G Theory (Generalizability Theory)

G Theory, or Generalizability Theory, is a statistical framework used to assess the reliability of measurements or assessments across different conditions. It identifies how much of the variability in scores comes from true differences among subjects versus measurement factors like raters, tests, or time. By analyzing these sources of error, G Theory helps determine the consistency and dependability of results, ensuring that assessments accurately reflect what they intend to measure. It provides a comprehensive approach to evaluating measurement precision in various settings, such as education, psychology, and research.