#probula — Public Fediverse posts

// nerd-mode

A small step for the humankind, a huge celebration for my inner nerd.  The most beautiful formulation of Fisher's 1922 dilution assay model in the history of humankind has landed 😊.

A lot has been happening in Probula lately, but chiefly I worked on syntax to allow expressing more complex models, and doing this concisely and elegantly.  The picture shows Fisher's (1922) dilution assay model.  The first non-trivially-structured model that I implemented in Probula; also one whose structure is parametric (depends on the number of dilution stages).

The screenshot shows the entire model, including the inference call. Each line corresponds directly to the piece of math it implements, so the model is almost identical to what McCullagh and Nelder (1989) describe. I think this is amazing. And of course samples very well :) The posterior sd matches Fisher's asymptotic formula to a fraction of a percent.

I will be writing more about this online soon, and wrapping up a Probula release, before my students hit the topic this term.

#scala #scala3 #ScalaLang #probula #ppl #ProbabilisticProgramming #Fisher1922 #statistics #glm #keep

Links: To find this model on codeberg search for FisherIntegrated here https://codeberg.org/wasowski/probula/src/branch/main/doc/example/Fisher1922.scala

//nerd-out