AP Stats Sampling Methods and Design 3

Question 1

A study finds that students who eat breakfast score higher on exams. A lurking variable that could explain this relationship is:

Accepted Answer

Socioeconomic status of the family

Answer

Socioeconomic status affects both the ability to regularly eat breakfast and access to educational resources that improve exam scores.

Question 2

The difference between an observational study and an experiment is that in an experiment:

Accepted Answer

The researcher actively imposes treatments on subjects

Answer

In an experiment, the researcher deliberately assigns treatments to subjects, whereas an observational study merely records existing conditions.

Question 3

A survey asks: 'Do you agree that the government wastes taxpayer money?' This question suffers from:

Accepted Answer

Leading question bias

Answer

The wording 'Do you agree that' steers respondents toward agreement, introducing leading question bias that inflates 'yes' responses.

Question 4

In a completely randomized design, the purpose of random assignment is to:

Accepted Answer

Balance confounding variables across treatment groups on average

Answer

Random assignment distributes both known and unknown confounding variables roughly equally among groups, allowing causal conclusions.

Question 5

A researcher surveys shoppers leaving a grocery store on a Tuesday morning. This is an example of:

Accepted Answer

Convenience sampling

Answer

Selecting whoever is easily available (shoppers present at that specific time and place) is convenience sampling, which is prone to undercoverage bias.

AP Practice Test

AP Practice Test

AP Stats Sampling Methods and Design 3