Partial order methodology: a valuable tool in chemometrics

Abstract

Often from multi‐indicator system (MIS), a composite indicator is derived by applying weighted sums of the single indicators. The eventual ranking being based on composite indicator yields a total (linear) ranking. In contrast, partial order ranking constitutes an alternative approach where assumptions about linearity or distribution of the indicators are not needed and indicators are in general used without quantification of mutual preferences. The present paper describes analyses of MIS based on a series of partial order techniques as offered by the PyHasse software. The paper describes how important information on an MIS can be obtained without lengthy and often controversial and possible subjective discussions about indicator weights and thus avoiding both covering up valuable information contained in the single indicators as well as unwanted compensation effects. The application of partial order for obtaining chemometric information is illustrated by a study of 12 chloro‐organic pesticides. All calculation has been carried out applying the experimental software PyHasse. Copyright © 2013 John Wiley & Sons, Ltd.