11.(15 pts) A 2. factorial experiment was carried out to study the factors thought to influence the yield of a chemical process. Four factors are considered, they are: temperature (A), pressure (B), reactant amount (C). and stirring rate (D). The design matrix and the response are shown in Table 3. Table 3 - A B C D Yield 12 + + 18 13 16 17 15 20 15 10 25 13 24 19 21 17 23 + a. Among the effects of the main factors and their interactions, which effects appear to be large? Identify them and give their values. b. Conduct an analysis of variance including only the factors/interactions with large effects as you indicated. Give your conclusions. Is this a good model? c. Conduct an analysis of variance including only the main factor and their two-way interactions. Give your conclusions. Compare to the model you got in b, is this a better model? 11.(15 pts) A 2. factorial experiment was carried out to study the factors thought to influence the yield of a chemical process. Four factors are considered, they are: temperature (A), pressure (B), reactant amount (C). and stirring rate (D). The design matrix and the response are shown in Table 3. Table 3 - A B C D Yield 12 + + 18 13 16 17 15 20 15 10 25 13 24 19 21 17 23 + a. Among the effects of the main factors and their interactions, which effects appear to be large? Identify them and give their values. b. Conduct an analysis of variance including only the factors/interactions with large effects as you indicated. Give your conclusions. Is this a good model? c. Conduct an analysis of variance including only the main factor and their two-way interactions. Give your conclusions. Compare to the model you got in b, is this a better model