Which is an independent variable in a study where Tractor Supply, a retailer of garden
and farming equipment, increases the price of its most popular lawn tractor by $5 every
month for three months and sees its effect on market share in the Dallas metropolitan
area?
a. The variable being manipulated by the researcher to cause the change.
b. $5 increase in retail price every month for three months.
c. The variable affected by the change.
d. Both a and b are correct.
e. Changes on market share after 3 months.
Which of the following statements concerning confidence intervals is FALSE?
a. A confidence interval can be inferred when a probabilistic sample is drawn.
b. A confidence interval is produced by calculating the degree of nonsampling error for
the particular statistic.
c. Precision can be increased by increasing sample size or decreasing the confidence
level.
d. A narrower confidence interval can be obtained by increasing the sample size.
e. A narrower confidence interval can be obtained by decreasing the degree of
confidence desired.