Xavier Jouve, Ph.D., is a psychometrician specializing in cognitive-ability measurement, item response theory, and test construction. As Head of Research at Cogn-IQ, he has built the Jouve-Cerebrals series of fluid- and crystallized-ability tests (JCTI, JCCES, JCWS, JCFS), calibrated with 2PL IRT and computerized adaptive testing. His original methodological work includes group-theoretic symmetry constraints and self-calibrating estimators for item response models, a randomized resampling approach to reliability (the coefficient ξ), Bayesian hierarchical estimation, and scoring methods for open-ended ability items. His Épreuve de Performance Cognitive (2005) was published in France by ECPA (Pearson).
Xavier Jouve, Ph.D.
Psychometrician
Articles (76)
- Effect Size vs. P-Value Explained
- What Is Mensa? Membership and Testing
- IQ Test Anxiety: How Stress Affects Your Score
- Raven’s Progressive Matrices: Culture-Fair IQ Test
- The IQ Bell Curve: How Scores Are Distributed
- How to Interpret IQ Test Results
- Computerized Adaptive Testing Explained
- Autism and IQ: Intelligence in ASD
- Average IQ by Age Across the Lifespan
- Does Bilingualism Make You Smarter?
- ADHD and Intelligence: The IQ-Attention Link
- How to Test Your Child’s IQ
- Sex Differences in Cognitive Abilities: What the Data Show
- Item Response Theory: How Modern Tests Work
- IQ of 130, 140, or 150: Rarity and Real-World Meaning
- Do IQ Tests Measure What They Claim?
- WAIS-IV vs WAIS-V: What Changed and Why It Matters
- Fluid vs. Crystallized Intelligence
- IQ vs. EQ: Which Matters More?
- The Flynn Effect: Are Humans Getting Smarter?
- Online IQ Tests vs Professional Assessments: How Accurate?
- Psychometrics: The Science of Psychological Measurement
- SAT Scores and IQ: How Closely Are They Correlated?
- Can You Actually Increase Your IQ?
- High IQ Ranges: Percentiles and Meaning
- Bridging Psychology and Psychometrics
- Differential Item Functioning and Response Process
- Integrating SDT and IRT Models for Mixed-Format Exams
- Rotation Local Solutions in Multidimensional IRT
- Group-Theoretic Symmetries in Item Response Theory
- Bayesian Hierarchical 2PLM with ADVI
- Tellegen-Briggs Formula 4 for Composite Scores
- Simulated IRT Datasets for Psychometric Research
- Cognitive Ability and Decision-Making Biases
- The Neuroscience of High Intelligence
- History of the WAIS: Wechsler-Bellevue to WAIS-V
- Overclaiming: Why People Claim Knowledge They Don’t Have
- Sequential GLR Tests for Item Monitoring
- Computerized Adaptive Testing Techniques
- JCTI Validity and Reliability: The Evidence
- JCCES: Reliability of the Crystallized Skills Scale
- JCFS: Assessing Nonverbal Intelligence
- JCWS: A Verbal Abilities Test
- IAW: Assessing Verbal Intelligence
- Flynn Effect Trends: The Rise, Stall, and Reversal of IQ
- NIH Toolbox: Cognitive Change in Intellectual Disability
- Coefficient Alpha and Alternatives in Non-Normal Data
- Cognitive Ability and Top Earners
- Validity of WISC-V Strengths and Weaknesses Profiles
- Attenuation-Corrected Reliability Estimators
- Continuous Norming for Cognitive Tests
- Resistance to Online Misinformation
- NCS-6: A Brief Need for Cognition Scale
- Bayesian SEM Prior Sensitivity
- Nonmemory-Based Performance Validity Tests
- Item Distributions and Cronbach’s Alpha
- Factor Retention in Exploratory Factor Analysis
- WISC-V Short-Form IQ Estimation
- Rasch vs Classical Equating in Small Samples
- Estimation Methods and SEM Fit Indices
- Intelligence and Music Aptitude in Piano Learning
- Spatial vs. Abstract Reasoning: One Factor or Two?
- JCCES and GAMA: Multidimensional Scaling Analysis
- JCCES and GAMA: Cognitive Factor Analysis
- JCCES and ACT: A Factor Analysis
- WAIS-IV CHC Factor Structure in Older Adults
- Item Parameter Estimation for GGUM
- Dimensional Structure of JCCES Math Items
- SAT Scores and General Cognitive Ability
- Cognitive Measures of Reasoning and Language
- Stanford-Binet vs WAIS in Intellectual Disability
- What the WAIS-IV Measures: Subtests Explained
- JCCES Crystallized Index and Cognitive and Academic Measures
- JCCES and RIAS Verbal Scale: PCA Analysis
- Age-Based Reliability of the JCTI
- Validity and Reliability of the CCAT