Four materials: A, B, C and D are added in a blend to achieve a desired heat capacity, the response variable, y.
The amounts were varied in a factorial manner for the 4 materials.
The data are scaled and coded for confidentiality. All that may be disclosed is that variable C is either added ("Yes") or not added not added ("No").
A data.frame containing 19 observations of 5 variables (A, B, C, D, and the response, y)
Kevin Dunn, data from a confidential industrial source.