Neo-Classical Test Theory: A Modernization

Abstract

Classical test theory has been ascribed the status of weak theory. Early development reflected a native realism, with variables being operationally defined. Subsequent developments in mathematics, statistics, and structural modeling, however, have rendered classical test theory problematic. Yet the basic framework is sound. Decomposition of an observed score into the sum of a true and an error component is inherently meaningful. What is required is a modernization that addresses past exclusions and deficiencies while retaining the classical framework. Consequently, a neo-classical test theory formalized as fourteen tenets is presented. Each tenet is accompanied by an elaborative discussion. Benefits accruing from and costs associated with theory modernization are discussed. Educational and developmental implications for three user types are identified.

Symptoms Measurement, Community Sampling and the Zero-Problem: A Case for Two-Part Modeling

“…The problem is that zero cannot simultaneously be ascribed both a categorical and a dimensional representation within a generative experiment. Readers are encouraged to refer to [2] for a discussion of experiment as a generative process. If zero is used to designate a class, the distinction between zero and non-zero is qualitative.…”

“…As previously argued, the symptom measurement model can be expressed as ln Y f µ λ ε = + + , which follows neo-classical test theory [2] in form with the exception that the observed variable Y is logarithmically transformed. As f and e in the pathology measurement model are defined as independent normally distributed random variables, ln Y as a weighted sum of normally distributed variables is itself normally distributed.…”

“…The distinction between human ability and human health measurement is most apparent when examining the comparative meaning of classical true score and true symptom. As both neoclassical true score and true symptom can be considered as mapping of an experimental probability space to real numbers [2], their difference must reside in the nature of the underlying generative experiment. For a more comprehensive discussion, the reader is referred to [2, Tenet 1].…”

“…Symptoms as latent variables. The premise of this paper is that neo-true score theory [2] can be meaningfully applied to psychopathological symptoms measurement. At the core is the axiom that an observed symptom score can be decomposed into a true-score and an error-score component.…”

“…Symptoms as self-reported feelings of abnormality play a critical role in psychopathological diagnosis and assessment. Symptoms considered as overt manifestations of an underlying pathological state [1] differ from traits in that symptoms can be meaningfully reported as present or absent, whereas traits are generally considered to be ever present in some positive amount [2]. This distinction is central to an understanding of the inherent difference between human health and human ability measurement.…”