lordif (version 0.1-1)

tcc: computes a test characteristic curve (tcc)

Description

computes a test characteristic curve (tcc) from input item parameters

Usage

tcc(a, cb, theta)

Arguments

a

a vector of slope parameters

cb

a matrix of category boundary/threshold parameters

theta

a grid of theta values

Value

• Retruns a vector representing a tcc

Details

The graded response model is assumed. The lowest score for each item is set to 0 not 1. length(a) must be the same as nrow(cb)

References

Samejima, F. (1969). Estimation of latent ability using a response pattern of graded scores. Psychometrika Monograph, 17.

See Also

equate, probgrm

Examples

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tcc(a,cb,theta)