Consider the experiment in Exercise 14-16. Suppose that a center point with five replicates is added to the factorial runs and the responses are 2800, 5600, 4500, 5400, 3600. Compute an ANOVA with the sum of squares for curvature and conduct an F-test for curvature. Use α = 0.05.

Exercise 14-16

The following data represent a single replicate of a 25 design that is used in an experiment to study the compressive strength of concrete. The factors are mix (A), time (B), laboratory (C), temperature (D), and drying time (E).

= 700 = 900 = 3400 (1) 800 = 1200 ae abe = 6200 ab = 5500 = 600 = 1000 ce ac 1200 ace