itemfit.ppar {eRm} | R Documentation |
pmat
computes the theoretical person-item matrix with solving
probabilities for each category (except 0th). residuals
computes the squared and standardized residuals based on
the observed and the expected person-item matrix. Chi-square based itemfit and personfit
statistics can be obtained by using itemfit
and personfit
.
## S3 method for class 'ppar' pmat(object) ## S3 method for class 'ppar' residuals(object,...) ## S3 method for class 'ppar' itemfit(object) ## S3 method for class 'ppar' personfit(object) ## S3 method for class 'ifit' print(x, visible = TRUE, ...) ## S3 method for class 'pfit' print(x, visible = TRUE, ...) ## S3 method for class 'resid' print(x, ...)
object |
Object of class |
x |
Object of class |
visible |
if |
... |
Further arguments passed to or from other methods. They are ignored in this function. |
pmat |
Matrix of theoretical probabilities for each category except 0th (from function |
i.fit |
Chi-squared itemfit statistics (from function |
i.df |
Degrees of freedom for itemfit statistics (from function |
st.res |
Standardized residuals (from function |
i.outfitMSQ |
Outfit mean-square statistics (from function |
i.infitMSQ |
Infit mean-square statistics (from function |
p.fit |
Chi-squared personfit statistics (from function |
p.df |
Degrees of freedom for personfit statistics (from function |
st.res |
Standardized residuals (from function |
p.outfitMSQ |
Outfit mean-square statistics (from function |
p.infitMSQ |
Infit mean-square statistics (from function |
Patrick Mair, Reinhold Hatzinger
Smith Jr., E. V., and Smith, R. M. (2004). Introduction to Rasch Measurement. JAM press.
Wright, B.D., and Masters, G.N. Computation of OUTFIT and INFIT Statistics. Rasch Measurement Transactions, 1990, 3:4 p.84-5
# Rasch model, estimation of item and person parameters res <- RM(raschdat2) p.res <- person.parameter(res) # Matrix with expected probabilities and corresponding residuals pmat(p.res) residuals(p.res) #Itemfit itemfit(p.res) #Personfit personfit(p.res)