initial value for \(\beta\); default - zero vector of size \(n \times 1\)
lambda1
lasso penalty coefficient
lambda2
network penalty coefficient
M1
penalty matrix
n.iter
maximum number of iterations for \(\beta\) updating; default - 1e5
iscpp
binary choice for using cpp function in coordinate updates; 1 - use C++ (default), 0 - use R.
tol
convergence in \(\beta\) tolerance level; default - 1e-6
Value
beta
Matrix of \(\beta\) coefficients. Columns denote different \(\lambda\)1
coefficients, rows - \(\lambda\)2 coefficients
mse
Mean squared error value
iterations
matrix with stored number of steps for sign matrix to converge
update.steps
matrix with stored number of steps for \(\beta\) updates to converge. (only stores the last values from connection signs iterations)
convergence.in.grid
matrix with stored values for convergence in \(\beta\) coefficients. If at least one \(\beta\) did not converge in sign matrix iterations, 0 (false) is stored, otherwise 1 (true)
Details
Function loops through the grid of values of penalty parameters \(\lambda\)1 and \(\lambda\)2 until convergence is reached. Warm starts are stored for each iterator. The warm starts are stored once the coordinate updating converges.
References
Weber, M., Striaukas, J., Schumacher, M., Binder, H. "Network-Constrained Covariate Coefficient and Connection Sign Estimation" (2018) <doi:10.2139/ssrn.3211163>