measEq.syntax-class: Class for Representing a Measurement-Equivalence Model

measEq.syntax-classR Documentation

Class for Representing a Measurement-Equivalence Model


This class of object stores information used to automatically generate lavaan model syntax to represent user-specified levels of measurement equivalence/invariance across groups and/or repeated measures. See measEq.syntax for details.


## S4 method for signature 'measEq.syntax'
as.character(x, package = "lavaan",
  params = NULL, single = TRUE, = FALSE)

## S4 method for signature 'measEq.syntax'

## S4 method for signature 'measEq.syntax'
summary(object, verbose = TRUE)

## S4 method for signature 'measEq.syntax'
update(object, ..., evaluate = TRUE, change.syntax = NULL)


x, object

an object of class measEq.syntax


character indicating the package for which the model syntax should be generated. Currently, only "lavaan" and "mplus" are supported.


character vector indicating which type(s) of parameter to print syntax for. Must match a type that can be passed to group.equal or long.equal, but "residual.covariances" and "lv.covariances" will be silently ignored. Instead, requesting "residuals" or "lv.variances" will return covariances along with variances. By default (NULL), all types are printed.


logical indicating whether to concatenate lavaan model.syntax into a single character string. Setting FALSE will return a vector of strings, which may be convenient (or even necessary to prevent an error) in models with long variable names, many variables, or many groups.

logical indicating whether to write lavaan model.syntax using vectors of labels and values for multiple groups (the default: FALSE), or whether to write a separate "block" of syntax per group. The block structure could allow users to apply the generated multigroup syntax (after some editing) to test invariance across levels in a multilevel SEM (see final example on measEq.syntax help page).


logical indicating whether to print a summary to the screen (default). If FALSE, only a pattern matrix is returned.


Additional arguments to the call, or arguments with changed values.


If TRUE, evaluate the new call; otherwise, return the new call.


lavaan model.syntax specifying labels or fixed/free values of parameters in object. These provide some flexibility to customize existing parameters without having to copy/paste the output of as.character(object) into an R script. For example, group.partial will free a parameter across all groups, but update allows users to free the parameter in just one group while maintaining equality constraints among other groups.



signature(object = "measEq.syntax", verbose = TRUE): A character matrix indicating the pattern of numeric, ordered, or latent indicators loading on common factors. By default (verbose = TRUE), summary also prints descriptive details about the model, including the numbers of indicators and factors, and which parameters are constrained to equality.


signature(object = "measEq.syntax"): Prints a message about how to use the object for model fitting. Invisibly returns the object.


signature(object = "measEq.syntax", ..., evaluate = TRUE, change.syntax = NULL): Creates a new object with updated arguments in ..., or updated parameter labels or fixed/free specifications in object.


signature(x = "measEq.syntax", package = "lavaan"): Converts the measEq.syntax object to model syntax that can be copy/pasted or written to a syntax file to be edited before analysis, or simply passed to lavaan to fit the model to data. Generated Mplus syntax could also be utilized using the MplusAuthomation package.



character indicating the software package used to represent the model. Currently, only "lavaan" is available, which uses the LISREL representation (see lavOptions). In the future, "OpenMx" may become available, using RAM representation.


character. Currently, only "cfa" is available. Future versions may allow for MIMIC / RFA models, where invariance can be tested across levels of exogenous variables explicitly included as predictors of indicators, controlling for their effects on (or correlation with) the common factors.


The function call as returned by, with some arguments updated if necessary for logical consistency.


logical indicating whether a mean structure is included in the model.


character vector naming numeric manifest indicators.


character vector naming ordered indicators.


character. See lavOptions.


list of parameter matrices, similar in form to the output of lavInspect(fit, "free"). These matrices are logical, indicating whether each parameter should be specified in the model syntax.


list of parameter matrices, similar in form to the output of lavInspect(fit, "free"). These matrices are numeric, indicating whether each parameter should be freely estimated (indicated by NA) or fixed to a particular value.


list of parameter matrices, similar in form to the output of lavInspect(fit, "free"). These matrices contain character labels used to constrain parameters to equality.


character vector containing additional equality constraints used to identify the model when ID.fac = "fx".


integer indicating the number of groups.


Terrence D. Jorgensen (University of Amsterdam;


## See ?measEq.syntax help page for examples using lavaan

semTools documentation built on May 10, 2022, 9:05 a.m.