• bivariate control chart;
  • Hotelling's T2 statistic;
  • masking effect;
  • outliers;
  • robust estimation;
  • simulation study;
  • statistical process control

In this paper, we proposed a new bivariate control chart denoted by inline image based on the robust estimation as an alternative to the Hotelling's T2 control chart. The location vector and the variance-covariance matrix for the new control chart are obtained using the sample median, the median absolute deviation from the sample median, and the comedian estimator. The performance of the proposed method in detecting outliers is evaluated and compared with the Hotelling's T2 method using a Monte-Carlo simulation study. A numerical example is considered to illustrate the application of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.