QuadraticEstimatingEquations/R/a.Crowder.R

# First weighting vector of the quadratic estimating equation (Crowder)
# 
# Author: Francois Pelletier
#
# LGPL-3.0
###############################################################################

#' First weighting vector of the quadratic estimating equation (Crowder)
#' 
#' @param param Vector of parameters of the distribution function
#' @param variancef Variance function of the distribution
#' @param skewnessf Skewness function of the distribution
#' @param kurtosisf Kurtosis function of the distribution
#' @param dmean Derivative in respect to the parameter vector of the mean function of the distribution
#' @param dsd Derivative in respect to the parameter vector of the standard deviation function of the distribution
#' @return First weighting vector
#' @export a.Crowder
#' @author Francois Pelletier
a.Crowder <- function(param,variancef,skewnessf,kurtosisf,dmean,dsd)
{
	(-(kurtosisf(param)+2)*dmean(param)+
				2*skewnessf(param)*dsd(param))/
			(variancef(param)*gammaf.Crowder(param,skewnessf,kurtosisf))
}