This book 'Essays on Contemporary Psychometrics' provides an overview of contemporary psychometrics, the science devoted to the advancement of quantitative measurement practices in psychology, education and the social sciences. The volume consists of four parts, each having several chapters on cutting-edge work in the field. Part I, General Perspectives on Psychometrics, includes expert views on topics such as psychological models vs. measurement models, using tests in decision making, artificial intelligence, and psychometric network models. Part II, Factor Analysis and Classical Test Theory, the type of psychometrics that is still used most often in the social and behavioral sciences, includes state-of-the-art contributions on test-score reliability, change-score reliability, handling missing data in principal component analysis, test equating, and conditional standard errors of measurement. Part III, Item Response Theory, the leading form of psychometrics in modern educational measurement, includes discussions of sampling from many conditional distributions, transparent score reporting, nonparametric item response theory, and targeted testing. Part IV, New Psychometrics, discusses recently developed ideas beyond classical test theory and item response theory, including topics related to computer adaptive testing, response-time modelling, validity indices, diagnostic classification models, and the sparse latent class model for ordinal measurements.

Together, these four parts provide an overview of the current state-of-the-art in psychometrics in educational measurement. They are a valuable source of information for graduate students who (intend to) study psychometrics and need an overview of the field, and for researchers interested in the current developments in the field.

Chapters [3], [5], [8], [16] and [19] are available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

L. Andries van der Ark is full professor of psychometrics at the research institute of Child Development and Education at the University of Amsterdam, and director of the Graduate School of Child Development and Education at the University of Amsterdam. He has over 100 refereed publications since 1997 (H-index 35), including two monographs. His research interests include statistical solutions to practical data problems, such as handling missing data, handling outliers, and norming test scores; construction of psychological and educational tests; nonparametric item response theory, including Mokken scale analysis; categorical marginal models and their application to test data; and software development for psychometrics. He has been the editor of five volumes in the Springer Proceedings in Mathematics & Statistics series (Millsap et al., 2014, 2015; Van der Ark et al, 2015, 2016, 2017) and one volume in Erlbaum's Quantitative Methodology Series (Van der Ark et al., 2005). He has been associate editor of the Journal of Educational Measurement (2013-2016), guest editor of the journals Methodology (2010) and Quality of Life Research (2020-2021), and ad-hoc reviewer for over 50 scientific journals, publishers, and grant providers. He has been in the editorial board of the International Journal of Testing (2015-2016). Recently, he finished a monograph (together with Klaas Sijtsma) on measurement models for psychological attributes (Sijtsma & Van der Ark, 2020) with Chapman & Hall/CRC.

Wilco H.M. Emons is currently senior scientific researcher at the Department of Research & Innovation of Cito (National Institute of Educational Measurement) in the Netherlands. Prior to his transfer to Cito in 2019 he worke d for 15 years as an assistant professor (tenured) at Tilburg University. His main research interests include test construction, (computational) psychometrics, educational testing, (research) ethics, and longitudinal assessment. He is involved in over 60 refereed publications (articles, book chapters) since 2001 and presented his work on many conferences worldwide. He has been member of Dutch Committee of Tests and Testing in the Netherlands for eight years and has been involved as a methodologist in different steering groups for Dutch ministries.

Rob R. Meijer is full professor of Psychometrics and Statistics at the University of Groningen. He studied I/O psychology and did his Ph.D thesis on items response theory. His main interests are in psychological and educational testing and methods to improve the quality of tests. His latest research is concerned with in the use of tests in decision making and personnel selection. He published over 100 paper papers in international journals on psychometric topics, personnel an educational selection, and test use. He supervised over 20 PhD theses.He has been on the editorial board of Psychological Methods and Journal of Educational Measurement and Editor of the International Journal of Testing and is now on the editorial board of the journals Assessment, Journal of Personality Assessment and International Journal of Testing. Furthermore he is director of the Interuniversity Graduate School of Psychometrics and Sociometrics (IOPS).