A graphical criterion to examine the quality of multicomponent analysis

A graphical criterion approach has been developed to examine the quality of a set of sensors in multicomponent analysis. Criteria such as sensitivity and selectivity, used in wavelength selection problems, can be explained in terms of the confidence interval of the estimated concentrations. These confidence intervals describe (hyper)ellipsoids whose volume, shape and orientation are related to the optimization criteria. The effect of sensor selection on these criteria is discussed and guidelines for wavelength selection are given. The usefulness of the graphical criterion is shown in the simultaneous determination of 2-chlorophenol and 2,4-dichlorophenol in water.