What is the practice effect?

What is the practice effect?

• A. The potential change in performance due to familiarity with the task on repeated measurements.
• B. A measurement bias due to instrument calibration.
• C. The relation between sample size and effect size.
• D. The correlation between predictor and outcome.

Answer: (A)

Practice effect is the improvement (or change) in performance that happens simply because a person has done the task before. When a task is repeated, people often become more familiar with it, develop better strategies, or feel less anxious, which can boost scores even if their underlying ability hasn’t actually changed. That idea matches the description of a potential change in performance due to familiarity with the task on repeated measurements. The other options describe different ideas: instrument calibration bias refers to errors from the measuring tool itself, the relation between sample size and effect size concerns power and precision, and the correlation between predictor and outcome is about association between variables—none of these capture the familiarization effect seen with repeated testing.

Practice effect is the improvement (or change) in performance that happens simply because a person has done the task before. When a task is repeated, people often become more familiar with it, develop better strategies, or feel less anxious, which can boost scores even if their underlying ability hasn’t actually changed. That idea matches the description of a potential change in performance due to familiarity with the task on repeated measurements.

The other options describe different ideas: instrument calibration bias refers to errors from the measuring tool itself, the relation between sample size and effect size concerns power and precision, and the correlation between predictor and outcome is about association between variables—none of these capture the familiarization effect seen with repeated testing.