Wiki Page, Math 13 - Perez Sandbox : Conclusions Permitted by Different Study Designs

Wiki Page
2026-01-17T21:14:54-08:00

If individuals are selected from the population by random selection, then we can make an inference about the population(s) and draw conclusions about the population(s).

If individuals are assigned to groups by random assignment, then we can make an inference about a treatment and draw cause-and-effect conclusions.

Examples of Different Study Designs

Individuals are randomly selected from the population and randomly assigned to groups example: Select a random sample from one population. Randomly assign individuals in the sample to different treatment groups.

Individuals are randomly selected from the population and not randomly assigned to groups example: Select random samples from existing distinct populations.

Individuals are not randomly selected from the population and randomly assigned to groups example: Find a group of individuals. Randomly assign individuals to treatment groups.

Individuals are not randomly selected from the population and not randomly assigned to groups example: Examine available individuals from distinct groups.