Entries by Nathan Thompson, PhD

What is the Positive Manifold?

Positive manifold refers to the fact that scores on cognitive assessment tend to correlate very highly with each other, indicating a common latent dimension that is very strong.  This latent dimension became known as g for general intelligence or general cognitive ability.  This post discusses what the positive manifold is, but since there are MANY other […]


Certification and Licensure – What is the difference?

Certification and Licensure are two terms that are used quite frequently to refer to examinations that someone has to pass to demonstrate skills in a certain profession or topic.  They are quite similar, and often confused.  This is exacerbated by even more similar terms in the field, such as accreditation, credentialing, certificate, and microcredentials.  This […]

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What is an assessment / test battery?

A test battery or assessment battery is a set multiple psychometrically-distinct exams delivered in one administration.  In some cases, these are various tests that are cobbled together for related purposes, such as a psychologist testing a 8 year old child on their intelligence, anxiety, and autism spectrum.  However, in many cases it is a single […]

The Test Response Function in Item Response Theory

The Test Response Function (TRF) in item response theory (IRT) is a mathematical function that describes the relationship between the latent trait that a test is measuring, which psychometricians call theta (θ), and the predicted raw score on the test in a traditional notion (percentage/proportion/number correct).  An important concept from IRT, it provides a way […]

ASC Speaks on the SaaS Builders podcast

ASC’s CEO, Nathan Thompson PhD, was recently invited to speak on the SaaS Builders podcast hosted by Code Warriors.  Listen to Dr. Thompson talk about ASC’s next-generation software for item banking, online testing, and psychometrics, and how stronger assessment software can impact just about any industry by improving what we know about people.  ASC’s platforms […]


Classical Test Theory vs. Item Response Theory

Classical Test Theory vs. Item Response Theory: What are some key differences, and how to choose? Classical Test Theory and Item Response Theory (CTT & IRT) are the two primary psychometric paradigms.  That is, they are mathematical approaches to how tests are analyzed and scored.  They differ quite substantially in substance and complexity, even though […]

ASC Partners with CCD on Edtech in the UAE

Assessment Systems Corporation (ASC) announced today that it has signed a partnership agreement with Corporate Consultancy & Development (CCD) as an authorized representative in the United Arab Emirates.  CCD and ASC will work together to advance the field of EdTech in the UAE. Corporate Consultancy & Development is one of the leading providers of consultancy […]


Remote Proctoring Privacy Webinar

FREE WEBINAR: Privacy in the New World of Remote Proctoring ASC hosted a free webinar at Sept 9 at 9am (US Eastern), with a panel of experts discuss issues in Remote Proctoring Privacy. Rachel Schoenig: Chief Science Officer, Examity Don Kassner: CEO, MonitorEDU Dmitriy Istomin: CEO, Examus As the pandemic continues into another school year […]

Benefits of adaptive testing

Computerized adaptive testing ( CAT, adaptive testing, computer-adaptive testing, and adaptive assessment) is an AI-based technology that has existed since the 1980s. But, most assessments in the world still don’t capitalize on the benefits of adaptive testing. There is, of course, a  large body of scientific research on the topic over the past 40+ years, […]