Concept 4

Identify the population to which results can be extended (SAT).

The population is the exact group the sample was drawn from.

Core Idea

The population you can generalize to is defined by where the sample was drawn from — pay close attention to the exact group described.

Understanding

Scope check: the population is the group the sample came from, not the broader group you wish you had.

If the question says the sample was randomly selected from public middle schools in Ohio, the results generalize to public middle school teachers in Ohio and no farther.

  • Too broad: "all teachers in Ohio"
  • Too narrow: "the 250 teachers who participated"
  • Wrong shift: "all public middle school teachers in the United States"

Step by Step

  1. Find the exact sentence describing how participants were selected.
  2. Identify the sampling frame — the specific group from which the sample was drawn.
  3. Match that group to the answer choice. The correct answer will mirror the sampling frame precisely.

Misconceptions

  • Generalizing to a broader group than the sampling frame allows.
  • Thinking that demographic similarity is enough for generalization.
  • Ignoring qualifiers like age range, geographic region, or membership status that narrow the population.
Question

Worked Example

Researchers randomly selected 250 teachers from public middle schools in Ohio to study job satisfaction. Which of the following populations can the results of this study be generalized to?

Select an answer to see the explanation