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The study examines the relationship between news intensity, media sentiment and market microstructure invariance-implied measures of trading activity and liquidity of Chinese property developer stocks during the 2020–2022 Chinese property sector crisis.

The authors adopt the extension of the news article invariance hypothesis, which is a generalization of the market microstructure invariance conjecture, from January 2020 to January 2022 to test specific quantitative relationships between the arrival rate of public information, trading activity and a nonlinear function of a proxy for the probability of informed trading. Empirical tests are based on a dataset of 22,412 firm-day observations and two count-data models to correct for overdispersion and the excess number of zeros. Seventy-five stocks of Chinese companies from the property development industry (including the China Evergrande Group) were included in the sample.

The authors reject the news article invariance hypothesis but document a positive and significant relationship between the flow of public information and risk liquidity. Additionally, the authors find that the proxy for informed trading activity is positively related to the arrival rates of public information from October 2021 to January 2022.

The findings support the hypothesis that negative (positive) media sentiment induces significant deterioration (insignificant improvement) in stock liquidity. The authors find that an increase in the number of news articles about a company corresponds to a higher liquidity of Chinese property developers' stocks after controlling for media sentiment.

Provides an overview of major developments pertaining to generalized information theory during the lifetime of Kybernetes. Generalized information theory is viewed as a collection of concepts, theorems, principles, and methods for dealing with problems involving uncertainty‐based information that are beyond the narrow scope of classical information theory. Introduces well‐justified measures of uncertainty in fuzzy set theory, possibility theory, and Dempster‐Shafer theory. Shows how these measures are connected with the classical Hartley measure and Shannon entropy. Discusses basic issues regarding some principles of generalized uncertainty‐based information.

The purpose of this paper is to present a new eddy‐viscosity formulation designed to exhibit a correct response to streamline curvature and flow rotation. The formulation is implemented into a linear k‐ ε turbulence model with a two‐layer near‐wall treatment in a commercial computational fluid dynamics (CFD) solver.

A simple, robust formula is developed for the eddy‐viscosity that is curvature/rotation sensitive and also satisfies realizability and invariance principles. The new model is tested on several two‐ and three‐dimensional problems, including rotating channel flow, U‐bend flow and internally cooled turbine airfoil conjugate heat transfer. Predictions are compared to those with popular eddy‐viscosity models.

Converged solutions to a variety of turbulent flow problems are obtained with no additional computational expense over existing two‐equation models. In all cases, results with the new model are superior to two other popular k‐ ε model variants, especially for regions in which rapid rotation or strong streamline curvature exists.

The approach adopted here for linear eddy‐viscosity models may be extended in a straightforward manner to non‐linear eddy‐viscosity or explicit algebraic stress models.

The new model is a simple “plug‐in” formula that contains important physics not included in most linear eddy‐viscosity models and is easy to implement in most flow solvers.

The present model for curved and rotating flows is developed without the need for second derivatives of velocity in the formulation, which are known to present difficulties with unstructured meshes.

The purpose of this paper is to discuss the complexity of – and conflicts inherent in – managing sports leagues at both the league and franchise level.

The paper draws on changes to the National Basketball Association's (NBA) amateur entry draft, which has attempted to balance the need to preserve league parity and reduce the incentive for teams to deliberately lose games in order to improve draft position.

The discussion reveals the conflict between league and team goals. In addition, using Oliver's strategic decisions as a framework, the findings also illustrate how sport league commissioners have to balance pressures from both the internal and external environments.

This paper expands our understanding of how leagues manage institutional pressures, and how these pressures impact the team, leagues, and the decision makers involved.

Standard financial risk management practices proved unable to provide an adequate understanding and a timely warning of the financial crisis. In particular, the theoretical foundations of risk management and the statistical calibration of risk models are called into question. Policy makers and practitioners respond by looking for new analytical approaches and tools to identify and address new sources of financial risk. Financial markets satisfy reasonable criteria of being considered complex adaptive systems, characterized by complex financial instruments and complex interactions among market actors. Policy makers and practitioners need to take both a micro and macro view of financial risk, identify proper transparency requirements on complex instruments, develop dynamic models of information generation that best approximate observed financial outcomes, and identify and address the causes and consequences of systemic risk. Complexity analysis can make a useful contribution. However, the methodological suitability of complexity theory for financial systems and by extension for risk management is still debatable. Alternative models drawn from the natural sciences and evolutionary theory are proposed.

The invariance principle known as the functional central limit theorem is the fundamental knowledge for understanding the convergence of a Markov chain to a diffusion process and has been applied to many areas of financial economics. The derivation of that principle from the properties of stochastic process is nasty (Billingsley, 1999). