The application of evolving projection analysis (EPA) to second-order
bilinear data sets consisting of more than two components is described
. EPA is a method for rank analysis of ordered data matrices where the
components appear sequentially as a function of time or some other or
dinal variable. It was found that extension of the method to mixtures
of more than two components was best accomplished using principal comp
onents analysis to preprocess the data. The algorithm is demonstrated
using simulated four-component chromatographic data, and experimental
data from liquid chromatography (three- and four-component mixtures) a
nd a spectrophotometric titration (four components), both employing UV
-visible diode array detection.