conogive v1.0.0


Monthly downloads



Congeneric Normal-Ogive Model

The congeneric normal-ogive model is a popular model for psychometric data (McDonald, R. P. (1997) <doi:10.1007/978-1-4757-2691-6_15>). This model estimates the model, calculates theoretical and concrete reliability coefficients, and predicts the latent variable of the model. This is the companion package to Moss (2020) <doi:10.31234/>.



Status AppVeyor Build

Codecov test
coverage DOI Project Status: Active – The project has reached a stable, usable
state and is being actively

An R package for the congeneric normal-ogive model.


The congeneric normal-ogive model (McDonald, R. P., 1997) is a psychometric model for Likert data with one latent factor. This package has functions to estimate such models, calculate their ordinal reliabilities, and make predictions. It implements the concrete ordinal reliabilities of (Moss, 2020).


From inside R, use one of the following commands:



Estimate a congeneric normal-ogive model with congive, predict the value of the latent factor with predict, and calculate the reliability with ordinal_r.

extraversion = psychTools::bfi[c("E1", "E2", "E3", "E4", "E5")]
extraversion[, "E1"] = 7 - extraversion[, "E1"] # Reverse-coded item.
extraversion[, "E2"] = 7 - extraversion[, "E2"] # Reverse-coded item.

object = conogive(extraversion)

ordinal_r(object) # Observed reliability
#> [1] 0.7046056
theoretical_ordinal_r(object) # Theoretical reliability
#> [1] 0.8122607

hist(predict(object, extraversion)) # Plot distribution of predictions.


McDonald, R. P. (1997). Normal-ogive multidimensional model. In W. J. van der Linden & R. K. Hambleton (Eds.), Handbook of Modern Item Response Theory (pp. 257–269). Springer.

Moss, J. (2020). Please avoid the standardized alpha and the ordinal alpha.

Functions in conogive

Name Description
massage_cuts Massage Cuts to the Desired Shape
xi_theoretical Calculate the Theoretical Xi
xi_sample Calculate Sample Xi
conogive Estimate a Congeneric Normal-Ogive Model
ordered_y Transform y Into a Form Where Each Category is An Positive Integer
tr Trace of matrix
thurstone Thurstone weights
predict.conogive Predict Method for Conogive Objects
trim_vector Remove Infinities from Vector, Append and Prepend -Inf and Inf, and Sort
reliability Calculate the Ordinal Reliabiltiy
x_hat Transform Likert data to X_hats.
standardize Standardize Parameter Vectors
No Results!

Last month downloads


License MIT + file LICENSE
Encoding UTF-8
LazyData true
RoxygenNote 7.1.0
NeedsCompilation no
Packaged 2020-06-30 10:02:28 UTC; jonas
Repository CRAN
Date/Publication 2020-06-30 10:30:02 UTC

Include our badge in your README