Table of Contents
What does the 99% confidence interval mean?
With a 95 percent confidence interval, you have a 5 percent chance of being wrong. With a 90 percent confidence interval, you have a 10 percent chance of being wrong. A 99 percent confidence interval would be wider than a 95 percent confidence interval (for example, plus or minus 4.5 percent instead of 3.5 percent).
Is a 99% confidence interval good?
Apparently a narrow confidence interval implies that there is a smaller chance of obtaining an observation within that interval, therefore, our accuracy is higher. Also a 95% confidence interval is narrower than a 99% confidence interval which is wider. The 99% confidence interval is more accurate than the 95%.
What does 99% confidence mean in a 99% confidence interval quizlet?
Hence a 99% confidence level means that 99 percent of all confidence intervals contain the population proportion or 99 percent of all samples or sample proportions will give you a confidence interval that contains the population proportion or we’re 99 confident that the confidence interval contains the population …
How can a 99% confidence interval estimate can be interpreted?
A 99% confidence interval estimate can be interpreted to mean that: If all possible samples are taken and confidence interval estimates are developed, 99% of them would include the true population mean somewhere within their interval. In practice, the population mean is the unknown quantity that is to be estimated.
What is the critical value for 99 confidence interval?
2.576
Thus Zα/2 = 1.645 for 90% confidence. 2) Use the t-Distribution table (Table A-3, p. 726). Example: Find Zα/2 for 98% confidence….
| Confidence (1–α) g 100% | Significance α | Critical Value Zα/2 |
|---|---|---|
| 90% | 0.10 | 1.645 |
| 95% | 0.05 | 1.960 |
| 98% | 0.02 | 2.326 |
| 99% | 0.01 | 2.576 |
What does 95% confidence mean in a 95% confidence interval quizlet?
A range of possible values for the population mean that is centered about the sample mean. What does a 95% confidence interval indicate? That you are 95% confident that the population mean falls within the confidence interval.
What is the 99% confidence interval estimate for the difference in the two means?
Because you want a 95 percent confidence interval, your z* is 1.96….Creating a Confidence Interval for the Difference of Two Means with Known Standard Deviations.
| Confidence Level | z*-value |
|---|---|
| 95% | 1.96 |
| 98% | 2.33 |
| 99% | 2.58 |
What is the primary purpose of a confidence interval for a mean?
A confidence interval for a mean gives us a range of plausible values for the population mean. If a confidence interval does not include a particular value, we can say that it is not likely that the particular value is the true population mean.