MAT 131 Unit #2 Exam
Score - ANS-100/100
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. The particular interest was whether higher income would cause
shoppers to spend more on groceries. A random sample of shoppers at a local supermarket
was obtained. A questionnaire was administered asking about the weekly income of each
shopper's family and their grocery bill for that week. The gender of each shopper was also
obtained. The relationship between grocery expenditure and income was assessed by
calculating both a correlation for the females only and a correlation for the males only. For the
females, r = 0.45 and for the males, r = 0.38. We conclude that: - ANS-the relationship between
grocery expenditures and income is stronger for females.
What can be said of the correlation between the brand of an automobile and its quality? -
ANS-Correlation makes no sense here, because brand is a categorical variable.
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. The particular interest was whether higher income would result in
shoppers spending more on groceries. A random sample of shoppers at a local supermarket
was obtained, and a questionnaire was administered asking about the weekly income of the
shopper's family and the grocery bill for that week. The gender of the shopper was also
obtained. The correlation was found to be r = 0.8056. The amount of variation in the response
explained by the regression line is: - ANS-64.9%
The volume of oxygen consumed (in liters per minute) while a person is at rest and while a
person is exercising (running on a treadmill) were both measured for 50 subjects. The goal is to
determine if the volume of oxygen consumed during aerobic exercise can be estimated from the
amount consumed at rest. The results are plotted below. The scatterplot suggests that there is: -
ANS-both a positive association between volume of oxygen consumed at rest and while
running, and an outlier in the plot.
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. Of particular interest was whether higher income would result in
shoppers spending more on groceries. A random sample of shoppers at a local supermarket
was obtained. A questionnaire was administered asking about the weekly income of each
shopper's family and their grocery bill for that week. The explanatory variable is: - ANS-weekly
income
Frequent food questionnaires (FFQ) are a simple way to obtain information on the foods
individuals consume by asking them questions about typical amounts of food consumed in a
day, a week, or a month. A more accurate picture is obtained by obtaining a detailed food diary
Score - ANS-100/100
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. The particular interest was whether higher income would cause
shoppers to spend more on groceries. A random sample of shoppers at a local supermarket
was obtained. A questionnaire was administered asking about the weekly income of each
shopper's family and their grocery bill for that week. The gender of each shopper was also
obtained. The relationship between grocery expenditure and income was assessed by
calculating both a correlation for the females only and a correlation for the males only. For the
females, r = 0.45 and for the males, r = 0.38. We conclude that: - ANS-the relationship between
grocery expenditures and income is stronger for females.
What can be said of the correlation between the brand of an automobile and its quality? -
ANS-Correlation makes no sense here, because brand is a categorical variable.
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. The particular interest was whether higher income would result in
shoppers spending more on groceries. A random sample of shoppers at a local supermarket
was obtained, and a questionnaire was administered asking about the weekly income of the
shopper's family and the grocery bill for that week. The gender of the shopper was also
obtained. The correlation was found to be r = 0.8056. The amount of variation in the response
explained by the regression line is: - ANS-64.9%
The volume of oxygen consumed (in liters per minute) while a person is at rest and while a
person is exercising (running on a treadmill) were both measured for 50 subjects. The goal is to
determine if the volume of oxygen consumed during aerobic exercise can be estimated from the
amount consumed at rest. The results are plotted below. The scatterplot suggests that there is: -
ANS-both a positive association between volume of oxygen consumed at rest and while
running, and an outlier in the plot.
An economist conducted a study of the possible association between weekly income and
weekly grocery expenditures. Of particular interest was whether higher income would result in
shoppers spending more on groceries. A random sample of shoppers at a local supermarket
was obtained. A questionnaire was administered asking about the weekly income of each
shopper's family and their grocery bill for that week. The explanatory variable is: - ANS-weekly
income
Frequent food questionnaires (FFQ) are a simple way to obtain information on the foods
individuals consume by asking them questions about typical amounts of food consumed in a
day, a week, or a month. A more accurate picture is obtained by obtaining a detailed food diary
