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Question
NARRBEGIN: SA_86_90A statistics professor has just given the final examination in his introductory statistics course. In particular, he is interested in learning how his class of 50 students performed on this exam. The data are shown below.
| 78 | 72 | 73 | 75 | 79 | 72 | 75 | 77 | 71 | 78 |
| 83 | 84 | 71 | 81 | 82 | 79 | 71 | 73 | 89 | 74 |
| 75 | 93 | 74 | 88 | 83 | 90 | 82 | 79 | 62 | 73 |
| 88 | 76 | 76 | 76 | 80 | 84 | 84 | 91 | 70 | 76 |
| 74 | 68 | 80 | 87 | 92 | 84 | 79 | 80 | 91 | 74 |
(A) Using these 50 students as the frame, use Excel to generate a simple random sample of size 10 from this frame.
(B) Compute the mean scores in the frame and the simple random sample you generated in (A).
(C) Compare the mean scores you computed in (B). Is your simple random sample a good representative of the frame? Why or why not?
(D) Using these 50 students as the frame, use Excel to generate a systematic sample of size 10 from this frame.
(E) Compare the mean scores in the frame with that in the systematic sample in (D). What do you conclude?
Answer
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