Setting simultaneous specifications on multiple raw materials to ensure product quality and minimize risk

Establishing meaningful multivariate specification regions on the multiple properties of a single raw material has been presented and illustrated by Duchesne & MacGregor Duchesne and MacGregor (2004) . However, the manufacture of most final products usually involves the use of many raw materials each with multiple measured properties and from different suppliers. Setting specifications separately on each of these materials is unreasonable since …