estimateSE: Standard Error of Ability Parameter Estimate

Description

Estimates the standard error for a respondent's ability parameter estimate, \(\theta\).

Usage

estimateSE(catObj)

Arguments

catObj

An object of class Cat

Value

The function estimateSE returns a numeric for the standard error for \(\theta\).

Details

The function estimateSE estimates the standard error of the ability estimate given the estimation approach of the Cat object, specified in estimation slot of Cat object.

The expected a posteriori approach is used when estimation slot is "EAP". This method involves integration. See Note for more information.

The modal a posteriori approach is used when estimation slot is "MAP". This method is only available using the normal prior distribution.

The maximum likelihood approach is used when estimation slot is "MLE". When the likelihood of the ability estimate is undefined, the MAP or EAP method will be used, determined by what is specified in the estimationDefault slot in Cat object.

The weighted maximum likelihood approach is used when estimation slot is "WLE". Estimating \(\theta\) requires root finding with the ``Brent'' method in the GNU Scientific Library (GSL) with initial search interval of [-5,5].

Examples

Run this code

# NOT RUN {
## Loading ltm Cat object
data(ltm_cat)

## Store example answers
setAnswers(ltm_cat) <- c(1,0,1,0,1, rep(NA, 35))

## Set different estimation procedures and calculate ability estimate and its standard error
setEstimation(ltm_cat) <- "EAP"
estimateTheta(ltm_cat)
estimateSE(ltm_cat)

setEstimation(ltm_cat) <- "MAP"
estimateTheta(ltm_cat)
estimateSE(ltm_cat)

setEstimation(ltm_cat) <- "MLE"
estimateTheta(ltm_cat)
estimateSE(ltm_cat)

setEstimation(ltm_cat) <- "WLE"
estimateTheta(ltm_cat)
estimateSE(ltm_cat)


# }