Computes the Sortino ratio for a given ditribution
sortinog(spec, alpha, a, b, ...)
a character string specifying the distribution (for example, "norm" corresponds to the standard normal)
a real valued parameter, see Chan and Nadarajah for details
the lower end point of the distribution specified by spec
the upper end point of the distribution specified by spec
other parameters
An object of the same length as alpha
, giving the Sortino ratio of the distribution specified by spec
S. Chan and S. Nadarajah, Risk: An R package for risk measures, submitted
T. Rollinger and S. Hoffman, Sortino ratio: A better measure of risk, Risk Management, 40-42, 2013