Agriculture Reference
In-Depth Information
Examples 8.24.
Given below are the plant height
(cm) and the no. of fruits per plant in eight varieties
of lady fingers. Find out whether the height and the
weight of the boys are correlated or not.
Height (
X
)
205
206
208
207
209
207
210
212
No of fruit (
Y
)
70
71
75
68
75
71
72
74
P
n
i¼
1
x
i
y
i
xy
1
n
At first, we calculate the following quantities:
1
n
r
xy
¼
s
1
n
n
i¼
1
x
i
P
n
i¼
1
y
i
8
X
8
X
8
8
1
1
2
x
2
2
y
2
x ¼
1
x
i
¼
208
;
y ¼
1
y
i
¼
72
:
i¼
i¼
3
5
p
¼
¼
0
:
527
:
ð
:
143
Þ
ð
6
:
286
Þ
We have
So the correlation coefficient between the
height and weight of 8 boys of class nine is 0.603.
X
n
i¼
1
x
i
x
8
X
n
1
n
1
ð
i
Þ
Cov
x; ðÞ¼
ð
Þ y
i
y
ð
Þ¼
i¼
1
x
i
y
i
xy ¼
3
!
Example 8.25.
Using the same problem given in
Example 8.21, we shall try to get the correlation
coefficients among the variables using MS Excel,
SPSS, and SAS as shown in the following slides:
(a) Using MS Excel software
X
n
i¼
1
x
i
x
X
n
i¼
1
x
i
1
n
1
n
2
x
¼
2
2
2
ð
ii
Þ
s
ð
Þ
¼
x
¼
5
:
143
!
X
n
i¼
1
y
i
y
X
n
i¼
1
y
i
1
n
1
n
2
2
y
¼
2
2
ð
iii
Þ
s
ð
Þ
¼
y
¼
6
:
286
Slide 8.17: Step 1 showing the entered or transferred data and selection of Correlation Analysis menu in MS Excel work
sheet
