FAIR Workshop on Application of Longitudinal DCMs
The interdisciplinary research area FAIR organizes a one-day workshop on Longitudinal Diagnostic Classification Models (DCMs).
In this workshop, participants will be introduced to the fundamental concepts of longitudinal DCMs, including how to model changes in latent attribute mastery over time, specify appropriate model structures, and interpret longitudinal profiles. In addition, participants will gain hands-on experience analyzing their own or example datasets using the R package TDCM, which provides functions for model specification, estimation, and visualization of longitudinal diagnostic results. The workshop will cover data preparation, model fitting, and interpretation of key outputs such as transition probabilities and individual-level mastery trajectories.
Our invited speaker is:
- Hamdollah Ravand (Vali-e-Asr University of Rafsanjan, Iran)
When and where
Date and Time: July 21, 2025, 09:00 - 16:15 CET
Location: TU Dortmund University, Mathematics building, Room M/E21, Vogelpothsweg 87, 44227 Dortmund (on-site)
Virtual: Online in Zoom (a link will be sent only to registered participants by email)
Fees
This workshop is free of charge and open to all participants; no payment is required.
How to register
Registration is necessary both for on-site and online participation. In order to register for this workshop, please fill out the following online form: https://umfragen.tu-dortmund.de/index.php/954497?lang=en
The deadline for registration is 7th July 2025.
Invited speaker
Hamdollah Ravand
Dr. Hamdollah Ravand is an Associate Professor in the English Department at Vali-e-Asr University of Rafsanjan, Iran. He teaches undergraduate and graduate courses in research methods in Teaching English as a Foreign Language, language testing, statistics and computers, and advanced writing. His primary research interests lie in language assessment, with a particular focus on the application of advanced statistical models to second language data. These include diagnostic classification models, structural equation modeling, item response theory, and multilevel modeling. He has held research appointments abroad, serving as a visiting researcher at Jena University in 2012 and at the Institute for Educational Quality Improvement (IQB) in Germany in 2016.
Abstract
An important topic in educational research is understanding how students’ knowledge and skills evolve over time, especially in response to instructional interventions. Traditional methods like gain scores offer simple measures of growth but lack robust psychometric properties. In contrast, longitudinal diagnostic classification models (DCMs) provide a more precise way to track changes in students’ mastery of specific attributes over time, providing detailed insights into individual learning trajectories. The workshop introduces key concepts of longitudinal DCMs and their use in educational assessment. Participants will learn to model changes in attribute mastery and interpret learning profiles, with hands-on practice using the R package TDCM for data preparation, model estimation, and result interpretation.
Workshop schedule
Session 1: Introduction to DCM and Longitudinal DCM (9:00 - 10:30)
- Overview of conventional and longitudinal DCMs
- Theoretical background and practical relevance to educational data analysis
Break (10:30 - 10:45)
Session 2: Model Specification and Parameter Estimation (10:45 - 12:30)
- Steps for setting up longitudinal DCMs
- Hands-on guidance on model selection and parameter estimation using sample datasets
- Software setup (e.g., R) and introductory commands for DCMs
Lunch Break (12:30 - 14:00)
Session 3: Hands-On Practical Application and Interpreting Results (14:00 - 15:30)
- Participants apply model specification techniques on a provided dataset
- Guided analysis and troubleshooting
- Discussing outcomes, interpreting results, and understanding model fit
- Application of results in longitudinal tracking of learning progress
Break (15:30 - 15:45)
Session 4: Open Q&A and Discussion (15:45 – 16:15)
- Participant questions on practical applications in their own research projects
- Short group discussion on implementation challenges and solutions
Contact
If you have any questions, please contact Farshad Effatpanah: farshad.effatpanahtu-dortmundde