Methods of line-fitting based on total least-squares

Abstract

Line fitting obtained by ordingary least square is often different if the independent variable is defferent,the reason that result in the defference is analysised in the paper. Then the method of line fitting by total least squares is proposed. We describle the line equation with errors-in-variables model,and in the parameter solution the coefficient matrix is divided into two parts by using the QR decomposition. And then the Related parameter can be achieved by the ordianary least squares and total least squares. A conclusion can be got that ling fitting by total least squares is more effective than that of ordianary least square on the whole.