Abstract

Comparison of the parameters of the items estimated according to Partial and Generalized Partial Credit Models: a simulation study By: Osama AbdulAziz Alwusaidi

Contents

Basic descriptive statistics

summary(Data_OAlwusaidi_GPCM)
##      Item01          Item02         Item03          Item04     
##  Min.   :0.000   Min.   :0.00   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:1.00   1st Qu.:1.000   1st Qu.:1.000  
##  Median :2.000   Median :2.00   Median :2.000   Median :2.000  
##  Mean   :2.082   Mean   :1.94   Mean   :2.151   Mean   :2.305  
##  3rd Qu.:3.000   3rd Qu.:3.00   3rd Qu.:3.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.00   Max.   :4.000   Max.   :4.000  
##      Item05          Item06          Item07          Item08    
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.00  
##  1st Qu.:2.000   1st Qu.:1.000   1st Qu.:1.000   1st Qu.:1.00  
##  Median :2.000   Median :2.000   Median :2.000   Median :1.00  
##  Mean   :2.409   Mean   :2.019   Mean   :1.937   Mean   :1.38  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:2.00  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.00  
##      Item09         Item10          Item11          Item12     
##  Min.   :0.00   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.00   1st Qu.:1.000   1st Qu.:1.000   1st Qu.:0.000  
##  Median :2.00   Median :3.000   Median :2.000   Median :1.000  
##  Mean   :1.99   Mean   :2.389   Mean   :2.074   Mean   :1.578  
##  3rd Qu.:3.00   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000  
##  Max.   :4.00   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item13          Item14          Item15          Item16     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:2.000   1st Qu.:1.000   1st Qu.:1.000   1st Qu.:0.000  
##  Median :2.000   Median :2.000   Median :2.000   Median :1.000  
##  Mean   :2.462   Mean   :1.836   Mean   :1.811   Mean   :1.303  
##  3rd Qu.:4.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:2.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item17          Item18          Item19          Item20     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:2.000   1st Qu.:1.000   1st Qu.:0.000  
##  Median :2.000   Median :3.000   Median :1.000   Median :1.000  
##  Mean   :2.018   Mean   :2.449   Mean   :1.427   Mean   :1.577  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:2.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item21          Item22          Item23          Item24     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:3.000   1st Qu.:1.000   1st Qu.:2.000  
##  Median :3.000   Median :4.000   Median :3.000   Median :3.000  
##  Mean   :2.499   Mean   :3.167   Mean   :2.393   Mean   :2.697  
##  3rd Qu.:4.000   3rd Qu.:4.000   3rd Qu.:4.000   3rd Qu.:4.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item25          Item26          Item27          Item28     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:1.000   1st Qu.:2.000   1st Qu.:1.000  
##  Median :2.000   Median :2.000   Median :3.000   Median :2.000  
##  Mean   :2.172   Mean   :2.018   Mean   :2.744   Mean   :2.099  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:4.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item29          Item30          Item31          Item32     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:0.000   1st Qu.:1.000   1st Qu.:0.000  
##  Median :2.000   Median :1.000   Median :2.000   Median :1.000  
##  Mean   :1.938   Mean   :1.597   Mean   :2.208   Mean   :1.576  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item33          Item34          Item35          Item36     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:2.000   1st Qu.:1.000   1st Qu.:2.000  
##  Median :1.000   Median :3.000   Median :2.000   Median :3.000  
##  Mean   :1.713   Mean   :2.503   Mean   :1.873   Mean   :2.505  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:4.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item37          Item38          Item39          Item40     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:2.000   1st Qu.:1.000   1st Qu.:1.000   1st Qu.:1.000  
##  Median :2.000   Median :2.000   Median :1.000   Median :2.000  
##  Mean   :2.451   Mean   :1.784   Mean   :1.939   Mean   :2.095  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item41          Item42          Item43          Item44     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:0.000   1st Qu.:0.000   1st Qu.:1.000  
##  Median :2.000   Median :1.000   Median :2.000   Median :3.000  
##  Mean   :2.047   Mean   :1.349   Mean   :1.603   Mean   :2.296  
##  3rd Qu.:3.000   3rd Qu.:2.000   3rd Qu.:3.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000  
##      Item45          Item46          Item47         Item48     
##  Min.   :0.000   Min.   :0.000   Min.   :0.00   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:1.000   1st Qu.:0.00   1st Qu.:1.000  
##  Median :3.000   Median :1.000   Median :1.00   Median :2.000  
##  Mean   :2.289   Mean   :1.723   Mean   :1.49   Mean   :2.112  
##  3rd Qu.:4.000   3rd Qu.:2.000   3rd Qu.:3.00   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.00   Max.   :4.000  
##      Item49          Item50          Item51          Item52    
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.00  
##  1st Qu.:1.000   1st Qu.:1.000   1st Qu.:1.000   1st Qu.:1.00  
##  Median :1.000   Median :2.000   Median :3.000   Median :3.00  
##  Mean   :1.988   Mean   :1.793   Mean   :2.459   Mean   :2.47  
##  3rd Qu.:4.000   3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:4.00  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.00  
##      Item53           Item54         Item55          Item56     
##  Min.   :0.0000   Min.   :0.00   Min.   :0.000   Min.   :0.000  
##  1st Qu.:0.0000   1st Qu.:0.00   1st Qu.:0.000   1st Qu.:1.000  
##  Median :1.0000   Median :1.00   Median :1.000   Median :2.000  
##  Mean   :0.9477   Mean   :1.01   Mean   :1.392   Mean   :2.007  
##  3rd Qu.:2.0000   3rd Qu.:2.00   3rd Qu.:2.000   3rd Qu.:4.000  
##  Max.   :4.0000   Max.   :4.00   Max.   :4.000   Max.   :4.000  
##      Item57          Item58          Item59          Item60     
##  Min.   :0.000   Min.   :0.000   Min.   :0.000   Min.   :0.000  
##  1st Qu.:1.000   1st Qu.:0.000   1st Qu.:2.000   1st Qu.:1.000  
##  Median :2.000   Median :1.000   Median :3.000   Median :2.000  
##  Mean   :1.925   Mean   :1.755   Mean   :2.519   Mean   :1.864  
##  3rd Qu.:3.000   3rd Qu.:3.000   3rd Qu.:4.000   3rd Qu.:3.000  
##  Max.   :4.000   Max.   :4.000   Max.   :4.000   Max.   :4.000

