Model Selection of Nested and Non-Nested Item Response Models Using Vuong Tests

Abstract

In this paper, we apply Vuong’s general approach of model selection to the comparison of nested and non-nested unidimensional and multidimensional item response theory (IRT) models. Vuong’s approach of model selection is useful because it allows for formal statistical tests of both nested and non-nested models. However, only the test of non-nested models has been applied in the context of IRT models to date. After summarizing the statistical theory underlying the tests, we investigate the performance of all three distinct Vuong tests in the context of IRT models using simulation studies and real data. In the non-nested case we observed that the tests can reliably distinguish between the graded response model and the generalized partial credit model. In the nested case, we observed that the tests typically perform as well as or sometimes better than the traditional likelihood ratio test. Based on these results, we argue that Vuong’s approach provides a useful set of tools for researchers and practitioners to effectively compare competing nested and non-nested IRT models.     

Spinoza's PSR as a Principle of Clear and Distinct Representation

It is argued first, that Spinoza's Principle of Sufficient Reason (PSR) is best seen as an auxiliary premise and not as an axiom of the Ethics; second, that Spinoza held the PSR to be a self‐evident truth that indicates a necessary condition for clearly and distinctly representing the existence or non‐existence of a thing; and third, that this interpretation of Spinoza's PSR explains the near absence of the PSR within the demonstrations of the Ethics as well as the importance of the principle in Spinoza's thought.     

The Role of Contiguity in Free-Operant Unsignaled Delay of Positive Reinforcement: A Brief Review

The Psychological Record - The temporal contiguity between responses and consequences is an important variable in operant conditioning. This paper examines a selected portion of the empirical...