Discussion:
Q: Opinion poll perfomed on 2 different population sizes, 900 and 10,000 with a 95% confidence level (Confidence Interval details have been computed) for each population.
a) The upper and lower limits from the confidence intervals only deviate from the proportion by 3, suggesting that citizens are indeed in favor of the viewpoint.
b) When using a larger sample size, the standard error is much smaller, as is the difference between the lower and upper limits. Therefore, this is more even more convincing than the smaller sample size.
Q: How many people would you have to survey to be 99% confident that you can estimate the fraction of people who believe the US Governement received invalid intelligence details to fund military operations in the middle east.
| Opinion Poll |
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| Surveyed |
900 |
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Surveyed |
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10000 |
| Invalid intelligence |
52% |
468 |
Invalid Intelligence |
52% |
| Proportion |
0.52 |
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Proportion |
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0.52 |
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| Confidence Interval |
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Confidence Interval |
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| Confidence level |
95% |
|
Confidence level |
95% |
| Standard error |
0.017 |
|
Standard error |
0.005 |
| z-multiple |
1.96 |
|
z-multiple |
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1.96 |
| Lower limit |
0.49 |
|
Lower limit |
0.51 |
| Upper limit |
0.55 |
|
Upper limit |
0.53 |