STATS PRACTICE QUIZ. D772 QUESTIONS &
ANSWERS GRADED A+|| LATEST UPDATE 2025/26
example of a population from a research study -CORRECTANSWER All American
women under the age of 60
A pollster selects seven random marketing firms and conducts in-person interviews
about industry trends for all employees at those firms. What is the sampling method
described in this situation? -CORRECTANSWER Cluster
Which group represents a placebo group? -CORRECTANSWER In a study on heart
medicine, those receiving a pill with no medical benefit
Which study is a double-blind experiment? -CORRECTANSWER Researchers studying
the effect of caffeine on attention span administer caffeine-filled pills and placebo pills to
participants randomly assigned to each group. The pills are coded so that neither the
patient nor the person administering the pill knows which kind it is.
Which implication follows from using a non-representative sample? -
CORRECTANSWER The sample produces data that is not similar to what would be
obtained from the entire population.
, Which example illustrates a potential convenience sampling bias? -
CORRECTANSWER An employer posts a survey on an employee intranet message
board that asks, but does not require, employees to provide their opinion on food
options in the company cafeteria.
A survey given to teenagers about their driving habits had a low return rate because
many young drivers did not want to CORRECTANSWER questions about this topic.
What is illustrated in this scenario? -CORRECTANSWER Non-response bias
A researcher planted two maple trees in plain soil and two maple trees in fertilized soil.
Each tree was given 20 mL of water and 8 hours of sunlight each day. After four weeks,
the trees in plain soil were 7% taller than the trees in fertilized soil.
Is this result likely to be statistically significant? -CORRECTANSWER No, because the
sample size for the study was too small.
A sociologist is designing a study that can be used to test a hypothesis. What should
the sociologist avoid doing to prevent results that are potentially misleading? -
CORRECTANSWER Duplicating data to increase the sample size
A company randomly chose 1,000 customers for an experiment. For half of the
customers, the company sent out regular marketing emails. For the other half, the
company sent physical fliers. At the conclusion of the study, it was found that the
ANSWERS GRADED A+|| LATEST UPDATE 2025/26
example of a population from a research study -CORRECTANSWER All American
women under the age of 60
A pollster selects seven random marketing firms and conducts in-person interviews
about industry trends for all employees at those firms. What is the sampling method
described in this situation? -CORRECTANSWER Cluster
Which group represents a placebo group? -CORRECTANSWER In a study on heart
medicine, those receiving a pill with no medical benefit
Which study is a double-blind experiment? -CORRECTANSWER Researchers studying
the effect of caffeine on attention span administer caffeine-filled pills and placebo pills to
participants randomly assigned to each group. The pills are coded so that neither the
patient nor the person administering the pill knows which kind it is.
Which implication follows from using a non-representative sample? -
CORRECTANSWER The sample produces data that is not similar to what would be
obtained from the entire population.
, Which example illustrates a potential convenience sampling bias? -
CORRECTANSWER An employer posts a survey on an employee intranet message
board that asks, but does not require, employees to provide their opinion on food
options in the company cafeteria.
A survey given to teenagers about their driving habits had a low return rate because
many young drivers did not want to CORRECTANSWER questions about this topic.
What is illustrated in this scenario? -CORRECTANSWER Non-response bias
A researcher planted two maple trees in plain soil and two maple trees in fertilized soil.
Each tree was given 20 mL of water and 8 hours of sunlight each day. After four weeks,
the trees in plain soil were 7% taller than the trees in fertilized soil.
Is this result likely to be statistically significant? -CORRECTANSWER No, because the
sample size for the study was too small.
A sociologist is designing a study that can be used to test a hypothesis. What should
the sociologist avoid doing to prevent results that are potentially misleading? -
CORRECTANSWER Duplicating data to increase the sample size
A company randomly chose 1,000 customers for an experiment. For half of the
customers, the company sent out regular marketing emails. For the other half, the
company sent physical fliers. At the conclusion of the study, it was found that the
