sgl_fit: Fit a Sparse Group Lasso Regularization Path.

Description Usage Arguments Value Author(s)

Description

Computes a sequence of minimizers (one for each lambda given in the lambda argument) of

\mathrm{loss}(β) + λ ≤ft( (1-α) ∑_{J=1}^m γ_J \|β^{(J)}\|_2 + α ∑_{i=1}^{n} ξ_i |β_i| \right)

where \mathrm{loss} is the loss/objective function specified by module_name. The parameters are organized in the parameter matrix β with dimension q\times p. The vector β^{(J)} denotes the J parameter group. The group weights γ \in [0,∞)^m and the parameter weights ξ = (ξ^{(1)},…, ξ^{(m)}) \in [0,∞)^n with ξ^{(1)}\in [0,∞)^{n_1},…, ξ^{(m)} \in [0,∞)^{n_m}.

Usage

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sgl_fit(module_name, PACKAGE, data, parameterGrouping = NULL,
  groupWeights = NULL, parameterWeights = NULL, alpha, lambda,
  d = 100, compute_lambda = length(lambda) == 1,
  return_indices = NULL, algorithm.config = sgl.standard.config)

Arguments

module_name

reference to objective specific C++ routines.

PACKAGE

name of the calling package.

data

a list of data objects – will be parsed to the specified module.

parameterGrouping

grouping of parameters, a vector of length p. Each element of the vector specifying the group of the parameters in the corresponding column of β.

groupWeights

the group weights, a vector of length length(unique(parameterGrouping)) (the number of groups).

parameterWeights

a matrix of size q \times p.

alpha

the α value 0 for group lasso, 1 for lasso, between 0 and 1 gives a sparse group lasso penalty.

lambda

lambda.min relative to lambda.max (if compute_lambda = TRUE) or the lambda sequence for the regularization path, a vector or a list of vectors (of the same length) with the lambda sequence for the subsamples.

d

length of lambda sequence (ignored if compute_lambda = FALSE)

compute_lambda

should the lambda sequence be computed

return_indices

the indices of lambda values for which to return fitted parameters.

algorithm.config

the algorithm configuration to be used.

Value

Y.true

the response, that is the y object in data as created by create.sgldata.

beta

the fitted parameters – a list of length length(return) with each entry a matrix of size q\times (p+1) holding the fitted parameters.

loss

the values of the loss function.

objective

the values of the objective function (i.e. loss + penalty).

lambda

the lambda values used.

Author(s)

Martin Vincent


sglOptim documentation built on May 8, 2019, 1:02 a.m.