Question

Cardiorespiratory fitness is widely recognized as a major component of overall physical well-being. Direct measurement of maximal oxygen uptake (VO2max) is the single best measure of such fitness, but direct measurement is time-consuming and expensive. It is therefore desirable to have a prediction equation for VO2max in terms of easily obtained quantities. A sample is taken and variables measured are age (years), time necessary to walk 1 mile (mins), and heart rate at the end of the walk (bpm) in addition to the VO2 max uptake. The following output is from a multiple regression. Based on the F-test alone, what is the correct conclusion about the regression slopes?

Predictor Constant age HR time Coef 19.222 0.006 -0.029 -1.504 Stdev 22.22 0.221 0.185 0.512 t-ratio 0.87 0.02 -0.16 -2.94 0.4055 0.9805 0.8774 0.01348 R-sq 44.03% R-sq (adj ) 28 . 76% s7.481 = Analysis of Variance SOURCE Regression Error Total DE MS 161.43 55.97 0.084 3 484.28 615.64 1099.93 2.88

Question options:

	1) All the regression slopes are equal to zero.
	2) We do not have the dataset, therefore, we are unable to make a conclusion about the slopes.
	3) We did not find significant evidence to conclude that at least one slope differs from zero.
	4) All the regression slopes do not equal zero.
	5) At least one of the regression slopes does not equal zero.

Question (1 point)

Suppose that a researcher studying the weight of female college athletes wants to predict the weights based on height, measured in inches, the percentage of body fat of an athlete, and age. The researcher calculates the regression equation as (weight) = 3.903*(height) + 1.385*(percent body fat) - 1.123*(age) - 82.426. If a female athlete is 63 inches tall, has a 21 percentage of body fat, and is 22 years old, what is her expected weight?

Question options:

	1) 332.694
	2) 250.268
	3) 62.086
	4) We do not know the observations in the data set, so we cannot answer that question.
	5) 167.842

Answer 1

Answer - 1: Based on F value, the decision is:

We did not find significant evidence to conclude that at least one slope differs from zero.

Option 3 is correct.

Answer - 2: Expected weight = 3.903*63 + 1.385*21 - 1.123*22 - 82.426 = 167.842

Option E is correct.