inibestcubecov {CUB} R Documentation

## Preliminary parameter estimates for CUBE models with covariates

### Description

Compute preliminary parameter estimates for a CUBE model with covariates for all the three parameters. These estimates are set as initial values to start the E-M algorithm within maximum likelihood estimation.

### Usage

```inibestcubecov(m,ordinal,Y,W,Z)
```

### Arguments

 `m` Number of ordinal categories `ordinal` Vector of ordinal responses `Y` Matrix of selected covariates to explain the uncertainty parameter `W` Matrix of selected covariates to explain the feeling parameter `Z` Matrix of selected covariates to explain the overdispersion parameter

### Value

A vector `(inibet, inigama, inialpha)` of preliminary estimates of parameter vectors for π = π(\bold{β}), ξ=ξ(\bold{γ}), φ=φ(\bold{α}), respectively, of a CUBE model with covariates for all the three parameters. In details, `inibet`, `inigama` and `inialpha` have length equal to NCOL(Y)+1, NCOL(W)+1 and NCOL(Z)+1, respectively, to account for an intercept term for each component.

`inibestcube`, `inibestcubecsi`, `inibestgama`

### Examples

```data(relgoods)
m<-10
naord<-which(is.na(relgoods\$Tv))
nacovpai<-which(is.na(relgoods\$Gender))
nacovcsi<-which(is.na(relgoods\$year.12))
nacovphi<-which(is.na(relgoods\$EducationDegree))
na<-union(union(naord,nacovpai),union(nacovcsi,nacovphi))
ordinal<-relgoods\$Tv[-na]
Y<-relgoods\$Gender[-na]
W<-relgoods\$year.12[-na]
Z<-relgoods\$EducationDegree[-na]
ini<-inibestcubecov(m,ordinal,Y,W,Z)
p<-NCOL(Y)
q<-NCOL(W)
inibet<-ini[1:(p+1)]               # Preliminary estimates for uncertainty
inigama<-ini[(p+2):(p+q+2)]        # Preliminary estimates for feeling
inialpha<-ini[(p+q+3):length(ini)] # Preliminary estimates for overdispersion
```

[Package CUB version 1.1.4 Index]