Desktop Survival Guide
by Graham Williams

Tuning parameters

Rarg[]rang= is the range for the initial random weights from -rang to rang. The values should be about 0.5 unless the inputs are large, in which case it should be chosen so that the value of rang * max(|x|) is about 1. Todo: Perhaps Rattle can determine a reasonable default value based on the data.

Rarg[]decay= is used to change from the default decay parameter of 0. Todo: How to choose a decay value.

Rarg[]skip= will toggle the use of a so called ``skip-layer'' where the input variables are connected directly to the output variable. They are enabled by default, so the author of the package must think they are useful. The skip-layer essentially results in the model being a perturbation of a linear hyperplane where we can think of the direct links (i.e., the skip-layer) representing a plane, and the rest of the model then representing a perturbation to the plane.()

The ada package for boosting was implemented by Mark Culp, Kjell Johnson, and George Michailidis, and is described in ().

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