Question

Question 4 (18 points) The article 'Effect of Refrigeration on the Potassium Bitartrate Stability and Composition of Italian Wines' (A. Versari, D. Barbanti, et al., Italian Journal of Food Science, 2002:45-52) reports a study in which 9 types of wine had their tartaric acid concentration (in g/L) measured both before and after a cold stabilization process. The results are presented in the following table: >3E-DOO Wine Type Before After 1.34 1.71 2.33 1.28 2.05 1.38 0.75 1.28 2.94 2.56 0.94 2.38 1.77 1.51 2.53 0.90 2.07 2.32 The researchers are interested in whether there is evidence that the average tartaric acid concentration for all wine types differs, depending on whether or not wine undergoes a cold stabilization process. a) (4 points) What is the blocking variable in this study? Also, what is the factor of interest? b) (4 points) State the appropriate hypotheses for this study. c) (10 points) Let's say that the assumptions for the F-test are reasonable. Conduct the appropriate test. Report the p-value, decision, and conclusion, in context. Assume the significance level is a=0.05.

Answer 1

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