Skew Student-t distribution parameter estimation

Fits the parameters of the skew Student-t distribution.

Usage

sstdFit(x, ...)

Arguments

x: a numeric vector of quantiles.
...: parameters passed to the optimization function nlm.

Value

sstdFit returns a list with the following components:

par: The best set of parameters found.
objective: The value of objective corresponding to par.
convergence: An integer code. 0 indicates successful convergence.
message: A character string giving any additional information returned by the optimizer, or NULL. For details, see PORT documentation.
iterations: Number of iterations performed.
evaluations: Number of objective function and gradient function evaluations.

References

Fernandez C., Steel M.F.J. (2000); On Bayesian Modelling of Fat Tails and Skewness, Preprint, 31 pages.

Author

Diethelm Wuertz for the Rmetrics R-port

Examples

## sstd -
   set.seed(1953)
   r = rsstd(n = 1000)

       
## sstdFit -
   sstdFit(r)
#> $minimum
#> [1] 1306.033
#> 
#> $estimate
#>        mean          sd          nu          xi 
#> -0.01376393  1.00314970  4.21091043  1.37308787 
#> 
#> $gradient
#>          mean            sd            nu            xi 
#>  5.691163e-04  3.685488e-04  3.012995e-05 -1.286657e-04 
#> 
#> $code
#> [1] 1
#> 
#> $iterations
#> [1] 18
#>