CMA Foundation · Fundamentals of Business Mathematics and Statistics · Correlation and Regression
Data on X and Y give: mean of X = 10, mean of Y = 20, and the regression coefficient of Y on X = 1.5. What is the regression equation of Y on X?
The regression equation is Y = 1.5X + 5. Using Y minus the mean of Y equals b times (X minus the mean of X), we get Y − 20 = 1.5(X − 10), which simplifies to Y = 1.5X + 5. The line passes through (10, 20).
- AY = 1.5X + 5Correct
- BY = 1.5X + 20
- CY = 1.5X − 5
- DY = 1.5X + 35
Explanation
The equation is Y − 20 = 1.5(X − 10). So Y = 1.5X − 15 + 20 = 1.5X + 5. Option 1.5X − 5 is a sign error in the constant.
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