Chapter 4.1, Problem 38E

To determine

To choose correct option.

Answer to Problem 38E

d) A stratified random sample.

Explanation of Solution

First need to know about sampling methods:

Simple random sampling: It uses a sample size n in which every sample of size n has an equal chance of being selected.

Stratified sampling: It draws simple random samples from independent subgroups.

Systematic sampling: It is letting every kth individual be in the sample.

Cluster sampling: It divides the population into non-overlapping subgroups and some of these subgroups are then in the sample.

Convenience sampling: It uses a subgroup from the population, that is conveniently chosen.

This study used stratified sampling method. Because, they choose separate random samples of plots from floodplain, coast, foothills, and high hills which are the different stratum.