data.big5 {sirt}R Documentation

Dataset Big 5 from qgraph Package

Description

This is a Big 5 dataset from the qgraph package (Dolan, Oorts, Stoel, Wicherts, 2009). It contains 500 subjects on 240 items.

Usage

data(data.big5)
data(data.big5.qgraph)

Format

Details

In these datasets, there exist 48 items for each dimension. The Big 5 dimensions are Neuroticism (N), Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C). Note that the data.big5 differs from data.big5.qgraph in a way that original items were recoded into three categories 0,1 and 2.

Source

See big5 in qgraph package.

References

Dolan, C. V., Oort, F. J., Stoel, R. D., & Wicherts, J. M. (2009). Testing measurement invariance in the target rotates multigroup exploratory factor model. Structural Equation Modeling, 16, 295-314.

Examples

## Not run: 
# list of needed packages for the following examples
packages <- scan(what="character")
     sirt   TAM   eRm   CDM   mirt  ltm   mokken  psychotools  psychomix
     psych

# load packages. make an installation if necessary
miceadds::library_install(packages)

#############################################################################
# EXAMPLE 1: Unidimensional models openness scale
#############################################################################

data(data.big5)
# extract first 10 openness items
items <- which( substring( colnames(data.big5), 1, 1 )=="O"  )[1:10]
dat <- data.big5[, items ]
I <- ncol(dat)
summary(dat)
  ##   > colnames(dat)
  ##    [1] "O3"  "O8"  "O13" "O18" "O23" "O28" "O33" "O38" "O43" "O48"
# descriptive statistics
psych::describe(dat)

#****************
# Model 1: Partial credit model
#****************

#-- M1a: rm.facets (in sirt)
m1a <- sirt::rm.facets( dat )
summary(m1a)

#-- M1b: tam.mml (in TAM)
m1b <- TAM::tam.mml( resp=dat )
summary(m1b)

#-- M1c: gdm (in CDM)
theta.k <- seq(-6,6,len=21)
m1c <- CDM::gdm( dat, irtmodel="1PL",theta.k=theta.k, skillspace="normal")
summary(m1c)
# compare results with loglinear skillspace
m1c2 <- CDM::gdm( dat, irtmodel="1PL",theta.k=theta.k, skillspace="loglinear")
summary(m1c2)

#-- M1d: PCM (in eRm)
m1d <- eRm::PCM( dat )
summary(m1d)

#-- M1e: gpcm (in ltm)
m1e <- ltm::gpcm( dat, constraint="1PL", control=list(verbose=TRUE))
summary(m1e)

#-- M1f: mirt (in mirt)
m1f <- mirt::mirt( dat, model=1, itemtype="1PL", verbose=TRUE)
summary(m1f)
coef(m1f)

#-- M1g: PCModel.fit (in psychotools)
mod1g <- psychotools::PCModel.fit(dat)
summary(mod1g)
plot(mod1g)

#****************
# Model 2: Generalized partial credit model
#****************

#-- M2a: rm.facets (in sirt)
m2a <- sirt::rm.facets( dat, est.a.item=TRUE)
summary(m2a)
# Note that in rm.facets the mean of item discriminations is fixed to 1

#-- M2b: tam.mml.2pl (in TAM)
m2b <- TAM::tam.mml.2pl( resp=dat, irtmodel="GPCM")
summary(m2b)

#-- M2c: gdm (in CDM)
m2c <- CDM::gdm( dat, irtmodel="2PL",theta.k=seq(-6,6,len=21),
                   skillspace="normal", standardized.latent=TRUE)
summary(m2c)

#-- M2d: gpcm (in ltm)
m2d <- ltm::gpcm( dat, control=list(verbose=TRUE))
summary(m2d)

#-- M2e: mirt (in mirt)
m2e <- mirt::mirt( dat, model=1,  itemtype="GPCM", verbose=TRUE)
summary(m2e)
coef(m2e)

#****************
# Model 3: Nonparametric item response model
#****************

#-- M3a: ISOP and ADISOP model - isop.poly (in sirt)
m3a <- sirt::isop.poly( dat )
summary(m3a)
plot(m3a)

