This essay on Psychometrics consists of these four sections: Psychological Measurement, Fundamental Measurement Concepts, Formal Measurement Models, and Interpreting Scores on Tests and Inventories. This essay discusses the following subjects: psychological scaling, measurement and measurement scales, purposes and uses of tests and inventories, item types and test formats, reliability, generalizability, validity, true score theory, estimating true score, a model for error, item response theory, estimating proficiency, estimating item parameters, notation and general principles, norm-reference and criterion-referenced approaches in test development, understanding and interpreting test scores, percentile and standard score bands, setting standards on norm- and criterion-referenced tests, computer-based testing, and performance assessment.
