How an input series enters the model is called its transfer function. Thus, ARIMA models with input series are sometimes referred to as transfer function models. In the preceding regression and ...

Daniel E. Wulbert, The Rational Approximation of Real Functions, American Journal of Mathematics, Vol. 100, No. 6 (Dec., 1978), pp. 1281-1315 ...

A mutually orthogonal system of rational functions on the whole line is introduced. Some approximation results are established. As an example of applications, a modified Legendre rational spectral ...