Memory deteriorates over time. A researcher is interested in discovering a difference between males and females regarding memory retention.

Memory deteriorates over time. A researcher is interested in discovering a difference between males and females regarding memory retention. He gathered 10 males and 10 females and had each complete a series of memory tests. He then recorded the overall scores for each participant, as shown below. The researcher ultimately believes that Females will retain more memory, and thus score higher on the tests, than males.

Females        Males
77                    87
88                    77
77                    71
90                    70
68                    63
74                    50
62                    58
93                    63
82                    76
79                    65

a. State in words what your H1 and H0 would be.

b. What kind of test would you use (i.e. Related-Samples t-test, z-test, etc.)?

c. What is your df? What is your critical t?

d. Calculate t.

e. Based on the above information, would you reject H0, or fail to reject it? Why? How would you state your conclusion in words?

3. College sophomores were given a Math achievement test before and after undergoing a weeklong supplemental instruction course. Based on the scores below, is it reasonable to conclude that the course had a significant impact on student math scores?

Participant Before After
        A                20           18
        B                18        22
        C                17           15
        D                16           17
        E                12             9
        F                19           15
        G                20           23
        H                  9           14

a. State symbolically what your H1 and H0 would be.

b. What kind of test would you use (i.e. Related-Samples t-test, z-test, etc.)?

c. What is your df? What is your critical t?

d. Calculate t.

e. Based on the above information, would you reject H0, or fail to reject it? Why? How would you state your conclusion in words?

Expert Solution

orchestra answered 2 years ago

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