Now that we have the standard error and z critical value, we can calculate the margin of error. Margin of error (E): E = z* . (standard error) Let's break down the margin of error. The margin of error is the width of the confidence interval and is comprised to two parts: p(1 - p) Standard error: A measure of the sample-to-sample variability, n *: The z critical value; this is the point on the standard normal distribution such that the proportion of area under the curve between - > * and + 2* is C, the confidence level. Calculate the margin of error that would be used to create a 95% confidence interval for the population proportion of students who had a high level of stress. Round to four decimal places. Hint Use your answers from Questions 6 and 7. Remember the z critical value is positive Question Help: Message instructor Calculator Submit Question1 _ in place of M. This Recall that when the sample size is large enough, we can use 71 is called the standard error, which is the estimated standard deviation of sample proportions. It is the measure of sample-to-sample variability. We will use the standard error to help us convey information about the accuracy of our point estimate! Score on last try: 1 of1 pts. See Details for more. > Next question Calculate the estimated standard deviation for the sample proportion for the scenario in Question 1. Round your answer to 2 decimal places. 003 J at6 Question Help: 8 Message instructor Calculator Submit Question Use the Find Percentile/Quantile tab of the DCMP Normal Distribution tool to find the z critical value, z* , for the most common confidence levels seen below. Round to the hundredths place. Hint Since you are looking at the standard normal distribution, you will keep the mean at 0 and the standard deviation at 1. You will need to use the two-tailed option. Confidence Level, C 2 * 90% +1.645 x 0 1.65 95% 1.96 99% 2.57 x 0 2.58