ECV_SS {BifactorIndicesCalculator} | R Documentation |
Computes an ECV index for all factors which can be interpreted as the proportion of common
variance of the items in each factor which is due to that factor;
ECV_SS
should be read 'ECV of a specific factor with respect to itself.' Here, ECV is computed
only with respect to items which load on the factor. Note that ECV_SS
of the general factor
is simply the ECV. Stucky and Edelen (2015, p. 201) do not refer to this form of ECV. In the Excel
version of the bifactor indices calculator (Dueber, 2017), this index is referred to as
'ECV (NEW).' ECV_SS
is useful in that it can be computed when there is no general factor, such
as in a two-tier model, and interpreted in the same way as ECV for general factors.
ECV_SS(Lambda)
Lambda |
is a matrix of factor loadings. Be sure that all factors have the same variance before calling this function. |
ECV_SS
is called by bifactorIndices
and the various convenience functions
for exploratory models and/or Mplus output,
which are the only functions in this package intended for casual users.“
A vector of ECVs for all factors
Dueber, D. M. (2017). Bifactor Indices Calculator: A Microsoft Excel-based tool to calculate various indices relevant to bifactor CFA models. doi: 10.13023/edp.tool.01
Stucky, B. D., & Edelen, M. O. (2015). Using hierarchical IRT models to create unidimensional measures from multidimensional data. In S. P. Reise & D. A. Revicki (Eds.), Handbook of item response theory modeling: Applications to typical performance assessment (pp.183-206). New York: Routledge.
ECV_SG
, ECV_GS
, bifactorIndices
Lambda <- matrix(c(.82, .10, 0, 0, .77, .35, 0, 0, .79, .32, 0, 0, .66, .39, 0, 0, .51, 0, .71, 0, .56, 0, .43, 0, .68, 0, .13, 0, .60, 0, .50, 0, .83, 0, 0, .47, .60, 0, 0, .27, .78, 0, 0, .28, .55, 0, 0, .75), ncol = 4, byrow = TRUE) colnames(Lambda) <- c("General", "SF1", "SF2", "SF3") ECV_SS(Lambda)