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RUMM 2030+

Presenter: David Andrich (The University of Western Australia)

Monday, April 10, 2023, 8:00 am-9:00 am (CDT)


Description: This workshop aims to introduce the participants to RUMM2030+ program. Rumm2030 Plus is a complete implementation of the Rasch Measurement Theory.

ConQuest 5

Presenter: Perman Gochyyev (UC Berkeley)

Monday, April 10, 2023, 9:15 am-11:15 am (CDT)



ACER ConQuest is a computer program for fitting both unidimensional and multidimensional item response and latent regression models. It provides data analysis based on a comprehensive and flexible range of item response models (IRM), allowing examination of the properties of performance assessments, traditional assessments and rating scales. ACER ConQuest also offers wider measurement and research community analysis procedures based on the most up-to-date psychometric methods of multifaceted item response models, multidimensional item response models, latent regression models and drawing plausible values. In this workshop, we will cover the fundamentals necessary to start using ConQuest for various analyses. Participants are expected to have ConQuest 5 trial version downloaded and installed (available for both Mac and PC). ACER ConQuest 5 is available for download as a free 30-day trial.

Berkeley Assessment System Software/BASS

Presenter: David Torres Irribarra (Pontificia Universidad Católica de Chile)

Monday, April 10, 2023, 11:30 am-1:30 pm (CDT)


Description: The BEAR Assessment System Software (BASS) encompasses a theoretical basis for the domain modeling logic, and offers tools for development, delivery, scoring, reporting and use of learning evidence. Specifically, BASS employs the UC Berkeley BEAR Assessment System (BAS) to coordinate the instrumentation with the domain modeling, which is a four-part approach to modeling that involves a combined domain and student model (Wilson, 2005). The structure of the software system is designed to highlight the four parts of the BAS, and to allow educational practitioners and developers to implement the processes. In this workshop, we provide hands-on activities with the software BASS 2.0 while we cover its theoretical bases of construct mapping of the domain and student models, and how these serve as a basis for the “full cycle” of instrument development, deployment and reporting. Participants will learn how the software enables practitioners and developers to implement the full range of assessment processes.


Estimation and applications of a specialized mixture IRT model and its extensions in Mplus

Presenter: Minjeong Jeon (UCLA)

Monday, April 10, 2023, 2:00 pm-4:00 pm (CDT)

Description: Finite mixture models have been widely utilized in IRT analysis for studying sub-populations (or latent classes) of respondents and/or items. While most applications of mixture models in IRT seem to serve on exploratory purposes, e.g., for identifying the number and nature of latent classes, confirmatory uses of mixture models have also been found to be useful. In this workshop, I will focus on a special type of confirmatory mixture IRT model, called the Saltus model (Wilson, 1989). The original Saltus model was developed in the context of investigating children’s differential developmental stages. In this workshop, I will show that this useful model can be utilized for broader applications. I will explain that the Saltus model can be modified and parameterized as a constrained mixture model, and show how the original model can be extended in a variety of ways and applied in a wide range of situations. Estimation of the Saltus model and its extensions will be demonstrated with Mplus. 

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