Reliability as Projection in Operator-Theoretic Test Theory: Conditional Expectation, Hilbert Space Geometry, and Implications for Psychometric Practice

Publication: Educational and Psychological Measurement
UBC Author(s): Bruno Zumbo (Educational & Counselling Psychology & Special Education / Faculty of Education)
ISSN: 00131644
Volume: 86
Page Range: 433-469
Publication Date: June 2026