hyperbPi: Value of the parameter pi of the hyperbolic distribution.
zeta: Value of the parameter zeta of the hyperbolic distribution.
lambda: Parameter related to order of Bessel functions.
Returns
The functions RLambda and SLambda are used in the calculation of the mean and variance. They are functions of the Bessel functions of the third kind, implemented in as besselK. The other functions are used in calculation of higher moments. See Barndorff-Nielsen, O. and , P. (1981) for details of the calculations.
The parameterization of the hyperbolic distribution used for this and other components of the HyperbolicDist package is the (pi,zeta) one. See hyperbChangePars to transfer between parameterizations.
References
Barndorff-Nielsen, O. and , P (1981). Hyperbolic distributions and ramifications: contributions to theory and application. In Statistical Distributions in Scientific Work, eds., Taillie, C., Patil, G. P., and Baldessari, B. A., Vol. 4, pp. 19--44. Dordrecht: Reidel.
Barndorff-Nielsen, O. and , P (1983). Hyperbolic distributions. In Encyclopedia of Statistical Sciences, eds., Johnson, N. L., Kotz, S. and Read, C. B., Vol. 3, pp. 700--707. New York: Wiley.