Latent growth curve model with individually varying time points

[Isabelle Hansson]

Is it possible to estimate growth curves with individually varying time points (e.g., time to event instead of time in study) in lavaan? And if so, how would I go about to specify this model? 

Thanks in advance!

Best regards,

Isabelle Hansson

Department of Psychology

University of Gothenburg

Gothenburg, Sweden

[Terrence Jorgensen]

Is it possible to estimate growth curves with individually varying time points (e.g., time to event instead of time in study) in lavaan? 

No.  I don't think there is a straight-forward way to incorporate this idea into parameter table that lavaan uses to represent its models (?lavaanify output).  If you are comfortable editing a JAGS or Stan syntax file, you could specify the basic growth model (with loadings fixed according to the number of waves) using the blavaan package, and save the JAGS or Stan syntax file. Then you can edit that to replace the constant loadings with person-specific specific loadings stored as additional variables in your data.

Terrence D. Jorgensen

Postdoctoral Researcher, Methods and Statistics

Research Institute for Child Development and Education, the University of Amsterdam

http://www.uva.nl/profile/t.d.jorgensen

[Isabelle Hansson]

Dear Dr. Jorgensen,

Thank you for your quick and helpful response. I will look into this in more detail. 

Best regards,

Isabelle 

[Jack Bailey]

Hi Isabelle,

You can do this is OpenMX using definition variables. There's a good example in this book.

[Isabelle Hansson]

Thanks for the advice Jack!