IRTpp (version 0.2.6.1)

z3_personf: Z3 Person fit statistic

Description

Calculates the values of statistical Z3 for individuals.

Usage

z3_personf(data, zita, patterns)

Arguments

data

a data frame or a matrix with the test.

zita

a list of estimations of the parameters of the items (discrimination,difficulty, guessing).

patterns

matrix of patterns response, the frequency of each pattern and the latent traits.

References

Fritz Drasgow, Michael V. Levine and Esther A. Williams (1985). Appropiateness measurement with polychotomous item response models and standarized indices.

See Also

z3_itemf, orlando_itemf

Examples

#Simulates a test and returns a list:
test <- simulateTest()

#the simulated data:
data <- test$test

#model:
mod <- irtpp(dataset = data,model = "3PL")

#latent trait:
zz <- parameter.matrix(mod$z)
p_mat <- mod$prob_mat
traits <- individual.traits(model="3PL",method = "EAP",dataset = data,itempars = zz,
probability_matrix=p_mat)

#Z3 PERSONFIT-Statistic
z3_personf(data = data,zita = mod$z,patterns = traits)