Our team consists of the following researchers:
prof. dr. Jelte M. Wicherts
Jelte Wicherts (1976) received both his Master’s degree (2002, cum laude) and PhD degree (2007, cum laude) from the Psychological Methods group at the University of Amsterdam. He has published on a wide range of topics related to reproducibility, replication, individual differences, statistics, and measurement. His research interests include group differences in IQ, reproducibility, biases in research, measurement invariance, stereotype threat, the Flynn Effect, structural equation modeling, errors with statistics, and data sharing. He is (co)author of 85 publications in various peer-reviewed journals, including Intelligence, Proceedings of the Royal Society: B, Journal of Personality and Social Psychology, Perspectives on Psychological Science, Learning and Individual Differences, Structural Equation Modeling, Behavior Research Methods, Psychological Methods, Psychological Science, PLoS ONE, and Nature. He has reviewed for 34 different journals and is an editorial board member of the journals Psychological Science, Intelligence, Psychological Methods, and the Journal of Health Psychology. He is an Academic Editor at PLOS ONE and an associate editor at Frontiers in Quantitative Psychology and Measurement. From 2007-2012 he was an assistant professor at the University of Amsterdam. From 2012-2017 he was an Associate Professor at the Department of Methodology and Statistics at Tilburg University. In 2017 he became full professor in methodology of the social and behavioral sciences at the same department. He has acquired Open Competition (200K Euros) VENI (208K) and VIDI (800K) grants from the Netherlands Organization for Scientific Research (NWO) and a Consolidator grant (2000k) from the European Research Council. He is affiliate member of the Meta-Research Innovation Center at Stanford (METRICS).
prof. dr. Marcel A. L. M. van Assen
Marcel van Assen (1972) is currently assistant professor at the department of Methodology and Statistics of Tilburg University, and is professor by special appointment at the Department of Sociology of Utrecht University, where he holds the endowed chair “Mathematical Sociology”.
He studied mathematical psychology at Radboud University (1996, cum laude), and obtained his PhD at Groningen University (2001, cum laude) after writing an interdisciplinary dissertation on the intersection of psychology, economics, and sociology.
He has more than fifty peer-reviewed publications on the following diverse range of topics:
meta-analysis, publication bias, game theory, social networks, individual decision making, collective decision making, social dilemmas, prisoner’s dilemma, exchange, exchange networks, research misconduct, errors with statistics, replication, psychometrics, auditory perception, visual perception, frailty, and secrets.
dr. Marjan Bakker – Assistant Professor
Marjan Bakker obtained her PhD (2014) in psychological methods from the University of Amsterdam and is currently assistant professor of methodology and statistics at the Tilburg School of Social and Behavioral Sciences at Tilburg University. Her dissertation is titled “Good science, bad science: Questioning Research Practices in Psychology”, and her research interests are scientific integrity, errors in statistics, statistical power, publication bias, preregistration, blind analysis, and psychometrics. She has published many highly cited papers that contributed to the current reproducibility debate in psychology.
Coosje L. S. Veldkamp – PhD Student
Coosje obtained her Research Master’s degree in Psychology from the University of Amsterdam, specializing in Social Psychology and Developmental Psychology. Her doctoral research focuses on the effectiveness of methods aimed at reducing human error and bias in science, on trust in and among scientists, and on the psychology of the scientist in general. She co-chaired the committee that organized the international symposium Human Factors in Science in 2014, featuring highly influential scientists in the field of meta-research (see here).
Michèle B. Nuijten – PhD Student
Michèle studied Psychology at the University of Amsterdam, where she specialized in research methods. Since 2012 she has been working on her doctoral dissertation at Tilburg University under supervision of Jelte Wicherts and Marcel van Assen. Her projects include topics such as publication bias, replication, and statistical reporting errors. Among other things she co-developed the R package “statcheck” that extracts statistical results from articles and recomputes p-values.
Paulette C. Flore – PhD Student
In 2013 Paulette obtained her Research Master degree in Social and Behavioral Sciences from Tilburg University (minor social psychology/methodology and statistics). Since then she worked under supervision of Jelte Wicherts and Daniel Oberski on her dissertation with the working title “the psychometrics of stereotype threat”. The focus of her studies lies on experimental social psychology, gender stereotype threat, meta-analysis, replications, and differential item functioning.
Robbie C. M. van Aert – PhD Student
After Robbie finished Research Master in Social and Behavioral Sciences (minor methodology and statistics/social sciences) at Tilburg University, he started my PhD at the department of methodology and statistics in Tilburg. Robbie’s dissertation is about conducting meta-analysis in the presence of publication bias and questionable research practices. His research interests encompass everything what has to do with statistical methods for meta-analyses.
Chris H. J Hartgerink – PhD Student
Chris Hartgerink is a PhD candidate specializing in detecting potentially problematic data in the social and medical sciences, caused by for example data fabrication. He develops and validates detection methods based on summary results and raw data, which can be applied to estimate prevalence of problematic data at the paper level. Besides this, he is specialized in R development, webscraping, text-mining, transparent research, research integrity, and Open Access of scholarly articles. He is a signee of the Hague declaration to promote text-mining and the Declaration of Research Assessment to promote the use of scientifically validated indices to evaluate scholars (and not the unscientific Impact Factor).
Hilde E. M. Augusteijn – PhD Student
During her research master in communication and information sciences Hilde’s interest in meta-analysis grew stronger, along with her amazement about publication bias and questionable research practices.
Hilde’s current PhD project combines these interests: Developing meta-analystic methods that correct for publication bias and p-hacking when estimating effect sizes, heterogeneity and moderator effects.
Having her own roots in practical research, Hilde hopes to expand the toolbox of meta-analysts in a way that will help and improve their work.
Olmo van den Akker – PhD Student
Olmo’s academic education took place at the University of Amsterdam, where he obtained a Master degree in Behavioral Economics and Game Theory as well as a Research Master degree in Psychology. During his studies he realized that the social sciences are not functioning as well as they should and that there are issues at both the institutional level and at the level of individual researchers. In his PhD-project, Olmo mainly focuses on the latter by studying researchers’ ideas about nonsignificant results, meta-analytic results, and the complexities of preregistration. Other research interests of Olmo include evolutionary psychology, human cooperation, and network analysis.