In psychometrics and test theory, a true score is the hypothetical, error-free measurement of a person’s ability or trait. It represents the score that would be obtained if a test could be administered without any measurement error.
Key points about true scores:
- They are theoretical and cannot be directly observed
- Observed scores are composed of the true score plus measurement error
- The concept is fundamental to reliability theory in testing
True scores are used in calculating reliability coefficients and in interpreting test results. Understanding the relationship between true scores and observed scores helps in assessing the accuracy and consistency of measurement instruments in psychology, education, and other fields.
