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adolgert / Glissa.jl

Spline functions for unequal coordinates in pure Julia
MIT License
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shape constraints on P-splines #10

Open slwu89 opened 1 year ago

slwu89 commented 1 year ago

Wood and Pya (https://link.springer.com/article/10.1007/s11222-013-9448-7) present a method to set up constraints on P-splines (monotonic, convex/concave, etc). These kinds of constraints, along with max/min constraints would be very helpful for using these to fill in unknown functions in mechanistic models! For example, mosquito feeding rate should increase with increasing host density, but cannot exceed some maximum rate given by digestion/handling time.

slwu89 commented 1 year ago

Ch 8 of this book https://psplines.bitbucket.io/ claims that the Pya and Wood code implementation is wrong and that https://cran.r-project.org/web/packages/cgam/index.html is correct. I haven't looked at these claims or the "cgam" package in detail yet.

slwu89 commented 1 year ago

Interesting functions that seem relevant: https://www.stat.colostate.edu/~meyer/code.htm