Question
In: Statistics and Probability
Question3: Consider the following 14 independent measurements from a normal distribution: Independent measurements 20 18 11...
Question3: Consider the following 14 independent measurements
from a normal distribution:
Independent measurements
20 18 11 20 16 14 15 15 14 13 11 18 20 9
1) What is the standard error of the sample mean?
0.9936
3.5826
0.9575
3.4303
2) Calculate a 99% confidence interval for the population
mean.
[5.8831,24.6883]
[12.9734,17.5980]
[12.4015,18.1700]
[12.7480,17.8234]
Solutions
Expert Solution
 |
 |
 |
| 20 | 4.7142857 | 22.22448980 |
| 18 | 2.7142857 | 7.36734694 |
| 11 | -4.2857143 | 18.36734694 |
| 20 | 4.7142857 | 22.22448980 |
| 16 | 0.7142857 | 0.51020408 |
| 14 | -1.2857143 | 1.65306122 |
| 15 | -0.2857143 | 0.08163265 |
| 15 | -0.2857143 | 0.08163265 |
| 14 | 1.2857143 | 1.65306122 |
| 13 | -2.2857143 | 5.22448980 |
| 11 | -4.2857143 | 18.36734694 |
| 18 | 2.7142857 | 7.36734694 |
| 20 | 4.7142857 | 22.22448980 |
| 9 | -6.2857143 | 39.51020408 |
 |
 |
a) The standard error of the sample mean
Answer: 0.9575
b) We need to construct the 99% confidence interval for the population mean μ.
The critical value for α=0.01 and df = n-1 =14-1= 13, tc= t1−α/2;n−1=3.012.
The corresponding confidence interval is computed as shown below:
Answer: (12.4015, 18.1700)
orchestra answered 2 years agoRelated Solutions
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Low Medium High 14 18 16 6 17 20 11 23 18 12 17 16 11...
Low
Medium
High
14
18
16
6
17
20
11
23
18
12
17
16
11
10
15
9
20
16
6
15
16
12
17
17
14
25
11
11
11
13
4
18
22
9
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7
20
10
12
21
18
12
27
9
17
13
19
11
22
16
8
17
12
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