Energy-drink advertising consistently emphasizes a physically active lifestyle and often features extreme sports and risk taking. Are these typical characteristics of an energy-drink consumer? A researcher decided to examine the links between energy-drink consumption, sport-related (jock) identity, and risk taking. ⁵ She invited over 1500 undergraduate students enrolled in large introductory-level courses at a public university to participate. Each participant had to complete a 45-minute anonymous questionnaire. From this questionnaire jock identity and risk-taking scores were obtained, where the higher the score, the stronger the trait. She ended up with 795 respondents. The following table summarizes the results of a multiple regression analysis using the frequency of energy-drink consumption in the past 30 days as the response variable:

Explanatory variable	b
Age	−0.02
Sex (1 = female, 0 = male)	−0.11 **
Race (1 = nonwhite, 0 = white)	−0.02
Ethnicity (1 = Hispanic, 0 = non-Hispanic)	0.10 **
Parental education	0.02
College GPA	−0.01
Jock identity	0.05
Risk taking	0.19 ***

A superscript of ^** means that the individual coefficient t test had a P -value less than 0.01, and a superscript of ^*** means that the test had a P -value less than 0.001. All other P -values were greater than 0.05.

(a) The overall F statistic is reported to be 8.11. What are the degrees of freedom associated with this statistic?

(b) R ² is reported to be 0.28. What percent of the variation in energy-drink consumption is explained by the model? Is this a highly predictive model? Explain.

(c) Interpret each of the regression coefficients that are significant.

Answer rating: 100% (QA)

a The degrees of freedom of this statistics are 7 787 b 28 percent of ... View the full answer