DD_weight_1 {Opt5PL}

The first derivative of the Ds-optimality criterion with respect to the model parameters

Description

The first derivative of the Ds-optimality criterion with respect to the model parameters. This is a sub-function of D_weight to run one iteration of Newton-Raphson method.

Usage

DD_weight_1(W, T, X, inv, inv1, order)

Arguments

W

A numeric vector. The first K-1 weights for a given design

T

A numeric vector. Model parameter values for the 5PL model

X

A numeric vector. K dose levels for a given design

inv

A numeric matrix. Inverse information matrix for the 5PL model

inv1

A numeric matrix. Inverse information matrix for the 4PL model

order

numeric. The number of model paraemters