MQIF: Function of a Quadratic Inference Function (QIF) Model

In marlod: Marginal Modeling for Exposure Data with Values Below the LOD

Function of a Quadratic Inference Function (QIF) Model

Description

The function is used to calculate a empirical MSE minimization criterion (EMMC) value in the "Selected.QIF" function.

Usage

MQIF(id, y, x, lod, substitue, corstr, beta, typetd, maxiter)

Arguments

id	A column matrix of subject IDs. The number of rows is the total number of observations. Data must be sorted by IDs.
y	A column matrix of the observed outcome values or responses.
x	A matrix of covariate values, for which the number of columns is the number of covariates.
lod	A numeric value of limit of detection (LOD).
substitue	A character string specifying the substitution approach, including "None", "LOD", "LOD2", "LODS2", "BetaMean", "BetaGM", "MIWithID", "MIWithIDRM", and "QQplot".
corstr	A character string specifying the working correlation structure, given by either "exchangeable" or "AR-1".
beta	A matrix of initial parameter estimates, e.g., these estimates could be from general linear model or generalized estimating equation (GEE) using independence working structure.
typetd	An atomic vector specifying the types of time-dependent covaraites. The length of this vector is the number of regression paramenters, including the intercept. "1" is assigned to any time-indepednet covariates or covariates in a cluster study.
maxiter	The maximum number of iterations.

Value

An object of class "MQIF".

marlod documentation built on June 8, 2025, 10:32 a.m.