Question

dr. roberts wants to select a sample of 10 students from his physics course to work on a special research project. to select the sample, dr. roberts refers to an alphabetized list of all enrolled students and selects every 15th student on the list until 10 students are chosen. which of the following best describes the sampling method used by dr. roberts?
this is stratified random sampling because the list is ordered and students are selected from different parts of the alphabet.
this is systematic sampling because students are selected at regular intervals from an ordered list.
this is methodical sampling because dr. roberts followed a fixed pattern.
this is simple random sampling because each student has an equal chance of being selected.
this is cluster sampling because dr. roberts is selecting students from a single list.

Explanation:

Systematic sampling involves selecting elements at fixed intervals from an ordered list. Here, every 15th student is chosen.

Answer:

This is systematic sampling because students are selected at regular intervals from an ordered list.