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Chapter 4: Q. 18 (page 238)

Parking on campus The director of student life at a university wants to estimate the proportion of undergraduate students who regularly park a car on campus. Describe how to select a stratified random sample of approximately 100students. Explain your choice of strata and why stratified random sampling might be preferred in this context.

Short Answer

Expert verified

Strata is Gender (male/ female) and SRS is preferred in this context because the proportion of undergraduates parking the car differs for males and females.

Step by step solution

01

Given information 

We need to find the strata and reason for the SRS preference in this context.

02

Explanation

Simple random samples are obtained from independent subgroups using stratified random sampling (stratum).

Because the proportion of undergraduate students who park their automobiles on campus on a regular basis may differ between males and girls, using gender as the stratum might be informative. Females, for example, maybe more likely than males to park a car on campus because more females in the school possess a car.

We would need to pick roughly 50male undergraduate students and approximately 50female undergraduate students for a stratified random sample of approximately 100students.

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