Posted by **jack ** on Monday, December 19, 2011 at 2:44pm.

o test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of 24.9. Is this a significant difference at α = .05? (a) State the hypotheses for a right-tailed test. (b) Obtain a test statistic and p-value assuming equal variances. Interpret these results. (c) Is the difference in mean scores large enough to be important? (d) Is it reasonable to assume equal variances? (e) Carry out a formal test for equal variances at α = .05, showing all steps clearly.

## Answer This Question

## Related Questions

- statistics - To test the hypothesis that students who finish an exam first get ...
- res/342 - To test the hypothesis that students who finish an exam first get ...
- math - Jenny must sit four papers for an exam. The mean of the first three ...
- statistics - a study of 40 professors showed they spent on average 13.6 minutes ...
- statistics - A professor is interested in the relationship between the number ...
- math - On a certain exam, Tony corrected 10 papers and found the mean for his ...
- math - A college professor has 370 papers to grade. In one evening, she grades ...
- English Ms Sue - Ok, I got my final exam in hand. Nine pages. Think I can whip ...
- graduate statistics - A nursing professor was curious as to whether the students...
- statistics - SAT Exam Scores – A school administrator wonders if students whose ...

More Related Questions