Andrew and I have both written here about our Software Validation paper with Don Rubin. The last thing to add on the topic is that my website now has newly updated software to implement our validation method (go down to Research Software and there are .zip and .tar versions of the R package). If the software you want to validate isn’t written in R, you can always write an R function that calls the other program. Feel free to contact me (email@example.com) with questions, comments, etc.
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