S
sturae
THE DATA ARE THE PERCENTAGE EXAMINATION MARKS (Y) AND TH
PERCENTAGE
ATTENDANCE AT CLASSES (X) FOR A GROUP OF 40 STUDENTS,
PERFORM A LINEAR REGRESSION OF Y ON X AND USE THIS TO DETERMINE TH
FOLLOWING
AMOUNTS.
INTERCEPT (a) 12.60463992
GRADIENT (b) 0.699961906
PREDICTED VALUE OF Y WHEN X = 60%
PREDICTED VALUE OF Y WHEN X = 0%
CORRELATION COEFFICIENT 0.81440364
COEFFICIENT OF DETERMINATION
ESTIMATED ATTENDANCE WHEN MARK = 50%
MARK % ATTENDANCE % WORKING AREA IF NEEDED
45 48
55 40
65 90
89 90
100 100
20 5
35 15
25 10
45 50
55 45
69 80
75 70
86 80
79 85
25 12
10 89
0 2
56 70
68 80
78 80
50 60
45 55
90 85
100 95
95 80
75 90
40 85
20 10
25 15
30 20
0 10
50 60
40 67
57 89
68 78
58 60
30 20
21 12
25 25
78 9
PERCENTAGE
ATTENDANCE AT CLASSES (X) FOR A GROUP OF 40 STUDENTS,
PERFORM A LINEAR REGRESSION OF Y ON X AND USE THIS TO DETERMINE TH
FOLLOWING
AMOUNTS.
INTERCEPT (a) 12.60463992
GRADIENT (b) 0.699961906
PREDICTED VALUE OF Y WHEN X = 60%
PREDICTED VALUE OF Y WHEN X = 0%
CORRELATION COEFFICIENT 0.81440364
COEFFICIENT OF DETERMINATION
ESTIMATED ATTENDANCE WHEN MARK = 50%
MARK % ATTENDANCE % WORKING AREA IF NEEDED
45 48
55 40
65 90
89 90
100 100
20 5
35 15
25 10
45 50
55 45
69 80
75 70
86 80
79 85
25 12
10 89
0 2
56 70
68 80
78 80
50 60
45 55
90 85
100 95
95 80
75 90
40 85
20 10
25 15
30 20
0 10
50 60
40 67
57 89
68 78
58 60
30 20
21 12
25 25
78 9