utils: Utility functions In Rirt: Data Analysis and Parameter Estimation Using Item Response Theory

Description

rmse computes the root mean squared error (RMSE) of two numeric vectors/matrices

freq computes the frequency counts of a numeric or character vector

cronbach_alpha computes the Cronbach's alpha internal consistency reliability index

spearman_brown predicts the reliability when the current test is extended to n times longer

spearman_brown_reverse computes how many times the current test length needs to be extended in order to reach targeted reliability

Usage

 1 2 3 4 5 6 7 8 9 10 11 rmse(x1, x2) freq(x, vals = NULL, decimal = NULL) cronbach_alpha(u) spearman_brown(rho, n_len) spearman_brown_reverse(rho, target_rho) quadratic_kappa(x1, x2)

Arguments

 x1 a numeric vector or matrix x2 a numeric vector or matrix x a numeric or character vector vals valid values, NULL to include all values decimal round results to n-th decimal places u oberved responses, 2d matrix rho the reliability of the current test n_len extend the test to n times longer target_rho the targeted reliability

Value

freq returns the frequency counts and percentages in a data.frame

Examples

 1 2 3 4 5 6 rmse(rnorm(10), rnorm(10)) freq(round(runif(100, 1, 5))) cronbach_alpha(model_3pl_gendata(1000, 20)\$u) spearman_brown(.70, 2) spearman_brown_reverse(.70, .85) quadratic_kappa(round(runif(100, 1, 5)), round(runif(100, 1, 5)))

Rirt documentation built on Oct. 30, 2019, 12:13 p.m.