Suppose the salinity of water samples taken from 3 new and separate sites in the Bimini Lagoon was measured with the results given below:
Site 1: 51.94 51.95 57.02 52.47 49.50 47.23 43.78 51.97
52.23
Site 2: 59.47 59.48 64.47 59.99 57.07 54.83 51.43 59.50
Site 3: 50.61 50.63 55.80 51.16 48.13 45.81 42.28 50.65 50.91
Basic Statistics for the 3 samples:
Level | N | Mean | SD |
1 | 9 | 50.90 | 3.73 |
2 | 8 | 58.28 | 3.89 |
3 | 9 | 49.55 | 3.81 |
One-way ANOVA output:
Source | DF | SS | MS | F | P |
Factor | 2 | 367.55 | 183.78 | 12.68 | 0.0002 |
Error | 23 | 333.36 | 14.49 | ||
Total | 25 | 700.91 |
Using the data above, construct simultaneous (1−α*)100% confidence intervals for the pairwise differences in means using the Bonferroni procedure. Use an overall experiment-wide α = 0.05.
What is the value of α*? Answer: 0.0167
The critical t-value has a student's t distribution with how many degress of freedom? Answer: 23
What is the critcal t-value? Answer: 2.5820
1. Calculate the confidence interval for the difference in means for Levels 1 and 2, i.e., μ1−μ2.
2. What is your conclusion about the relative size of
the means for Levels 1 and 2?
μ1 ≤ μ2
μ1 ≠ μ2
μ1 = μ2
μ1 > μ2
3. Calculate the confidence interval for the difference in means for Levels 1 and 3, i.e., μ1−μ3.
4. What is your conclusion about the relative size of
the means for Levels 1 and 3?
μ1 = μ3
μ1 ≠ μ3
μ1 > μ3
μ1 < μ3
5. Calculate the confidence interval for the difference in means for Levels 2 and 3, i.e., μ2−μ3
6. What is your conclusion about the relative size of
the means for Levels 2 and 3?
μ2 ≠ μ3
μ2 > μ3
μ2 ≤ μ3
μ2 = μ3
Suppose the salinity of water samples taken from 3 new and separate sites in the Bimini...
Suppose the salinity of water samples taken from 3 new and separate sites in the Bimini Lagoon was measured with the results given below: Site 1: 49.59 49.60 54.11 50.06 47.42 45.40 42.32 Site 2: 54.66 54.67 59.74 55.19 52.22 49.95 46.50 54.69 54.95 45.04 54.88 54.02 Site 3: 45.65 45.66 50.72 46.18 43.22 40.95 37.50 45.68 45.94 36.05 45.87 Basic Statistics for the 3 samples: Level N Mean SD 1 7 48.36 3.77 2 12 53.04 4.07 3 11...
To test whether the mean time needed to mix a batch of material is the same for machines produced by three manufacturers, a chemical company obtained the following data on the time (in minutes) needed to mix the material. Manufacturer 1 2 3 20 28 20 25 25 18 24 32 24 27 27 18 (a) Use these data to test whether the population mean times for mixing a batch of material differ for the three manufacturers. Use α =...
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