Good Ways to Visualize Longitudinal Categorical Data in R

Question

[Update: Although I\'ve accepted an answer, please add another answer if you have additional visualization ideas (whether in R or another language/program). Tex

Answer 1

In researching my question, I've found a few other options that I'll list here.

A number of relatively new R packages are designed for visualizing and analyzing "life history" or "multistate sequence" data. The idea is that over time people (or objects) enter and exit various categories--for example, career changes, marriage and divorce, health and disease, or, in my case, categories of academic standing in college.

R packages for visualizing sequence or life history data include biograph, mentioned by @timriffe in a comment above, and TraMineR. The author of the biograph package, Frans Willekens, has a book on the package, Biograph. Multistate analysis of life histories with R, that will be published by Springer this fall. TraMineR has a detailed user manual at the link above and also a shorter JSS article. JSS also has a special issue on multi-state models in the context of risk analysis that discusses additional R packages for multistate modeling.

I also found some specialized software designed to visualize movements between categories over time. Parallel Sets is a simple, free program for producing basic visualizations, although it has limited flexibility. Lifeflow is more sophisticated. It's also free, but you have to send an email to the creator requesting a copy.

I'll add more details to this answer, once I've had a chance to try out these tools.