The authors of the paper Weight-Bearing Activity during Youth Is a More Important Factor for Peak Bone

The authors of the paper €œWeight-Bearing Activity during Youth Is a More Important Factor for Peak Bone Mass than Calcium Intake€ (Journal of Bone and Mineral Research [1994], 1089€“1096) studied a number of variables they thought might be related to bone mineral density (BMD). The accompanying data on x = weight at age 13 and y = bone mineral density at age 27 are consistent with summary quantities for women given in the paper.

A simple linear regression model was used to describe the relationship between weight at age 13 and BMD at age 27. For this data:

a. What percentage of observed variation in BMD at age 27 can be explained by the simple linear regression model?
b. Give a point estimate of s and interpret this estimate.
c. Give an estimate of the average change in BMD associated with a 1 kg increase in weight at age
13.
d. Compute a point estimate of the mean BMD at age 27 for women whose age 13 weight was 60 kg.

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2652187240 912 4 0 4 0 2 3 0 9 2 1 1 2 0 56 ( 43 607887787 7153 h-4. 9 4 2 3 0 6 6 4 1 9 4 2 88 557, 6 7 7 6 6 6 7 6 6 6 65 a0.558 SSTo 0.356 SSResid 0.313 b0.009