expandX: Expand design matrix according to grouping information
In grpregOverlap: Penalized Regression Models with Overlapping Grouped Covariates

Description Usage Arguments Value Note Author(s) See Also Examples

expandX creates a new design matrix by duplicating the columns of the overlapped variables in design matrix X.

1	expandX(X, group)

`X`	The design matrix, without an intercept, as in `grpregOverlap`.
`group`	A list of vectors containing group information, as in `grpregOverlap`.

A matrix expanded based on X, with duplicated columns corresponding to variables being overlapped between groups.

When expanding X, The columns of X corresponding to the variables not included in group will be removed automatically.

Yaohui Zeng <yaohui-zeng@uiowa.edu>

grpregOverlap, overlapMatrix.

set.seed(123)
group <- list(gr1 = c(1, 2, 3), gr2 = c(1, 4), gr3 = c(2, 4, 5), 
              gr4 = c(3, 5), gr5 = c(6))
beta.latent.T <- c(5, 5, 5, 0, 0, 0, 0, 0, 5, 5, 0) # true latent coefficients.
# beta.T <- c(2, 3, 7, 0, 5, 0), true variables: 1, 2, 3, 5; true groups: 1, 4.
X <- matrix(rnorm(n = 6*100), ncol = 6)  
X.latent <- expandX(X, group)