© 1985 by Biometrika Trust
On the frequency domain estimation of the innovation variance of a stationary univariate time series
Department of Mathematical Sciences, University of Tampere Tampere, SF-33101, Finland
Department of Statistics, University of Umeå Umeå, S-901 87, Sweden
The innovation variance
2 of a linear stochastic time series model can be estimated using periodogram ordinates. However, since the periodogram ordinates as estimators of the corresponding spectrum ordinates can show appreciable small-sample bias, it is believed that the estimator of
2 is biased. One way of reducing the small-sample bias in the periodogram ordinates is by tapering. In this paper an estimator of
2 based on tapered time series is defined and evaluated analytically as well as by simulation. Tapering has a large bias-reducing as well as variance-reducing effect when the roots of the characteristic equation of the model are close to the unit circle.
Key Words: Bias Innovation variance Periodogram Stationary time series Tapering