In: Statistics and Probability
4. A private-label bottler of soft drinks asks each of 60 members of a tasting panel (who are regarded as a random sample from millions of potential customers) to rate each of two possible formulations of a cola drink on a 100-point scale; higher scores are desirable. Formulation G is less expensive and will be used unless there is a clear evidence that formulation R is preferred. From the data, the bottler obtains the difference (R-G) in the ratings for each panelist. After conducting appropriate statistical tests on the mean of the differences in the ratings, the management of the private-label bottler concluded that the difference in the ratings is negligible. Consequently, they have decided to use formulation G which is less expensive. The data on the panelist’s ratings they have used is in the Excel data file named ‘Cola Ratings’. Using the same data and at 10% level of significance, please conduct the test you think the management’s decision must have been based on. Based on your results, do you agree with the management’s conclusion? Does your conclusion change at 5% level of significance?
G | R |
57 | 62 |
46 | 58 |
85 | 81 |
80 | 88 |
95 | 84 |
31 | 54 |
56 | 44 |
40 | 65 |
52 | 37 |
26 | 51 |
93 | 76 |
54 | 43 |
67 | 64 |
42 | 59 |
29 | 51 |
81 | 70 |
35 | 49 |
59 | 61 |
44 | 57 |
84 | 97 |
34 | 55 |
49 | 44 |
73 | 86 |
74 | 89 |
44 | 52 |
41 | 49 |
72 | 61 |
60 | 48 |
48 | 69 |
92 | 87 |
64 | 77 |
52 | 47 |
58 | 66 |
84 | 80 |
60 | 50 |
49 | 38 |
96 | 74 |
20 | 49 |
42 | 19 |
36 | 58 |
69 | 48 |
44 | 56 |
37 | 59 |
57 | 29 |
31 | 62 |
74 | 51 |
85 | 79 |
19 | 52 |
33 | 76 |
48 | 80 |
88 | 84 |
72 | 64 |
45 | 58 |
36 | 42 |
64 | 85 |
77 | 75 |
28 | 22 |
93 | 87 |
45 | 48 |
50 | 40 |
G | R | ||
Mean | 56.65 | Mean | 60.76666667 |
Standard Error | 2.702146562 | Standard Error | 2.26348647 |
Median | 53 | Median | 58.5 |
Mode | 44 | Mode | 58 |
Standard Deviation | 20.93073727 | Standard Deviation | 17.5328908 |
Sample Variance | 438.0957627 | Sample Variance | 307.4022599 |
Kurtosis | -0.937467288 | Kurtosis | -0.436751072 |
Skewness | 0.264852348 | Skewness | -0.033675571 |
Range | 77 | Range | 78 |
Minimum | 19 | Minimum | 19 |
Maximum | 96 | Maximum | 97 |
Sum | 3399 | Sum | 3646 |
Count | 60 | Count | 60 |
Based on your results, we agree with the management’s conclusion.
Does your conclusion change at 5% level of significance?
For a 5% level of significance.