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Psychology

D-Index
65
Citations
17521
World Ranking
2820
National Ranking
145

Overview

Klaas Sijtsma is affiliated with Tilburg University in the Netherlands and has contributed extensively to the fields of mathematics and decision sciences. Their research primarily spans the domains of psychometric methodologies, statistical modeling, and inference.

The scientist's main areas of study include:

  • Mathematics
  • Decision Sciences

Subfields of focus in Sijtsma's research involve:

  • Statistics and Probability
  • Management Science and Operations Research
  • Computer Networks and Communications
  • Experimental and Cognitive Psychology
  • Artificial Intelligence

Key topics addressed across their publications cover:

  • Psychometric Methodologies and Testing
  • Advanced Statistical Modeling Techniques
  • Statistical Methods and Bayesian Inference
  • Advanced Statistical Methods and Models
  • Mental Health Research Topics
  • Statistical Methods and Inference
  • Sensory Analysis and Statistical Methods

Sijtsma has authored multiple papers in well-regarded academic venues. Frequent publication outlets are:

  • Psychometrika
  • arXiv (Cornell University)
  • Behavior Research Methods
  • Accountability in Research
  • Computers & Education

Notable recent publications include:

  • Part II: On the Use, the Misuse, and the Very Limited Usefulness of Cronbach's Alpha: Discussing Lower Bounds and Correlated Errors (2021, Psychometrika)
  • Recognize the Value of the Sum Score, Psychometrics' Greatest Accomplishment (2024, Psychometrika)

The scientist collaborates frequently with several co-authors, including:

  • Jules L. Ellis
  • Julius M. Pfadt
  • Edoardo Costantini
  • Kyle M. Lang
  • Wilco H. M. Emons

The scope of Klaas Sijtsma's work situates at the intersection of statistical theory and practical psychometric testing, contributing to improved understanding and application of reliability metrics and advanced modeling strategies within behavioral and decision sciences contexts.

Best Publications

  • On the Use, the Misuse, and the Very Limited Usefulness of Cronbach’s Alpha

    Klaas Sijtsma

  • Cognitive Assessment Models with Few Assumptions, and Connections with Nonparametric Item Response Theory:

    Brian W. Junker;Klaas Sijtsma

  • Introduction to Nonparametric Item Response Theory

    Klaas Sijtsma;Ivo Molenaar

  • Methodology Review : Evaluating Person Fit

    Rob R. Meijer;Klaas Sijtsma

  • Examination of the dimensionality of fatigue: The construction of the Fatigue Assessment Scale (FAS)

    Helen J. Michielsen;Jolanda De Vries;Guus L. Van Heck;Fons J.R. Van de Vijver

  • MSP5 for Windows User's Manual

    W. Molenaar;K. Sijtsma

  • Big Five personality stability, change, and codevelopment across adolescence and early adulthood.

    Jeroen Borghuis;Jaap J A Denissen;Daniel Oberski;Klaas Sijtsma

  • Invited discussion of Cronbach (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16, 297-334 (26,889 citations in Google Scholar as of 1/1/2016)

    Klaas Sijtsma

  • A tutorial on how to do a Mokken scale analysis on your test and questionnaire data

    Klaas Sijtsma;L. Andries van der Ark

  • Influence of Imputation and EM Methods on Factor Analysis When Item Nonresponse in Questionnaire Data Is Nonignorable.

    Coen A. Bernaards;Klaas Sijtsma

  • Testtheorie: Inleiding in de theorie van de psychologische test en zijn toepassingen

    P.J.D. Drenth;K. Sijtsma

  • Investigation and Treatment of Missing Item Scores in Test and Questionnaire Data.

    Klaas Sijtsma;L. Andries van der Ark

  • MPS5 for Windows. A program for Mokken scale analysis for polytomous items

    I.W. Molenaar;K. Sijtsma

  • On the Shortcomings of Shortened Tests: A Literature Review

    Peter M. Kruyen;Wilco H. M. Emons;Klaas Sijtsma

  • Stochastic ordering using the latent trait and the sum score in polytomous IRT models

    Bas T. Hemker;Klaas Sijtsma;Ivo W. Molenaar;Brian W. Junker

  • Reliability Beyond Theory and Into Practice

    Klaas Sijtsma

  • Selection of Unidimensional Scales From a Multidimensional Item Bank in the Polytomous Mokken IRT Model

    Bas T. Hemker;Klaas Sijtsma;Ivo W. Molenaar

  • COTAN Beoordelingssysteem voor de kwaliteit van tests, geheel herziene versie

    A. Evers;W. Lucassen;R. R. Meijer;K. Sijtsma

  • On the consistency of individual classification using short scales

    Wilco H. M. Emons;Klaas Sijtsma;Rob R. Meijer

  • Investigating an invariant item ordering for polytomously scored items

    Rudy Ligtvoet;L.Andries van der Ark;Janneke M. te Marvelde;Klaas Sijtsma

Frequent Co-Authors

Wim Meeus
Wim Meeus Utrecht University
Jaap J. A. Denissen
Jaap J. A. Denissen Utrecht University
Susan Branje
Susan Branje Utrecht University
Wiebke Bleidorn
Wiebke Bleidorn University of Zurich
Susanne S. Pedersen
Susanne S. Pedersen University of Southern Denmark
Ad J. J. M. Vingerhoets
Ad J. J. M. Vingerhoets Tilburg University
Erik J. Giltay
Erik J. Giltay Leiden University Medical Center
John J. McArdle
John J. McArdle University of Southern California
Hans M. Koot
Hans M. Koot Vrije Universiteit Amsterdam
Ivan Nyklíček
Ivan Nyklíček Tilburg University

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