TRUE OR FALSE 1. A t-test is used when the population standard deviation is known. 2....

TRUE OR FALSE

1. A t-test is used when the population standard deviation is known.

2. The degrees of freedom in a t-test is one less than the margin of error.

3. A confidence interval can only be found when the standard deviation of the population is known.

4. The margin of error for a t-test is calculated using the sample mean.

5. The null hypothesis is a claim made about the sample.

6. The significance level is denoted by n.

7. If the conclusion of a hypothesis test is “fail to reject the null hypothesis,” then the results are statistically significant.

8. A 95% confidence interval for a population mean must be calculated using the sample mean.

9. A z-score is a test statistic.

10. A t-statistic is the same for a 95% confidence interval and a 90% confidence interval regardless to the same size.

Expert Solution

milcah answered 6 months ago

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