Example The two regression equations of the variables x
an y are
x = 19.13  0.87 y and y = 11.64  0.50 x
Find (1) Mean of x’s
(2)
Mean of y’s
(3) Correlation
coefficient between x and y
Solution:

Calculation of Mean
\ Mean of x’s = 15.94 and Mean of y’s = 3.67

Calculation of ‘ r ’
x = 19.93  0.87 y
Therefore,
and y = 11.64  0.50 x
Therefore,
From (3) and (4)
r = ± 0.66
But regression coefficient are negative
r =  0.66

Index
6. 1 Introduction
6. 2 Correlation
6. 3 Types of Correlation
6. 4 Degrees of Correlation
6. 5 Methods of determining correlation
6. 6 Coefficients of Correlation for Bivariate
Grouped Data
6. 7 Probable Error
6. 8 Rank Correlation Coefficient
6. 9 Linear Regression
Chapter 7
