lavaan - latent variable analysis

Welcome to the lavaan.org website. This site will provide documentation and user support for the lavaan package.

What is lavaan?

lavaan is a free, open source R package for latent variable analysis. You can use lavaan to estimate a large variety of multivariate statistical models, including path analysis, confirmatory factor analysis, structural equation modeling and growth curve models.

The lavaan package is developed to provide useRs, researchers and teachers a free open-source, but commercial-quality package for latent variable modeling. The long-term goal of lavaan is to implement all the state-of-the-art capabilities that are currently available in commercial packages. However, lavaan is still under development, and much work still needs to be done. For an overview of the current features of lavaan, click on the 'Features' item in the menu.

To get a first impression of how lavaan works in practice, consider the following example of a SEM model. The left panel of the figure below contains a graphical representation of the model that we want to fit. The right panel contains the corresponding R code using the lavaan package:

library(lavaan) model <- '    # latent variables      ind60 =~ x1 + x2 + x3      dem60 =~ y1 + y2 + y3 + y4      dem65 =~ y5 + y6 + y7 + y8    # regressions      dem60 ~ ind60      dem65 ~ ind60 + dem60    # residual covariances      y1 ~~ y5      y2 ~~ y4 + y6      y3 ~~ y7      y4 ~~ y8      y6 ~~ y8 ' fit <- sem(model, data=PoliticalDemocracy) summary(fit)

Many more examples can be found in the documentation.

Disclaimer: the lavaan package is still under development. You can use it, but things may change in the future. If you find any bugs, or if you have any suggestions, we would be happy to hear from you.