Improvement of grey models by least squares

In this paper, we present an approach to the least squares solution to grey Verhulst model, and verify its feasibility by numerical examples. We also present the least squares solutions of grey models GM (1, 1) and GM (2, 1). For the convenience of applications in expert systems, the parameters computing formulas of grey models are also presented here. We carry out some numerical examples to examine the modeling precision of grey models in conventional way and in least squares. The numerical results reveal that the modeling precision of grey models in least squares is always better than that in conventional way.