This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Stats for Strategy Fall 2008 HOMEWORK 5 (covers Topic 7, due Monday, Oct. 6) DIRECTIONS: • Use Four Steps . Extract the F statistic and P-value from MINITAB output for hy- pothesis tests. If an exercise does not specify a significance level, use α = . 05 . • Data sets for some exercises are available on the Data Sets link from the course website. (Remember to open data files as worksheets in MINITAB .) A. Homework Problems with Posted Solutions (8 problems) Notebook Exercises 1. (Branson steakhouses) Refer to page 57 in the Notebook. We calculated the statistic F = 2 . 0 from the Case 2 data for Example 1. (a) Use the MINITAB F distribution from Calc > Probability Distributions to find an exact P-value for the ANOVA hypothesis. Use all available decimal places. (Hint : Refer to Notes page 55 for information which MINITAB requires.) (b) We failed to reject the null hypothesis, even though F = 2 . > 1 What would the P-value have been had we calculated F = 1 . 0 instead of F = 2 . 0? 2. (More steakhouses) Refer to the Case 3 data for Example 1. (a) Calculate MSE = s 2 p with hand calculations, similar to our in-class calculations of s 2 p for Case 1 and Case 2 data. (b) The value MSG = 500 is the same as for Case 1 and Case 2 data since the sample means are ¯ x 1 = 100 ¯ x 2 = 110 ¯ x 3 = 120 Use your answer from (a) to calculate the F statistic. (c) Interpret your answer from (b). (d) Use MINITAB to calculate the exact P-value. (continued) 1 (e) Download the Topic 7 Example 1 MINITAB Demo (project) file. Open the file and follow the MINITAB steps shown on page 63 of the notes, except apply them to the Case 3 data instead of the Case 2 data. • What F statistic and P-value does MINITAB ANOVA produce? Are they the same values (except for rounding) which you calculated in (b) and (d)? • Did you produce the Tukey CI’s shown on page 66 and the graph shown on page 49? (The points on page 49 are “jiggled” horizontally so that they are not covered by the sample means in black-and-white print.) 3. (Practice with ANOVA tables) Suppose that the (partial) MINITAB ANOVA table for a set of data is Source DF SS...
View Full Document
- Fall '11
- Statistics, Statistical hypothesis testing