Grades and AM/PM Section of Stats: There weretwo large sections of statistics this term at State College, an8:00 (AM) section and a 1:30 (PM) section. The final grades forboth sections are summarized in the contingency table below.
Observed Frequencies:Oi's
| | | | | | |
| A | B | C | D | F | Totals |
AM | 6 | 11 | 19 | 18 | 17 | 71 |
PM | 19 | 20 | 18 | 12 | 8 | 77 |
Totals | 25 | 31 | 37 | 30 | 25 | 148 |
The Test: Test for a significant dependentrelationship between grades and the section of the course. Conductthis test at the 0.05 significance level.
(a) What is the null hypothesis for this test?
H0: The section (AM/PM) of a course and thegrades are independent variables. H0: Thesection (AM/PM) of a course and the grades are dependentvariables.
(b) What is the value of the test statistic? Round to 3decimal places unless your software automatically rounds to 2decimal places.
?2
=
(c) Use software to get the P-value of the test statistic.Round to 4 decimal places unless your softwareautomatically rounds to 3 decimal places.
P-value =
(d) What is the conclusion regarding the null hypothesis?
reject H0fail to rejectH0
(e) Choose the appropriate concluding statement.
We have proven that grades and section of the course areindependent.The evidence suggests that there is a significantdependent relationship between grades and the section of thecourse. There is not enough evidenceto conclude that there is a significant dependent relationshipbetween grades and the section of the course.