The value needed to determine a confidence interval for a sample mean is: B. the standard error of the mean.
How to find the confidence interval for a sample mean?
To calculate a confidence interval for the mean, we need to know:
- the point estimate.
- the critical values for the test statistic
- the standard deviation of the sample
- the sample size.
The standard error of the mean is a measure of the variability of the sample mean and is calculated by dividing the sample standard deviation by the square root of the sample size.
The confidence interval is then calculated by adding and subtracting the margin of error from the sample mean, where the margin of error depends on the degree of confidence required for the estimation and is a function of the standard error of the mean and the critical value of the test statistic.