Q. A survey of 1000 adults ages 30 to 35 is conducted. The number of years of schooling and the annual salary for each person in the survey is recorded. The correlation between years of schooling and annual salary is found to be 0.27. Suppose instead the average salary of all individuals in the survey with the same number of years of schooling was calculated and the correlation between these averages and years of schooling was computed. This correlation would most likely be

A.equal to 0.27. B.larger than 0.27. C.less than 0.27.

Q. The regression line to predict average exam grade from hours of study is y = 15 + 5.6*x. The slope of the regression line indicates

A.for any student, an extra hour of study increases the grade 5.6 points.

B.on average, an extra hour of study will increase the grade 5.6 points.

C.an extra hour of study will increase the grade 15 points.

Q. At a large department store, the amount a shopper spent and the shopper's gender (male or female) were recorded. To determine if gender is useful in explaining the amount of money a shopper spends at the store we could

A.make side-by-side boxplots of the distribution of the amount spent by males and the distribution of the amount spent by females.

B.compute the correlation between the amount spent and gender.

C.compute the least-squares regression line of amount spent on gender.