Summary for the course:
Test Construction PSMM-6 (2016)
Book: A conceptual introduction to psychometrics
by Mellenbergh
Chapter 1: Introduction
*TT= Test taker
1.2 Test definitions
Test: A psychological or educational test is an instrument for the measurement of a person´s
maximum or typical performance under standardized conditions, where the performance is
assumed to reflect one or more latent attributions.
àthis definitions has a number of elements
1. maximum performance test: asks the person to do his best to solve one or more problems
(answer in correctness – correct, partly correct, incorrect)
-ask the test takers to do the best they can to perform a task (abilities,
knowledge, skills)
2. typical performance test: asks the person to respond to one or more tasks, where the
responses are typical for the person. (answers not in correctness, but typify the person: ex:
personality of attitude tests
3. performances are measured under standardized conditions: test instructions, test
materials, administration procedure are fixed for different test takers
-> reason: must be comparable betw. Persons and occasions (Anlässe)
Latent attributes – latent variables – are not observable
Tests – surveys
- Survey cannot reflect latent attributes
- Surveys: to form a measurement index (ex. index of stress…)
Subtest: independent part of a test
Item: smallest possible subtest of a test
Dimensionality: The dimensionality of a test/subtest is equal to the number of latent attributes
(variables) which effects test performance.
è A test predominantly measures one latent attribute: unidimensional test