An employee at an animal hospital is keeping track of all of the dogs that are currently in-house and whether they have received their shots. She decides to record all dogs with brown hair first. Identify the type of sample described.

Options:

self selected

systematic

stratified

cluster

convenience

Stratified

Explanation:

In stratified sampling, a population is divided into subgroups or strata, based on peculiar characteristics or attributes that is shared by all members put into that strata. In other words, members in a strata are placed together based on specific and distinctive attributes that defer from other members of another strata.

In the case of the employee working at an animal hospital, the sample described in the question that she uses can be said to be stratified, as dogs with brown hair are placed in a strata.