Confidence Intervals
Example 2 (calculation with parameter)
Mean : 300
Sample size : 6
Population standard deviation : 3
Significance level : 5% ( = confidence level : 95%)
•Statistics Wizard Operation
(1)On the menu bar, tap [Calc] and then [Interval].
(2)Select
(3)Input values.
(4)Tap [Next >>].
uProgram, eActivity or Main Application
Command: OneSampleZInt
Command Syntax
Syntax 1 (list format)
* “Freq” can be omitted. Doing so sets “1” for “Freq”.
Syntax 2 (parameter format)
Input Example:
Syntax 1 (list format)
OneSampleZInt 0.95,3,list1,1
Syntax 2 (parameter format)
OneSampleZInt 0.95,3,300,6
Menu:
Description: This command obtains the confidence interval for the difference between population means when the population standard deviations of two populations are known.
The confidence interval is obtained using the following expressions.
The confidence level is 100 (1 – α)%.
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| o1 | : sample mean of sample 1 data | |||
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| σ 2 |
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Left = (o1 – o2) – Z |
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| o2 | : sample mean of sample 2 data | |||||
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| σ1 | : population standard deviation of |
Right = (o1 – o2) + Z |
| α |
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| σ12 | + | σ22 | σ2 | sample 1 | ||||||||
| 2 |
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| n1 | sample 2 |
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| : size of sample 1 | |
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| n2 | : size of sample 2 |
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