Artificial intelligence (AI) and machine learning (ML) have become buzzwords over the past few years. As I already wrote about, they are actually old news in the field of psychometrics. Factor analysis is a classical example of ML, and item response theory (IRT) also qualifies as ML. Computerized adaptive testing (CAT) is actually an application […]
If you have worked in the field of assessment and psychometrics, you have undoubtedly encountered the word “standard.” While a relatively simple word, it has the potential to be confusing because it is used in three (and more!) completely different but very important ways. Here’s a brief discussion. Standard = Cutscore As noted by the […]
The generalized partial credit model (GPCM, Muraki 1992) is an item response theory (IRT) model designed to work with items that are partial credit. That is, instead of just right/wrong as possible, scoring an examinee can receive partial points for completing some aspects of the item correctly. For example, a typical multiple-choice item is scored […]
If you are dealing with data science, which psychometrics most definitely is, you’ve probably come across R. It is an environment that allows you to implement packages for many different types of analysis, which are built by a massive community of data scientists around the world. R has become one of the two main languages […]
Subject matter experts are an important part of the process in developing a defensible exam. There are several ways that their input is required. Here is a list from highest involvement/responsibility to lowest: Serving on the Certification Committee (if relevant) to decide important things like eligibility pathways Serving on panels for psychometric steps like Job […]
One of the most cliche phrases associated with assessment is “teaching to the test.” I’ve always hated this phrase, because it is only used in a derogatory matter, almost always by people who do not understand the basics of assessment and psychometrics. I recently saw it mentioned in this article on PISA, and that was […]
ASC has been empowering organizations to develop better assessments since 1979. Curious as to how things were back then? Below is a copy of our newsletter from 1988, long before the days of sharing news via email and social media! Our platform at the time was named MICROCAT. This later became modernized to FastTest PC […]
Item response theory is the predominant psychometric paradigm for mid or large scale assessment. As noted in my introductory blog post, it is actually a family of models. In this post, we discuss the two parameter IRT model (IRT 2PL). Consider the following 3PL equation (simplified from Hambleton & Swaminathan, 1985, Eq. 3.3). The IRT […]
Item response theory (IRT) is an extremely powerful psychometric paradigm that addresses many of the inadequacies of classical test theory (CTT). If you are new to the topic, there is a broad intro here, where you will learn that IRT is actually a family of mathematical models rather than one specific one. Today, I’m talking […]
Classical test theory is a century-old paradigm for psychometrics – using quantitative and scientific processes to develop and analyze assessments to improve their quality. (Nobody likes unfair tests!) The most basic and frequently used item statistic from classical test theory is the P-value. It is usually called item difficulty but is sometimes called item facility, […]
