nlCheckPars {NormalLaplace}

Check Parameters of the Normal Laplace Distribution

Description

Given a set of parameters for the normal Laplace distribution, the functions checks the validity of each parameter and if they and if they correspond to the boundary cases.

Usage

nlCheckPars(param)

Arguments

param

Numeric. Parameter values for the normal Laplace distribution.

Details

The vector param takes the form c(mu, sigma, alpha, beta).

If any of sigma, alpha or beta is negative or NA, an error is returned.

Author(s)

David Scott [e-mail], Simon Potter

References

William J. Reed. (2006) The Normal-Laplace Distribution and Its Relatives. In Advances in Distribution Theory, Order Statistics and Inference, pp. 61–74. Birkhäuser, Boston.

Examples

## Correct parameters
nlCheckPars(c(0, 1.5, 1, 2))
nlCheckPars(c(3, 1, 1.5, 2))

## Incorrect parameters, each error providing a different error message
nlCheckPars(c(2, -1, 1, 1))          # invalid sigma
nlCheckPars(c(2, 1, -1, 2))          # invalid alpha
nlCheckPars(c(0, 1, 2, -1))          # invalid beta
nlCheckPars(c(0, -0.01, -0.1, 1))    # sigma and alpha incorrect
nlCheckPars(c(2, -0.5, 1, -0.2))     # sigma and beta incorrect
nlCheckPars(c(1, 1, -0.2, -1))       # alpha and beta incorrect
nlCheckPars(c(0, -0.1, -0.2, -0.3))  # all three parameters erroneous
nlCheckPars(c(0.5, NA, 1, 1))        # NA introduced
nlCheckPars(c(-1, 1, 1))             # incorrect number of parameters