Book Review of Rasch Models for Solving Measurement Problems: Invariant Measurement in the Social Sciences by Engelhard Jr. and Wang

As a paradigm shift from classical test theory, Rasch measurement theory introduces a framework of scales that is capable of producing invariant measurement, which plays an increasingly important role in solving practical measurement problems in the social sciences, psychometrics, and health sciences. Researchers have increasingly adopted Rasch measurement to develop and validate scales in a variety of educational and psychological contexts (e.g. Mendoza Yan, 2021; Yan Pastore, 2022). Rasch measurement is often used in the validation of scales in conjunction with structural equation models (SEM), which provide meaningful answers to a variety of measurement questions. However, it remains unfamiliar to many researchers, practitioners, and educators who have embraced classical test theory

Mean Square Capacity of Power Constrained Fading Channels with Causal Encoders and Decoders

This paper is concerned with the mean square stabilization problem of discrete-time LTI systems over a power constrained fading channel. Different from existing research works, the channel considered in this paper suffers from both fading and additive noises. We allow any form of causal channel encoders/decoders, unlike linear encoders/decoders commonly studied in the literature. Sufficient conditions and necessary conditions for the mean square stabilizability are given in terms of channel parameters such as transmission power and fading and additive noise statistics in relation to the unstable eigenvalues of the open-loop system matrix. The corresponding mean square capacity of the power constrained fading channel under causal encoders/decoders is given. It is proved that this mean square capacity is smaller than the corresponding Shannon channel capacity. In the end, numerical examples are presented, which demonstrate that the causal encoders/decoders render less restrictive stabilizability conditions than those under linear encoders/decoders studied in the existing works.Comment: Accepted by the 54th IEEE Conference on Decision and Contro