sem program

# Load package lavaan
vs = as.numeric(R.version$major)+as.numeric(R.version$minor)
if(vs < 3.5){
  cat(paste("Minimun version is 3.5. Your R version is", vs,"\n"))
  quit()
}

for(p in c('lavaan')){
  if(!require(p,character.only = TRUE)) install.packages(p)
  library(p,character.only = TRUE)
}

# Load data sample.csv
myData = read.csv('sample.csv')
myData

# membangun model
myModel <- '
  # measurement model
    ind60 =~ x1 + x2 + x3
    dem60 =~ y1 + y2 + y3 + y4
    dem65 =~ y5 + y6 + y7 + y8
  # regressions
    dem60 ~ ind60
    dem65 ~ ind60 + dem60
  # residual correlations
    y1 ~~ y5
    y2 ~~ y4 + y6
    y3 ~~ y7
    y4 ~~ y8
    y6 ~~ y8
'
# Analsiis
fit <- sem(model = myModel, data = myData)
summary(fit, fit.measures = TRUE)