Consider the following information about variable X: Mean = 4, standard deviation = 2.
Consider the following information about variable Y: Mean = 5, standard deviation = 3.
If there is a correlation of r = 0.52 between variable X and variable Y, what is the intercept for a simple linear regression equation predicting Y on the basis of X? Please provide your answer as a raw score (not a z score) with a minimum of two decimal places.
Solution:
Given:
variable X: Mean = 4, standard deviation = 2
, sx = 2
variable Y: Mean =5, standard deviation = 3
, sy = 3
a correlation of r = 0.52 between variable X and variable Y.
We have to find the intercept for a simple linear regression equation predicting Y on the basis of X.

where



Thus




Thus the intercept for a simple linear regression equation predicting Y on the basis of X is: b0 = 1.88
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