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, Certificate, and Licensure are terms that are used quite frequently to refer to credentialing 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, badge, and microcredentials. This […]
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 (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 […]
If you are delivering high-stakes tests in linear forms – or piloting a bank for CAT/LOFT – you are faced with the issue of how to equate the forms together. That is, how can we defensibly translate a score on Form A to a score on Form B? While the concept is simple, the methodology […]
Linear on the fly testing (LOFT) is an approach to assessment delivery that increases test security by limiting item exposure. It tries to balance the advantages of linear testing (e.g., everyone sees the same number of items, which feels fairer) with the advantages of algorithmic exams (e.g., creating a unique test for everyone). In general, […]
The two terms Norm-Referenced and Criterion-Referenced are commonly used to describe tests, exams, and assessments. They are often some of the first concepts learned when studying assessment and psychometrics. Norm-referenced means that we are referencing how your score compares to other people. Criterion-referenced means that we are referencing how your score compares to a criterion such as […]
The item-total point-biserial correlation is a common psychometric index regarding the quality of a test item, namely how well it differentiates between examinees with high vs low ability. What is item discrimination? While the word “discrimination” has a negative connotation, it is actually a really good thing for an item to have. It means that […]
The California Department of Human Resources (CalHR, calhr.ca.gov/) has selected Assessment Systems Corporation (ASC, assess.com) as its vendor for an online assessment platform. CalHR is responsible for the personnel selection and hiring of many job roles for the State, and delivers hundreds of thousands of tests per year to job applicants. CalHR seeks to migrate to a […]
Nathan Thompson, Ph.D., was recently invited to talk about ASC and the future of educational assessment on the Ednorth EdTech Podcast. EdNorth is an association dedicated to continuing the long history of innovation in educational technology that has been rooted in the Twin Cities of Minnesota (Minneapolis / Saint Paul). Click below to listen online, […]
