Sharp EL-512 - Page 25

X =
y-
Estimated value (the value of x is estimated from that of y .)
u
y y' = a + bx Estimated value (the value of y is estimated from that of x .)
® Data for two-variable statistic calculations are inputted by the following operations.
(1) Data ix) Data iy) [daw]
(2) Data (x) Data (y ) [X] Frequency [daw]
Example: If we know a student's mark in mathematics, can we predict the mark if1
English?
The exam marks for six students chosen at random are given in the following
table:
Mode: STAT, Floating decimal point system
Student No.
n
Mark in Math.
X
Mark in English
Y
1
82
79
2 53 50
3 61
87
4 74
96
5 51 73
6 51
73
Key in:
Display
82
79
[daw] 1
53
s
50 [daw]
2
61 87 [data]
3
74
s
96
|daw]
4
51 73 x 2 [daw]
6 (Note: to input multiple identical
s
i s
.571587901
samples proceed as indicated)
s
34.26190476
s
t s
.678571429
value of r of .57 indicates that the correlation is marginal. The equation for the
straight line for this data is Y = 34.26 + .68X.
' we had a student whose mark in mathematics was 90, based on this analysis, what mark
^ould the student have in English?
90 (2ndFl [y] 95.33333333
If
we had a student whose mark in English was 80, based on this analysis, what mark would
student have in mathematics?
80 0 0 67.40350877
47