If the quality of teaching is similar in a school, the scores on a standardized test will have a standard deviation of 1616. The superintendent wants to know if there is a disparity in teaching quality, and decides to investigate whether the standard deviation of test scores has changed. She samples 2626 random students and finds a mean score of 166166 with a standard deviation of 17.982217.9822. Is there evidence that the standard deviation of test scores has increased at the α=0.005α=0.005 level? Assume the population is normally distributed.
Step 2 of 5 :
Determine the critical value(s) of the test statistic. If the test is two-tailed, separate the values with a comma. Round your answer to three decimal places.
Get Answers For Free
Most questions answered within 1 hours.