Hypothesis Test for mu (when sigma is unknown)
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When sigma is unknown, and n>40, you want to conduct a HT that uses
z.
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To do this, enter your data into C1. Then go to Stat, Basic Statistics,
1 sample z.
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Your screen should look like this.
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Enter the variable that you want and enter the sample standard deviation
as sigma.
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Enter the value of mu in your hypothesis statement.
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Now click on Options.
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Do not worry about the blank for the confidence level.
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Next pick the alternative that matches your alternative hypothesis.
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If you want a two sided test, select "not equal" as your alternative.
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If you want a one sided test, , select "less than" or "greater
than".
Note: Your screen may look a little different; however,
you should have the same boxes to fill in for Confidence and Alternative.
Your output may look like the following.
One-Sample Z: C2
Test of mu = 6 vs mu < 6
The assumed sigma = 0.3
Variable N
Mean StDev SE Mean
C2
40 5.6258 7.3789
0.0474
Variable 95.0% Upper Bound
Z P
C2
5.7038
-7.89 0.000