We consider a joint processing of n independent sparse regression problems. Each is based on a sample (yi1, xi1) . . . , (yim, xim) of m i.i.d. observations from yi1 = x T i1βi+εi1, yi1 ∈ R, xi1 ∈ R, i = 1, . . . , n, and εi1 ∼ N(0, σ), say. p is large enough so that the empirical risk minimizer is not consistent. We consider three possible extensions of the lasso estimator to deal with this pr...