  We propose a simple scheme to estimate potential energy surface (PES) with
which the accuracy can be easily controlled and improved up to the level of the
density functional theory (DFT) calculations. It is based on a model selection
within the framework of linear regression using the least absolute shrinkage
and selection operator (LASSO) technique. Basis functions are selected from a
systematic large set of candidate functions. The sparsity of PES significantly
reduces the computational demands for evaluation of the energy and the force in
molecular dynamics simulations without losing the accuracy. The usefulness of
the scheme is well demonstrated for describing elemental metals of Na and Mg.
