Question

An auto analyst is conducting a satisfaction survey, sampling from a list of 10,000 new car buyers. The list includes 2500 Ford buyers, 2500 GM buyers, 2500 Honda buyers, and 2500 Toyota buyers. The analyst selects a sample of 400 car buyers by randomly sampling 100 buyers of each brand. What sampling method is used?

Answer 1

Answer: Stratified random sampling.

Explanation:

In a simple random sampling, every one has an equal chance of being chosen. This case is quite different.

In this case, since the analyst selects a sample of 400 car buyers by randomly sampling 100 buyers of each brand, this is a stratified random sampling since the outcome was already divided into 100 cars for each brand.