Skip to content
Marlow Works

AP Psychology / Cognition

Lesson

Research design

Experiments, correlation, ethics, and measurement.

Explanation

An experiment manipulates an independent variable and measures a dependent variable. An operational definition states exactly how a variable is measured. Ethics rules protect participants; they are part of the science, not an extra afterthought.

Practice

Original Marlow Works items. Check the answer explanation after you try.

1 of 1Cognition · easy · short answer

In one or two sentences, distinguish encoding from retrieval in memory.

Original Marlow Works item — not a College Board question.

Take your time—this is practice, not a test.

Previous lessonNext lesson

Related resources

External links with reuse status. Marlow Works is independent and does not copy restricted exam or textbook material.

  • Official / link only

    AP Psychology course page

    Official five-unit framework and science practices.

    College Board · All rights reserved · accessed 2026-10-01

    Open source

  • Reference only — do not copy

    OpenStax Psychology 2e

    Useful psychology background, but current publisher terms restrict commercial reuse and AI ingestion.

    OpenStax · CC BY-NC-SA 4.0 with additional restrictions · accessed 2026-10-01

    Link only. Do not republish or ingest this book.

    Open source