In: Statistics and Probability
Estimate the population mean μ in two ways. (a) Give a point estimate for μ and a “margin of error”. (b) Construct a 99% confidence interval for μ (c) Approximately what kind of distribution does the random variable (x bar) have, and why? What is the name of the theorem that tells you so? Below is sample data: |
7.13 |
6.5 |
6.4 |
6.53 |
6.58 |
6.63 |
7.11 |
7.04 |
7 |
7.15 |
6.76 |
6.96 |
7.14 |
7.21 |
7.25 |
7.18 |
7.12 |
6.55 |
7.18 |
7.05 |
6.59 |
6.88 |
6.94 |
6.85 |
6.59 |
6.6 |
6.98 |
6.68 |
7.07 |
7.21 |
6.88 |
7.01 |
7.02 |
6.69 |
6.9 |
6.76 |
6.3 |
6.64 |
6.81 |
6.87 |
6.97 |
6.62 |
7.03 |
6.61 |
6.99 |
6.6 |
6.86 |
7.1 |
6.79 |
7.02 |
6.89 |
6.83 |
6.97 |
6.76 I calculated the mean is 6.8662 and standard dev. is 0.232, and sample size is 54 |
sr.no. | x | x-x̅ | (x-x̅)^2 |
1 | 7.13 | 0.2637 | 0.0695 |
2 | 6.5 | -0.3663 | 0.1342 |
3 | 6.4 | -0.4663 | 0.2174 |
4 | 6.53 | -0.3363 | 0.1131 |
5 | 6.58 | -0.2863 | 0.0820 |
6 | 6.63 | -0.2363 | 0.0558 |
7 | 7.11 | 0.2437 | 0.0594 |
8 | 7.04 | 0.1737 | 0.0302 |
9 | 7 | 0.1337 | 0.0179 |
10 | 7.15 | 0.2837 | 0.0805 |
11 | 6.76 | -0.1063 | 0.0113 |
12 | 6.96 | 0.0937 | 0.0088 |
13 | 7.14 | 0.2737 | 0.0749 |
14 | 7.21 | 0.3437 | 0.1181 |
15 | 7.25 | 0.3837 | 0.1472 |
16 | 7.18 | 0.3137 | 0.0984 |
17 | 7.12 | 0.2537 | 0.0644 |
18 | 6.55 | -0.3163 | 0.1000 |
19 | 7.18 | 0.3137 | 0.0984 |
20 | 7.05 | 0.1837 | 0.0337 |
21 | 6.59 | -0.2763 | 0.0763 |
22 | 6.88 | 0.0137 | 0.0002 |
23 | 6.94 | 0.0737 | 0.0054 |
24 | 6.85 | -0.0163 | 0.0003 |
25 | 6.59 | -0.2763 | 0.0763 |
26 | 6.6 | -0.2663 | 0.0709 |
27 | 6.98 | 0.1137 | 0.0129 |
28 | 6.68 | -0.1863 | 0.0347 |
29 | 7.07 | 0.2037 | 0.0415 |
30 | 7.21 | 0.3437 | 0.1181 |
31 | 6.88 | 0.0137 | 0.0002 |
32 | 7.01 | 0.1437 | 0.0207 |
33 | 7.02 | 0.1537 | 0.0236 |
34 | 6.69 | -0.1763 | 0.0311 |
35 | 6.9 | 0.0337 | 0.0011 |
36 | 6.76 | -0.1063 | 0.0113 |
37 | 6.3 | -0.5663 | 0.3207 |
38 | 6.64 | -0.2263 | 0.0512 |
39 | 6.81 | -0.0563 | 0.0032 |
40 | 6.87 | 0.0037 | 0.0000 |
41 | 6.97 | 0.1037 | 0.0108 |
42 | 6.62 | -0.2463 | 0.0607 |
43 | 7.03 | 0.1637 | 0.0268 |
44 | 6.61 | -0.2563 | 0.0657 |
45 | 6.99 | 0.1237 | 0.0153 |
46 | 6.6 | -0.2663 | 0.0709 |
47 | 6.86 | -0.0063 | 0.0000 |
48 | 7.1 | 0.2337 | 0.0546 |
49 | 6.79 | -0.0763 | 0.0058 |
50 | 7.02 | 0.1537 | 0.0236 |
51 | 6.89 | 0.0237 | 0.0006 |
52 | 6.83 | -0.0363 | 0.0013 |
53 | 6.97 | 0.1037 | 0.0108 |
54 | 6.76 | -0.1063 | 0.0113 |
Total | 370.78 | 2.8733 | |
mean=x̅ | Total/54 | ||
x̅= | 6.8663 |