Forum: DirichletReg 0.40 on RForge
Posted by: Marco J. Maier  the data structure of objects generated by DR_data() has been changed. it is no longer a list, but now a numeric matrix of class "DirichletRegData" with lots of attributes. this permits you to store the processed data in the original data.frame to keep your workspace tidy, e.g., > ArcticLake$Y < DR_data(ArcticLake[, 1:3]) so you can fit a model like: > DirichReg(Y ~ depth, ArcticLake) note that `free floating' dependent variables (i.e., not part of the data.frame) can also be used, as in prior versions.  formula processing is now handled by the package `Formula' which is much more robust than my `homemade' routines in earlier versions and has the advantage that  there is an update() method for Dirichlet regression models. so if you fit a model like > res1 < DirichReg(Y ~ depth + I(depth^2), ArcticLake) you can easily omit, e.g., the quadratic term for `sand' by typing > res2 < update(res1, . ~ . I(depth^2)) instead of having to specify a completely new model like > DirichReg(Y ~ depth  depth + I(depth^2)  depth + I(depth^2), ArcticLake) therefore, model selection is made a lot easier.  i did my best to complete the documentation which was a little fragmentary for some topics.  optimization settings have been tweaked and estimation is now both, faster, and more robust.  the package is now, by default, bytecompiled and therefore even faster.  some new methods for the class "DirichletRegModel" have been implemented.  DirichReg() has a couple of useful new features (subset, weights, etc.).  lots more ... please consult the documentation and have a look at the examples.

Latest NewsDirichletReg 0.61 on RForge and CRANMarco J. Maier  20141212 11:25 
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