This book provides a concise introduction to the topic of the Rasch model, which has become relatively well-known since it was used in the PISA study. In addition to a clear presentation of the underlying theory, the book also offers a practical introduction to fitting Rasch models by means of the freely available statistical software R.

1 Introduction 2 The Rasch Model 3 Parameter Estimation 4 Test Evaluation 5 Basic R Usage 6 R Package eRm 7 R Package mirt 8 R Package TAM 9 R Interface to Stan 10 Extensions to the Rasch Model 11 Models for Polytomous Responses 12 Outlook on Special Applications

Rudolf Debelak is a Senior Researcher at the University of Zurich, Switzerland. His research interests include psychometrics, with a focus on item response theory, machine learning, and the mathematical and statistical foundations of psychological research methods. Before working in academia, he was employed in the psychological test industry for several years.

Carolin Strobl is a Professor of Psychological Methods at the University of Zurich, Switzerland. Her research spans psychometrics, statistics and machine learning. She has been teaching introductory and advanced courses on statistics and psychometrics for many years and received the 2018 teaching award from her department's student council.

Matthew Zeigenfuse currently works as a data scientist. He spent many years working in academia, researching and teaching cognitive science, psychometrics and Bayesian statistics in both the US and Switzerland.