Entries by Nathan Thompson, PhD

What is a psychometrician? Are they created equal?

A psychometrician is someone who practices psychometrics – the Science of Assessment.  That is, they are familiar with the scientific literature devoted to the development of fair, high-quality assessments, and they use this knowledge to improve assessments.  Psychometricians learn about many different topics, and can take a number of slants, such as applied vs. academic, […]

What do “dichotomous” and “polytomous” mean in IRT?

Item response theory (IRT) is the dominant psychometric paradigm for constructing, scoring, and analyzing assessments.  Virtually all large-scale assessments utilize IRT because of its well-documented advantages.  In many cases, however, it is referred to as a single way of analyzing data.  However, IRT is actually a family of models, and a growing family at that. […]

US Dept of Defense Requires that Military Certifications be Accredited

The United States Congress recently passed the 2016 National Defense Authorization Act.  This provides policies and authorizations for 2016 but no budgetary appropriations, which is done with subsequent legislation.  While these Acts and related ones happen all the time, they rarely have direct impact on the field of testing and assessment. This one is different. There […]

2016 – A Year of Growth!

2015 was an incredible year that witnessed extensive changes at Assessment Systems! CERTIFIOR REBUILT Certifior, our credentialing management platform, was substantially rebuilt with a number of new modules, including Recertification and CE tracking.  Certifior allows organizations to easily manage all kinds of credentialing programs: certification, certificates, recertification exams, practice exams, microcredentials, and state-based licensure.  Visit […]

Doing it Right: Essentials for Online Testing

If you are looking around for an online testing system, you have certainly discovered there are many out there.  How do you choose?  Well, for starters, it is important to understand that the range of quality and sophistication is incredible.  This post will help you identify some salient features and benefits that you should consider […]

Interpreting item statistics from classical test theory

Our psychometric software is widely used around the world, and I often receive questions on how to interpret the output.  Below is a discussion on interpreting item statistics from classical test tehory, adapted from the Iteman manual.  We will be publishing additional posts on other topics like distractor analysis and item response theory, but you can […]

10 ways to improve your assessment with psychometrics

Education, to me, is the neverending opportunities we have for a cycle of instruction and assessment.    This can be extremely small scale (watching a YouTube video on how to change a bike tire, then doing it) to large scale (teaching a 5th grad math curriculum and then assessing it nationwide).  Psychometrics is the Science of […]

Interpreting IRT cutscores

Some time ago, I received this question regarding interpreting IRT cutscores (item response theory): In my examination system, we are currently labeling ‘FAIL’ for student’s mark with below 50% and ‘PASS’ for 50% and above.  I found that this amazing Xcalibre software can classify students’ achievement in 2 groups based on scores.  But, when I […]