Multivariate Monitoring with GPS Observations and Auxillary Multisensor Data

In a multisensor measurement or monitorin environment, p variables are measured simultaneously. The measured data are correlated and can be monitored to identify special causes of variation in order to establish control and to obtain reference samples to use as a basis in determining the control limits for future observations. One common method is to construct a multivariate control chart based on Hotelling's T2 statistic. When the monitoring process is at the start-up stage, F and chi-square distributions are used to construct the necessary control limits. An example from a seven-day GPS data sample measured concurrently with the accelerometer response, wind velocity and temperature illustrates that this technique can improve the interpretation of GPS results. Moreover, the computational complexity is reduced through a reduction in the data dimensionality. © 2002 Wiley Periodicals, Inc.