CRAN release 0.5.0

New features

New additive explainer additive_shap() that works for models fitted via

• lm(),
• glm(),
• mgcv::gam(),
• mgcv::bam(),
• gam::gam(),
• survival::coxph(),
• survival::survreg().

The explainer uses predict(..., type = "terms"), a beautiful trick
used in fastshap::explain.lm(). The result will be identical to those returned by kernelshap() and permshap() but exponentially faster. Thanks David Watson for the great idea discussed in #130.

User visible changes

• permshap() now returns an object of class "kernelshap" to reduce the number of redundant methods.
• To distinguish which algorithm has generated the "kernelshap" object, the outputs of kernelshap(), permshap() (and additive_shap()) got an element "algorithm".
• is.permshap() has been removed.