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Question
If the correlation coefficient of two sets of variables (X, Y) is `(-3)/4`, which one of the following statements is true for the same set of variables?
Options
Only one of the two regression lines has a negative coefficient.
Both regression coefficients are positive.
Both regression coefficients are negative.
One of the lines of regression is parallel to the x-axis.
Solution
Both regression coefficients are negative.
Explanation:
A negative correlation occurs when the correlation coefficient is smaller than O. Thus if both regressions are negative, the correlation coefficient will likewise be negative. As a result, if the correlation coefficient is negative, both regression coefficients will be negative.
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