J. Chen et al., ROBUST ESTIMATION OF MEASUREMENT ERROR VARIANCE COVARIANCE FROM PROCESS SAMPLING DATA/, Computers & chemical engineering, 21(6), 1997, pp. 593-600
Classical approaches to variance/covariance estimations are very sensi
tive to outliers. In the present paper a robust approach, based on an
M-estimator, is proposed. Monte Carlo simulations show that the strate
gy provides better results than conventional indirect methods under th
e presence of outliers. Two examples of application are provided; deal
ing with both uncorrelated and correlated errors. (C) 1997 Elsevier Sc
ience Ltd.