Hunter design table

Table 5 L18 Hunter Design Table for the Qualification Study for the Coupled Heat-Inactivation/ Precipitation Steps... 

The fractional factorial is designed to reduce the number of qualification trials to a more reasonable number, say, 10, while holding the number of randomly assigned processing variables to a reasonable number as well, say, 9. The technique was developed as a nonparametric test for process evaluation by Box and Hunter [18] and reviewed by Hendrix [19]. Ten is a reasonable number of trials in terms of resource and time commitments and should be considered an upper limit in a practical testing program. This particular design as presented in Table 7 does not include interaction effects. 

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