Confidence Intervals for the population proportion
(when n is large)
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To do this, enter your data into C1. Then go to Stat, Basic Statistics,
1 proportion.
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Your screen should look like this.
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Enter the summarized data. Enter n into the number of trials and enter
the number of successes.
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Make sure that you entered the correct confidence level.
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Enter the value of the hypothesis statement into the box next to test proportion.
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Next pick the alternative that matches your alternative hypotheses.
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Make sure that the box is checked for "Use test and interval based on normal
distribution".
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.
Test and CI for One Proportion
Test of p = 0.5 vs p not = 0.5
Sample X
N Sample p 95.0%
CI Z-Value P-Value
1 34
345 0.098551 (0.067099, 0.130002) -14.91
0.000