#-- M3b: Mokken scale analysis (in mokken)
# Scalability coefficients
mokken::coefH(dat)
# Assumption of monotonicity
monotonicity.list <- mokken::check.monotonicity(dat)
summary(monotonicity.list)
plot(monotonicity.list)
# Assumption of non-intersecting ISRFs using method restscore
restscore.list <- mokken::check.restscore(dat)
summary(restscore.list)
plot(restscore.list)

#****************
# Model 4: Graded response model
#****************

#-- M4a: mirt (in mirt)
m4a <- mirt::mirt( dat, model=1,  itemtype="graded", verbose=TRUE)
print(m4a)
mirt.wrapper.coef(m4a)

#----  M4b: WLSMV estimation with cfa (in lavaan)
lavmodel <- "F=~ O3__O48
             F ~~ 1*F
                "
# transform lavaan syntax with lavaanify.IRT
lavmodel <- TAM::lavaanify.IRT( lavmodel, items=colnames(dat) )$lavaan.syntax
mod4b <- lavaan::cfa( data=as.data.frame(dat), model=lavmodel, std.lv=TRUE,
                 ordered=colnames(dat),  parameterization="theta")
summary(mod4b, standardized=TRUE, fit.measures=TRUE, rsquare=TRUE)
coef(mod4b)

#****************
# Model 5: Normally distributed residuals
#****************

#----  M5a: cfa (in lavaan)
lavmodel <- "F=~ O3__O48
             F ~~ 1*F
             F ~ 0*1
             O3__O48 ~ 1
                "
lavmodel <- TAM::lavaanify.IRT( lavmodel, items=colnames(dat) )$lavaan.syntax
mod5a <- lavaan::cfa( data=as.data.frame(dat), model=lavmodel, std.lv=TRUE,
                 estimator="MLR" )
summary(mod5a, standardized=TRUE, fit.measures=TRUE, rsquare=TRUE)

#----  M5b: mirt (in mirt)

# create user defined function
name <- 'normal'
par <- c("d"=1, "a1"=0.8, "vy"=1)
est <- c(TRUE, TRUE,FALSE)
P.normal <- function(par,Theta,ncat){
     d <- par[1]
     a1 <- par[2]
     vy <- par[3]
     psi <- vy - a1^2
     # expected values given Theta
     mui <- a1*Theta[,1] + d
     TP <- nrow(Theta)
     probs <- matrix( NA, nrow=TP, ncol=ncat )
     eps <- .01
     for (cc in 1:ncat){
        probs[,cc] <- stats::dnorm( cc, mean=mui, sd=sqrt( abs( psi + eps) ) )
                    }
     psum <- matrix( rep(rowSums( probs ),each=ncat), nrow=TP, ncol=ncat, byrow=TRUE)
     probs <- probs / psum
     return(probs)
}

# create item response function
normal <- mirt::createItem(name, par=par, est=est, P=P.normal)
customItems <- list("normal"=normal)
itemtype <- rep( "normal",I)
# define parameters to be estimated
mod5b.pars <- mirt::mirt(dat, 1, itemtype=itemtype,
                   customItems=customItems, pars="values")
ind <- which( mod5b.pars$name=="vy")
vy <- apply( dat, 2, var, na.rm=TRUE )
mod5b.pars[ ind, "value" ] <- vy
ind <- which( mod5b.pars$name=="a1")
mod5b.pars[ ind, "value" ] <- .5* sqrt(vy)
ind <- which( mod5b.pars$name=="d")
mod5b.pars[ ind, "value" ] <- colMeans( dat, na.rm=TRUE )

# estimate model
mod5b <- mirt::mirt(dat, 1, itemtype=itemtype, customItems=customItems,
                 pars=mod5b.pars, verbose=TRUE    )
sirt::mirt.wrapper.coef(mod5b)$coef

# some item plots
    par(ask=TRUE)
plot(mod5b, type='trace', layout=c(1,1))
    par(ask=FALSE)
# Alternatively:
sirt::mirt.wrapper.itemplot(mod5b)

## End(Not run)

[Package sirt version 4.1-15 Index]