lavTestWald: Wald test

View source: R/lav_test_Wald.R

lavTestWaldR Documentation

Wald test


Wald test for testing a linear hypothesis about the parameters of fitted lavaan object.


lavTestWald(object, constraints = NULL, verbose = FALSE)



An object of class lavaan.


A character string (typically between single quotes) containing one or more equality constraints. See examples for more details.


Logical. If TRUE, print out the restriction matrix and the estimated restricted values.


The constraints are specified using the "==" operator. Both the left-hand side and the right-hand side of the equality can contain a linear combination of model parameters, or a constant (like zero). The model parameters must be specified by their user-specified labels. Names of defined parameters (using the ":=" operator) can be included too.


A list containing three elements: the Wald test statistic (stat), the degrees of freedom (df), and a p-value under the chi-square distribution (p.value).


HS.model <- '
    visual  =~ x1 + b1*x2 + x3
    textual =~ x4 + b2*x5 + x6
    speed   =~ x7 + b3*x8 + x9

fit <- cfa(HS.model, data=HolzingerSwineford1939)

# test 1: test about a single parameter
# this is the 'chi-square' version of the 
# z-test from the summary() output
lavTestWald(fit, constraints = "b1 == 0")

# test 2: several constraints
con = '
   2*b1 == b3
   b2 - b3 == 0
lavTestWald(fit, constraints = con)

lavaan documentation built on July 26, 2023, 5:08 p.m.