Question

Consider the following problem involving linear correlation and linear regression:

How much should a healthy calf weigh? The following are taken from The Merck Veterinary Manual.  x is the age in weeks and y is the weight of a normal, healthy calf in kilograms.

x	1	3	10	16	26	36
y	42	50	75	100	150	200

   Which of the following would be the correct equation of the regression line?  enter a capital letter, no space, no period

        A.   y = - 4.5 x - 33.7         B.  y = 33.7 x - 4.5         C.  y= 33.7 x + 4.5         D.  y = 4.5 x + 33.7

   Which of the following is the linear correlation coefficient?  enter a capital letter, no space, no period

        A. - 0.998           B. - 0.995           C. 0.995           D. 0.998

   Which of the following is the coefficient of determination?  enter a capital letter, no space, no period

        A. - 0.998           B. - 0.995           C. 0.995           D. 0.998

   If a calf is x = 20 weeks old, normal, and healthy, how much should it weigh?  enter a capital letter, no space, no period

        A. 124 kg           B. 126 kg           C. 128 kg           D. 130 kg

Answer 1

Solution;-

=> option  D.  y = 4.5 x + 33.7

=> option D. 0.998

=> option C.0.995

Explanation = 0.9977^2 = 0.995

=> option A. 124

Explanation :     y = 4.5 x + 33.7 =   y = (4.5*20) + 33.7 = 123.7 = 124