Bivariate Correlation

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Bivariate Correlation A Measure of Relationship
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Bivariate Correlation A Measure of Relationship
The correlation coefficient (r) is an index that
describes the extent to which two sets of
data are related it is a measure of the
relationship between two variables and ranges in
values between -1.00 and 1.00, inclusive.
The sign indicates the direction of the
relationship, where a plus () indicates a
positive relationship, and a negative (-)
indicates a negative relationship. The absolute
value of the coefficient indicates the magnitude
of the relationship.
A perfect positive (direct) correlation
coefficient is 1.00. A positive relationship
indicates that as one score goes up, the
other score goes up or as one score goes
down, the other score goes down. That is, the
value on one variable follows the value on the
other. A perfect negative (inverse) correlation
coefficient is -1.00. A negative relationship
indicates that as one score goes up, the other
score goes down. When there is no relationship
between two variables the correlation
coefficient is 0.00 (zero). All other possible
values (i.e., excluding 1.00, -1.00, and
0.00) are considered imperfect relationships
(both positive and negative).
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Bivariate Correlation A Measure of Relationship
Upper Diagonal (UD)
Highest/Strongest
Lowest/Weakest
Lower Diagonal (LD)
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Coefficient of Determination (r squared r2)
r 0.50 r2 0.25
The proportion of the total variance in Y that
can be associated with the variance in X.
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