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John Baez (Jun 07 2025 at 14:37):You may have heard of CatColab, a software platform based on double categories, pioneered by @Evan Patterson, @Kevin Carlson and perhaps others at the Topos Institute. You can read about some basics here.
You may also have heard of causal loop diagrams, which are graphs with edges labeled by signs (or other information), used as simple models in the field of System Dynamics.
Catcolab can handle causal loop diagrams, and @Nathaniel Osgood has just announced a bunch of examples created by students at the Computational Epidemiology and Public Health Informatics Lab, notably @Mehdi Tafaroji.
Check them out!
Impact of Physician Trust on Physician and Patient Dynamics.
Service Dogs and Veterans Struggling with PTSD, Mental Health and Substance Use Challenges.
To see these rendered visually, click on the menu on the upper left and click on the "New analysis of this model" menu item. A panel will appear on the right, and near the top left of that panel you should see a title "Analysis". Just under that title, there should be "Select cell type" label (probably in gray). If you place your mouse over that, a "+" should appear to its left. When you click on that "+" mark, you should get a menu. Click on "Visualization".