Cramming:-
One Thursday, researchers gave students enrolled in a section of basic Spanish a set of 50 new vocabulary words to memorize. On Friday the students took a vocabulary test. When they returned to class the following Monday, they were retested - without advance warning. Both sets of test scores for the 25 students are shown.
|
Fri.
|
Mon.
|
Fri.
|
Mon.
|
Fri.
|
Mon.
|
|
42
|
36
|
48
|
37
|
39
|
41
|
|
44
|
44
|
43
|
41
|
46
|
32
|
|
45
|
46
|
45
|
32
|
37
|
36
|
|
48
|
38
|
47
|
44
|
40
|
31
|
|
44
|
40
|
50
|
47
|
41
|
32
|
|
43
|
38
|
34
|
34
|
48
|
39
|
|
41
|
37
|
38
|
31
|
37
|
31
|
|
35
|
31
|
43
|
40
|
36
|
41
|
|
43
|
32
|
|
|
|
|
a) What is the correlation between Friday and Monday scores?
b) What does a scatterplot show about the association between the scores?
c) What does it mean for a student to have a positive residual?
d) What would you predict about a student whose Friday score was one standard deviation below average?
e) Write the equation of the regression line.
f) Predict the Monday score of a student who earned a 40 on Friday.