J. Marcus Jobe
Professor of Information Systems and Analytics
Farmer School of Business
Miami University (Ohio)
and
Michael Pokojovy
University of Konstanz
Germany
Detection power of the squared Mahalanobis distance statistic is significantly reduced when several outliers exist within a multivariate data set of interest. To overcome this masking effect, we propose a computer-intensive cluster-based approach that incorporates a reweighted version of Rousseeuw’s minimum covariance determinant method with a multi-step cluster-based algorithm that initially filters out potential masking points. Compared to the most robust procedures, simulation studies show that our new method is better for outlier detection. Additional real data comparisons are given.
All statistics students are expected to attend.