Introduction to Probability and Statistics for Engineers and Scientists

250 Chapter 7: Parameter Estimation

The 95% confidence interval for the mean is (60.865, 77.6683)

Confidence Interval: Unknown Variance

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(a)

One-Sided

Two-Sided

Upper

Lower

Enter the value of a:

(0 < a < 1)

.05

Data value = 77 54

63

58

72

49

92

70

Sample size = 15

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The 95% lower confidence interval for the mean is (-infinity, 76.1662)

Confidence Interval: Unknown Variance

Start

Quit

(b)

One-Sided

Two-Sided

Upper

Lower

Enter the value of a:

(0 < a < 1)

.05

Data value = 77 54

63

58

72

49

92

70

Sample size = 15

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Data Values

Clear List

FIGURE 7.3 (a) Two-sided and (b) lower 95 percent confidence intervals for Example 7.3f.