On the identification of zero variables in an interior-point framework

We consider column sufficient linear complementarity problems and study the problem of identifying those variables that are zero at a solution. To thi s end we propose a new, computationally inexpensive technique that is based on growth functions. We analyze in detail the theoretical properties of th e identification technique and test it numerically. The identification tech nique is particularly suited to interior-point methods but can be applied t o a wider class of methods.