Abstract: Quasi-Regression is introduced for approximation of a function in high dimensional space in recent literature.It was very highly computationally efficient.But the accuracy of approximation to an unknown function depends on estimators of scalar coefficients.In this paper,the authors provide new estimators of scalar coefficients,and obtain more accurate fitted function of an unknown function than the usual ones.

Key words: Quasi-Regression, computer experiments, orthogonal basis function, least square estimate