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AP Psychology · Unit 0 Quiz

AP Psychology Unit 0 Practice Test

Twelve original multiple-choice questions on research methods and science practices — variables, experimental design, sampling, ethics, and statistics — with instant scoring and an explanation for every answer. This is the material the AAQ free-response question lives on.

Ready to test yourself?

All 12 questions focus on Unit 0: Research Methods — shuffled every run.

Pick an answer to see instantly whether you're right and why, then move on. Your score comes at the end.

What These Unit 0 Questions Cover

The set mirrors how research methods actually show up on the exam: identifying the independent and dependent variable in a described study, spotting the third-variable problem behind a correlation, choosing the right operational definition, knowing why random assignment (not random sampling) is what permits causal claims, and reading simple statistics — when an outlier drags the mean away from the median, and what a small standard deviation means. Ethics questions cover informed consent, deception, and debriefing.

Shaky on any of these? The Unit 0 study guide walks through all five research methods with an interactive method-spotting game, and the AAQ guide shows how the same vocabulary earns free-response points.

Why Research Methods Are Worth Drilling First

There's no separately scored "Unit 0" on the exam — and that's exactly why it matters. Research-design questions are woven through the multiple-choice section of every content unit, and the Article Analysis Question asks you to dissect a real study's method, variables, ethics, and generalizability for a full third of one FRQ. Ten minutes of methods practice pays off across the whole test.

Unit 0 Practice Test — FAQ

Is Unit 0 a scored unit on the AP Psychology exam?

Not as a standalone section. "Unit 0" is the course's science-practices foundation, and the exam tests it everywhere: methods questions appear throughout the multiple choice, and the AAQ is entirely about analyzing a research study.

What should I know from Unit 0?

Variables and operational definitions, random assignment vs. random sampling, correlation vs. causation, double-blind controls, research ethics, and basic descriptive statistics. If you can label any described study with IV, DV, method, and flaw, you're ready.

All 12 Practice Questions with Answers

Prefer to review instead of quiz? Every question in this set is below — open one to reveal the answer and the reasoning. (The interactive version above shuffles both questions and answer positions, so reading this list first won't spoil a retake.)

1. In an experiment testing whether hours of sleep affect memory-test performance, the hours of sleep participants get is the:
  • Independent variable ✓
  • Dependent variable
  • Confounding variable
  • Operational definition

Why: The independent variable is what the researcher manipulates — here, hours of sleep. The memory score that gets measured is the dependent variable.

2. In that same sleep-and-memory experiment, the participants' scores on the memory test are the:
  • Control condition
  • Independent variable
  • Dependent variable ✓
  • Random sample

Why: The dependent variable is the outcome the researcher measures to see whether the manipulation had an effect.

3. The main purpose of random assignment is to:
  • Make sure the sample represents the population
  • Spread participant differences evenly across groups so causal conclusions are possible ✓
  • Keep participants from knowing which group they are in
  • Guarantee statistically significant results

Why: Random assignment equalizes groups on pre-existing differences, which is what lets experiments support cause-and-effect claims. Representing the population is the job of random sampling.

4. Ice cream sales and drowning deaths rise together each year. The best explanation is:
  • Ice cream causes drowning
  • Drowning reports increase ice cream sales
  • A third variable — summer heat — drives both ✓
  • The correlation must be a coincidence

Why: This is the classic third-variable problem: correlation between two variables can be produced by something else (hot weather) influencing both.

5. Defining 'aggression' as 'the number of times a child hits the doll during a 10-minute session' is an example of:
  • A hypothesis
  • An operational definition ✓
  • A theory
  • Debriefing

Why: An operational definition specifies exactly how a variable will be measured or produced, so the study can be replicated.

6. In a double-blind study, who is unaware of which participants received the real treatment?
  • Only the participants
  • Only the researchers who interact with participants
  • Both the participants and those researchers ✓
  • Neither — that describes a single-blind study

Why: Double-blind procedures keep both sides unaware, controlling for placebo effects and experimenter bias at the same time.

7. A researcher studies one patient with a rare brain injury in extreme depth. The main limitation of this case study is:
  • It cannot describe behavior in detail
  • Its findings may not generalize to other people ✓
  • It is unethical by definition
  • It cannot generate hypotheses

Why: Case studies give rich detail about a single person, but a single unusual case may not represent anyone else — generalizability is the core weakness.

8. Watching how shoppers behave in a real grocery store without interfering is an example of:
  • Naturalistic observation ✓
  • A laboratory experiment
  • A structured survey
  • Random assignment

Why: Naturalistic observation records behavior in its real-world setting without manipulation — high realism, but no control over variables.

9. To be able to generalize survey results to all students at a school, a researcher should use:
  • A convenience sample
  • A random sample of the school's students ✓
  • Only volunteers
  • The largest possible sample of one classroom

Why: A random sample gives every member of the population an equal chance of selection, which is what makes generalization defensible.

10. If a study involves deception, researchers are ethically required to:
  • Pay participants extra
  • Debrief participants afterward, explaining the true purpose ✓
  • Keep the deception secret permanently
  • Skip informed consent entirely

Why: Deception can be permitted when justified, but participants must be debriefed afterward — told what really happened and why.

11. In a neighborhood where most families earn about $60,000, one billionaire moves in. Which statistic is pulled up the most?
  • The median income
  • The mode of incomes
  • The mean income ✓
  • The standard deviation stays the same

Why: The mean is sensitive to extreme scores, so one outlier drags it upward; the median barely moves, which is why skewed data are better described by the median.

12. A small standard deviation tells you that scores in a data set are:
  • Clustered closely around the mean ✓
  • Spread far from the mean
  • Impossible to compare
  • Always normally distributed

Why: Standard deviation measures spread: small means scores hug the mean, large means they scatter widely.

Keep Going

Mix all five units in one shuffled test, or study the methods first.

Take the Full Practice Test

Original questions written for the redesigned AP Psychology course; not reproduced from any official exam. AppsychologyLab is not affiliated with the College Board.

Written and fact-checked by the AppsychologyLab Editorial Team against College Board materials. Last reviewed 2026-08-26. How we verify.