Mixture Designs

Experimental Objective

This classic mixture example was discussed by Cornell (1990). A yarn is manufactured by blending three different materials, and the investigators are interested in the best blend for creating a fiber with maximum elongation. They use a simplex-lattice mixture design for the experiment. The investigators identified the following variables for the experiment shown in Table 10.1.

Table 10.1: Responses and Factors for Yarn Elongation Experiment

Variable	Name	Description
Factors	PRO	Polypropylene proportion
	ETH	Polyethylene proportion
	STY	Polystyrene proportion
Response	ELONG	Yarn elongation

The goal of the experiment is to maximize elongation and minimize prediction variance.

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Task List