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In two regression lines, if byx = 0.9 and bxy = 0.4, the angle between them is
AAcute
BObtuse
CRight angle
DCannot be determined
Answer & Solution
Correct answer: A. Acute
1. Slope of y on x = byx = 0.9; slope of x on y as a y-vs-x line is 1/bxy = 2.5.
2. Both slopes positive and different, so lines intersect at an acute angle.
3. Right angle would require r = 0; r = sqrt(0.36) = 0.6 here so not right.
4. So the angle between them is acute.
_Source: ICAI BoS Foundation Paper 3, Ch 17 'Regression', p.13_
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