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If r = -0.7 and sigma_y = 10, sigma_x = 5, then byx equals
Aminus two point zero
Bminus zero point seven
Cnegative one point four
Dminus one point zero
Answer & Solution
Correct answer: C. negative one point four
1. byx = r * (sigma_y / sigma_x).
2. Substitute r = -0.7, sigma_y = 10, sigma_x = 5.
3. byx = -0.7 * (10/5) = -0.7 * 2.
4. byx = -1.4, written as 'negative one point four'.
_Source: ICAI BoS Foundation Paper 3, Ch 17 'Regression', p.11_
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