00000cab a22000003a 4500 UP-99796217611235724 Buklod 20231008001402.0 a grb 001 u| ta 140429s xx d | ||r ||||| || DENG eng Vives-Mestres, Marina Individual T2 control chart for compositional data. pp. 127-139 The usual Hotelling T2 control chart is not appropriate for monitoring processes where the quality characteristic is a mixture. The composition of mixtures are vectors of positive elements that represent parts of a whole, to which standard multivariate techniques are not appropriate due to their restricted sample space. There are many applications where a mixture is monitored against time, such as in the chemical industry, product composition, impurity profile, or gas components analysis. In this paper, a multivariate control chart for individual compositional observations based on the T2 statistic is proposed and compared with the typical one in terms of average run length. We show how results are more consistent with compositional data nature and illustrate implementation in a real-world example. Average run length. Hotellings?s T2 Statistic. Log Ratio. Mixture Data. Multivariate Control Chart. Simplex. Statistical Process Control. Journal of Quality Technology 46, 2 (2014). FO UPD DENG Article