Partial Credit Models (PCM) with R Output

## 
## Call:
## mirt(data = Data_OAlwusaidi_GPCM, model = model.pcm, itemtype = "Rasch", 
##     SE = TRUE, verbose = FALSE)
## 
## Full-information item factor analysis with 1 factor(s).
## Converged within 1e-04 tolerance after 37 EM iterations.
## mirt version: 1.30 
## M-step optimizer: nlminb 
## EM acceleration: Ramsay 
## Number of rectangular quadrature: 61
## Latent density type: Gaussian 
## 
## Information matrix estimated with method: Oakes
## Condition number of information matrix = 1135.934
## Second-order test: model is a possible local maximum
## 
## Log-likelihood = -761541.2
## Estimated parameters: 241 
## AIC = 1523564; AICc = 1523576
## BIC = 1525302; SABIC = 1524536
## G2 (1e+10) = 1338876, p = 1
## RMSEA = 0, CFI = NaN, TLI = NaN

Partial Credit Models (GPCM) with R Output

## 
## Call:
## mirt(data = Data_OAlwusaidi_GPCM, model = model.gpcm, itemtype = "gpcm", 
##     SE = TRUE, verbose = FALSE)
## 
## Full-information item factor analysis with 1 factor(s).
## Converged within 1e-04 tolerance after 145 EM iterations.
## mirt version: 1.30 
## M-step optimizer: BFGS 
## EM acceleration: Ramsay 
## Number of rectangular quadrature: 61
## Latent density type: Gaussian 
## 
## Information matrix estimated with method: Oakes
## Condition number of information matrix = 8432.643
## Second-order test: model is a possible local maximum
## 
## Log-likelihood = -723068.2
## Estimated parameters: 300 
## AIC = 1446736; AICc = 1446755
## BIC = 1448899; SABIC = 1447946
## G2 (1e+10) = 1261930, p = 1
## RMSEA = 0, CFI = NaN, TLI = NaN

Visualizing Polytomous IRT Models PCM

## Visualizing Polytomous IRT Models GPCM