Cronbachs-alpha: Alpha de Cronbach

Description Usage Arguments Details Value References

Description

Cronbach's alpha measures how correlated are the items in a test License :GPL (>= 2) Extracted from multilevel_2.5 package

Usage

1
cronbach(test)

Arguments

test

a matrix or a Dataframe that holds the test response data

Details

the coefficient is calculated alpha = (n/n-1)*(1 - (sum V_i/V_t)) where V_t is the variance of test scores and V_i is the variance of item scores. It is desirable that the items are closely interrelated (coefficient near 1).

Value

Cronbach's alpha for the test.

References

Cronbach L. J. (1951) Coefficient Alpha and the internal structure of tests. Psychometrika, 16,297-334


SICSresearch/IRTpp_old documentation built on May 9, 2019, 11:12 a.m.