Update the Model
The current model of the WAIS-III indicated a Heywood case between perceptual organization and processing speed. To fix a highly correlated set of latent variables, you should collapse those two variables into one latent variable. You should make a performance variable that combines the manifest variables for the perceptorg and processing latent variables.
The data has been loaded for you and is called IQdata. You can view the data using head(IQdata).
Questo esercizio fa parte del corso
Structural Equation Modeling with lavaan in R
Istruzioni dell'esercizio
- Edit the four-factor model to include one
performancevariable measured bypiccomp,block,matrixreason,digsym, andsymbolsearch. - Use the
cfa()function to analyze the model for any new errors. - Summarize the model to determine model fit with the standardized solution and fit indices.
Esercizio pratico interattivo
Prova a risolvere questo esercizio completando il codice di esempio.
# Edit the original model
wais.model <- 'verbalcomp =~ vocab + simil + inform + compreh
workingmemory =~ arith + digspan + lnseq
perceptorg =~ piccomp + block + matrixreason
processing =~ digsym + symbolsearch'
# Analyze the model and include the model and data argument
wais.fit <- cfa(___)
# Summarize the model
summary(___)