
MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Transcribed Image Text:Does a statistics course improve a student's mathematics skills,as measured by a national test? Suppose a random sample of 13 students takes the same national mathematics exam prior to enrolling in a stats course and just after completing the course. At a 1% level of significance determine whether the scores after the stats
course are significantly higher than the scores before. Take the differences = before - after.
Before After
430
465
485
475
520
535
360
410
440
425
500
505
425
450
470
480
515
520
430
430
450
460
495
500
540
530
What type of alternative hypothesis is appropriate for this research question?
O one-sided
O two-sided
Locate student 9 in the dataset. What rank will be given to this student?
What is the value of the test statistic, T? Give answer to 1 decimal place.
What is the critical value for the study? (Hint: student 10 will be dropped from the analysis, since the scores are the same before and after the stats class).
Are the exam scores significantly higher after the stats course?
O Yes
O No
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