The scatterplot shows the lean body mass and metabolic rate for a sample of = adults. For each person, the lean body mass is the subject’s total weight in kilograms less any weight due to fat. The metabolic rate is the number of calories burned in a 24-hour period.

Because a person with no lean body mass should burn no calories, it makes sense to model the relationship with a direct variation function in the form y = kx. Models were tried using different values of k (k = 25, k = 26, etc.) and the sum of squared residuals (SSR) was calculated for each value of k. Here is a scatterplot showing the relationship between SSR and k:

According to the scatterplot, what is the ideal value of k to use for predicting metabolic rate?

a. 24

b. 25

c. 29

d. 31

e. 36

Short Answer

Expert verified

The correct option is (d).

Step by step solution

01

Given information

02

Explanation

The SSR is smallest when k=31 as shown in the scatterplot illustrating the relationship between SSR and k because the lowest point in the scatterplot corresponds to k=31 Because k=31 is the least squares direct variation regression line between x and y, it minimizes the sum of the squares residuals, we should utilize it to make predictions when applying the model.

Thus, option (d) is the correct option.

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Most popular questions from this chapter

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