In: Statistics and Probability
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Random sampling from four treatments produced the following data: Use Table 4. |
| Click here for the Excel Data File |
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Treatments |
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| A | B | C | D |
| −11 | −8 | −8 | −12 |
| −13 | −13 | −13 | −13 |
| −10 | −15 | −8 | −15 |
| −12 | −13 | ||
| −10 | |||
| X−AX−A = −11.3 | X−BX−B = −12 | X−CX−C = −10.4 | X−DX−D = −13.3 |
| sA2 = 2.33 | sB2 = 8.7 | sC2 = 6.3 | sD2 = 2.3 |
| a. |
Calculate the grand mean. (Negative value should be indicated by a minus sign. Round your answer to 1 decimal place.) |
| Grand mean |
| b. | Calculate SSTR and MSTR. (Round intermediate values to 4 decimal places and final answers to 2 decimal places.) |
| SSTR | |
| MSTR | |
| c. | Calculate SSE and MSE. (Round intermediate values to 4 decimal places and final answers to 2 decimal places.) |
| SSE | |
| MSE | |
| d. | Specify the competing hypotheses in order to determine whether some differences exist between the population means. | ||||||
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| e. | Calculate the value of the F test statistic. (Round your answer to 2 decimal places.) |
| F test statistic |
| f. | Approximate the p-value. | ||||||||
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| g. | At the 10% significance level, what is the conclusion to the test? | ||||
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Solution: We can use the excel ANOVA: Single Factor data analysis tool to find the answer to the given questions. The excel steps are given below:
Enter the data in excel as:

Click on Data > Data Analysis > ANOVA: Single Factor > OK
Input Range: Select all the data ranges here.
Mark the Labels
Alpha: 0.10
Press Ok. The excel output is given below:
| Anova: Single Factor | |||||
| SUMMARY | |||||
| Groups | Count | Sum | Average | Variance | |
| A | 3 | -34 | -11.33 | 2.33 | |
| B | 4 | -48 | -12.00 | 8.67 | |
| C | 5 | -52 | -10.40 | 6.30 | |
| D | 3 | -40 | -13.33 | 2.33 | |
| Grand Mean | -11.8 | ||||
| ANOVA | |||||
| Source of Variation | SS | df | MS | F | P-value |
| Between Groups | 17.07 | 3 | 5.69 | 1.03 | 0.415 |
| Within Groups | 60.53 | 11 | 5.50 | ||
| Total | 77.6 | 14 |
a. Calculate the grand mean.
Answer:

