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.

As part of an NWO-funded project for Dutch open-science infrastructural development, we are looking for a post-doc/programmer for the lavaan project. The position is initially for 1 year, but conditional on positive first-year review, it is designed to be extended to as many as 4 years. The job ad can be found on the University of Amsterdam (UVA) website, but it is also published on AcademicTransfer.com. And the same keywords can be searched to find the job posting on LinkedIn. The deadline is already 17 May 2026, but the deadline might be extended if sufficient candidates are not already found. The proposal for the full project can be found on Zenodo. The post-doc position above is part of Work Package 1 (WP1).

Install the stable version from CRAN:

install.packages("lavaan")

Or the development version from GitHub:

# install.packages("remotes")
remotes::install_github("yrosseel/lavaan")

To get a first impression of how lavaan works in practice, consider the following example of a SEM model (the Political Democracy Example from Bollen's 1989 book):

library(lavaan)

model <- '
   # latent variable definitions
     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)

More information can be found on the website: https://lavaan.org