Question

These problems may be solved using Minitab. Copy and paste the appropriate Minitab output into a word-processed file. Add your explanations of the output near the Minitab output. DO NOT SIMPLY ATTACH PAGES OF OUTPUT AS AN APPENDIX.

Each problem should be able to fit on one or two pages, and each problem should include the following:

• Minitab output for the ANOVA.
• Written statement interpreting the ANOVA.
• Four-in-one plot of the residuals.
• Written interpretation as to whether the three assumptions of the ANOVA were met.
• Tukey comparisons if necessary.
• A written summary of your interpretation of the analysis in terms of the problem. This may involve more than one statement. In other words, state which group is “best” in terms of the problem.

1. Battery life for competing smartphone designs are being studied. 5 models of phone were fully charged and set to play the same video on repeat (the volume and brightness levels were to the same levels using laboratory instruments). The test was replicated 10 times for each phone, with the time until the phone turned off recorded (in hours). Analyze this problem as a CRD ANOVA to determine if the phone models differ in their battery life, and how they differ. If they are necessary, perform Tukey comparisons using Minitab AND BY HAND.

Design 1	Design 2	Design 3	Design 4	Design 5
12.2	12.2	10.0	10.2	11.0
12.4	13.4	11.2	7.9	12.5
11.9	12.4	8.9	9.1	11.7
11.7	11.0	11.2	11.2	10.8
11.7	12.4	10.2	10.1	10.0
12.0	13.1	10.6	6.6	9.8
11.8	11.5	10.4	8.1	10.3
11.5	11.6	9.2	10.0	9.3
13.9	13.3	10.8	8.7	11.1
13.2	12.7	11.5	8.4	12.9

Answer 1

stat -> anova -> one way

selct response are in separate column for each factor level

Minitab output

since p-value = 0.814 > alpha

we fail to reject the null hypothesis

we conclude that there is not significant difference in mean

residuals plots

It looks like all assumptions are met,