Psychometric Properties of the JCTI, IAW, GIE, and JCCES Tests: Reliability and Validity Analysis

1) Reliability and Internal Consistency

Reliability is a primary indicator of a test’s ability to deliver consistent and stable results. This section discusses the internal consistency of each test using Cronbach’s Alpha as the key measure.

JCTI (Jouve-Cerebrals Test of Induction): The JCTI exhibits a strong internal consistency with a Cronbach’s Alpha over 0.90, indicating cohesive item measurements for inductive reasoning. The test’s use of the 3-Parameter Logistic Model from Item Response Theory (IRT) further supports its capacity to measure diverse levels of inductive reasoning accurately.

IAW (I Am a Word Test): As an open-ended assessment of verbal IQ, the IAW test achieves a Cronbach’s Alpha of 0.94, demonstrating its strong reliability. It uses a 2-Parameter Logistic Model to confirm effective measurement of vocabulary and reasoning abilities across different proficiency levels.

GIE (General Information Evaluation): With an internal consistency of 0.91 for its 30-item short form, the GIE provides consistent assessment across its items. This reliability reflects the test's ability to accurately gauge general knowledge.

JCCES (Jouve-Cerebrals Crystallized Educational Scale): Scoring an overall Cronbach’s Alpha of 0.96, the JCCES demonstrates high reliability. The subtests also score well, ranging from 0.87 to 0.94, further supporting its ability to accurately measure different dimensions of crystallized intelligence.

2) Validity Evidence

Validity assessments are essential to determine how well each test measures its intended cognitive skills. This section covers validity evidence across concurrent, criterion, and construct measures.

JCTI: Demonstrating concurrent validity, the JCTI shows high correlation (r = .87) with Raven's Advanced Progressive Matrices, solidifying its accuracy in evaluating inductive reasoning abilities.

IAW: The IAW Test’s validity is supported by its strong correlation (r > .80) with verbal comprehension indices from established assessments, like the WAIS, confirming its relevance in assessing verbal skills.

GIE: The GIE short form’s criterion validity is evidenced by a significant correlation of 0.81 with the General Knowledge subtest of the JCCES, reinforcing its precision in measuring general knowledge.

JCCES: Through factor analysis and Multidimensional Scaling, the JCCES has demonstrated construct validity, aligning well with core cognitive abilities such as verbal and mathematical reasoning. High correlations (r > .80) with the WAIS Full-Scale IQ and standardized tests like the SAT and ASVAB AFQT support its accuracy in assessing crystallized intelligence.

3) Item Response Theory (IRT) Applications

The application of Item Response Theory (IRT) to these tests allows for more nuanced measurement of cognitive abilities. Each test’s IRT model provides insights into how effectively individual items assess varying ability levels.

JCTI: With the 3-Parameter Logistic Model, the JCTI effectively calibrates its items to differentiate among diverse inductive reasoning levels, providing a clear picture of the skill range it measures.

IAW and JCCES: Both the IAW and JCCES utilize the 2-Parameter Logistic Model, which confirms that their items measure participants’ verbal IQ and crystallized knowledge levels accurately. This application of IRT supports precise item-level assessment.