purka.mle: MLE of the Purkayashta distribution

In Directional: A Collection of Functions for Directional Data Analysis

MLE of the Purkayashta distribution

Description

MLE of the Purkayashta distribution.

Usage

purka.mle(x, tol = 1e-07)

Arguments

x	A numerical vector with data expressed in radians or a matrix with spherical data.
tol	The tolerance value to terminate the Brent algorithm.

Details

MLE of the Purkayastha distribution is performed.

Value

A list including:

theta	The median direction.
circtheta	In case of circular data the circular mean is also returned.
alpha	The concentration parameter.
loglik	The log-likelihood.
alpha.sd	The standard error of the concentration parameter.

Author(s)

Michail Tsagris.

R implementation and documentation: Michail Tsagris [e-mail].

References

Purkayastha S. (1991). A Rotationally Symmetric Directional Distribution: Obtained through Maximum Likelihood Characterization. The Indian Journal of Statistics, Series A, 53(1): 70–83.

Cabrera J. and Watson G. S. (1990). On a spherical median related distribution. Communications in Statistics-Theory and Methods, 19(6): 1973–1986.

See Also

circ.cor1

Examples

x <- cbind( rnorm(100,1,1), rnorm(100, 2, 1) )
x <- x / sqrt(rowSums(x^2))
purka.mle(x)

Directional documentation built on Oct. 12, 2023, 1:07 a.m.