (\(\delta > 0\)) and (\(\delta \ne 1\)).
Author
Muhammad Imran, Christophe Chesneau and Farrukh Jamal
R implementation and documentation: Muhammad Imran <imranshakoor84@yahoo.com>, Christophe Chesneau <christophe.chesneau@unicaen.fr> and Farrukh Jamal farrukh.jamal@iub.edu.pk.
Details
The following is the probability density function of the inverse-gamma distribution:
$$
f(x)=\frac{\beta^{\alpha}}{\Gamma(\alpha)}x^{-\alpha-1}e^{-\frac{\beta}{x}},
$$
where \(x > 0\), \(\alpha > 0\) and \(\beta > 0\), and \(\Gamma(a)\) is the standard gamma function.
References
Rivera, P. A., Calderín-Ojeda, E., Gallardo, D. I., & Gómez, H. W. (2021). A compound class of the inverse Gamma and power series distributions. Symmetry, 13(8), 1328.
Glen, A. G. (2017). On the inverse gamma as a survival distribution. Computational Probability Applications, 15-30.