# AP Statistics : Census And Studies

## Example Questions

### Example Question #1 : How To Conduct An Observational Study

You are conducting the following series of observational studies to determine if generally understood parameters about a local population are accurate:

A. You stand on the sidewalk next to a stop sign to observe and record the number of cyclists and drivers who stop or don't stop.

B. You inform customers at a local fast food restaurant of your study to determine the proportion of healthy food choices from the menu and then observe their choices.

C. From your car in the mall parking lot, you observe the proportion of shoppers who hold the door open for the next person who enters or exits the mall.

D. To estimate the proportion of males and females in the local community, you observe spectators at a hockey match and count and record the gender in a randomly selected area of the crowd.

E. You review the daily sign-in sheets at a local fitness center to estimate the average number of workouts per week for residents of the local community.

Which observational study should yield the most accurate results?

Study D

Study B

Study E

Study A

Study C

Study C

Explanation:

Study C takes a representative sample of local residents, and it does so without affecting the outcomes.

Studies A and B are influenced by the person conducting the survey. Studies D and E are biased samples of the population.

Therefore, C should yield the most accurate results.

### Example Question #1 : How To Conduct An Observational Study

What situation would most warrant the method of observational study to produce accurate results?

Studying the social interactions between groups of baboons.

None of the above.

Studying the relationship between sleep deprivation and cold susceptibility.

Testing the effectiveness of a new drug.

Observing how chocolate consumption affects mood.

Studying the social interactions between groups of baboons.

Explanation:

Obseverational study does not involve any interference with the group being studied, so watching baboons in their natural habit would be best suited for this method.

### Example Question #41 : Data Collection

Kate would like to determine what flavors of ice cream are most popular among students in her AP Statistics class. In total, there are 100 students in the class. Which of the following would be an appropriate sampling methodology?

Obtain a census of the class and survey each person in the class to determine their favorite flavor of ice cream

There is no effective way to obtain a representative sample from the target population

Ask every fifth person that walks through the door what their favorite flavor of ice cream is before class starts

Group students into several homogeneous groups and choose one group to survey in order to determine the class's favorite ice cream flavor

Randomly select several of the most popular students in the class to answer questions about their favorite ice cream flavor

Obtain a census of the class and survey each person in the class to determine their favorite flavor of ice cream

Explanation:

In this situation, it is best to conduct a census in order to determine what the class's favorite flavor of ice cream is. Since there are only 100 students in the class, a sample of the class would be very small and may not be representative of the class as a whole.

### Example Question #1 : Census And Studies

Census is to __________ as survey is to __________.

population; group

population; sample

sample; population

cluster; stratum

There are no similarities between these two.