Define lower-upper bound for parameters in Optim using Nelder-Mead method
Ben Bolker <bbolker <at> gmail.com> writes:
<Ted.Harding <at> wlandres.net> writes: In addition to these options, there is also a derivative-free box-constrained optimizer (bobyqa) in the 'minqa' package (and in an optim-like wrapper via the optimx package), and a box-constrained Nelder-Mead optimizer in the development (r-forge) version of lme4, which is based on the NLopt optimization library (also accessible via the nloptr package).
I could add another Nelder-Mead implementation in package 'dfoptim'. It comes in pure R and is still quite efficient, based on Kelley's well-known book code. It exists in unconstrained and box-constraint versions. The "optimization world" in R is by now really scattered across many different package with sometimes 'strange' names. Some of the packages have not yet made it from R-Forge to CRAN. Unfortunately, the Optimization task view is not of much help anymore in this shattered world. We will get a lot more of these questions on R-help if we do not come up with a solution to this problem, for instance more up-to-date optimization functions in R base, a recommened package for optimization, or e.g. an optimization guide as a kind of global vignette. Hans Werner