Manufacturers were subdivided into groups by volume of sales. Those with more than $100 million in sales were classified as large; those from $50 to $100 million as medium size; and those between $25 and $50 million..., and so on. Samples were then selected from each of these groups. What is this type of sampling called?
A) Simple random
B) Stratified random
C) Cluster
D) Systematic

Question

Quizplus · Accepted Answer

This is stratified random sampling, as the population (manufacturers) was first divided into strata (by volume of sales) and then samples were selected from each stratum.

Manufacturers Were Subdivided into Groups by Volume of Sales