test for single predictor chi2 vs multigroup

tests/testthat/test-single-predictor.R

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+library(lavaan)
+library(semtree)
+set.seed(1238)
+
+N <- 500
+
+# simulate data with Cohen's d = 2
+da <- data.frame(y = c(rnorm(N/2, mean = -1), rnorm(N/2, mean = 1)),
+                   z = rep(c(0,1),each=N/2) )
+
+m_lav <- '
+y ~~ y
+y ~ 1
+'
+
+m_lav_constrained <- '
+y ~~ y
+y ~ c(a,a)*1
+'
+
+####Testing semtree with lavaan models ####
+fit_lav <- lavaan(model = m_lav, data = Data)
+
+forest <- semforest(model=fit_lav, data=da, 
+          control = semforest.control(
+            num.trees = 50, control=semtree_control(method="score")))
+
+vim <- varimp(forest)
+
+plot(vim)
+
+zimp <- semtree:::aggregateVarimp(vim)
+
+fit_lav_multigroup <- lavaan(model = m_lav, data = da,group = "z")
+fit_lav_multigroup2 <- lavaan(model = m_lav_constrained, data = da,group = "z")
+lrt <- anova(fit_lav_multigroup,fit_lav_multigroup2)
+chi2 <- lrt$`Chisq diff`[2]
+
+
+cat("Importance: ", zimp,"\n")
+cat("MG Chi^2: ",chi2,"\n")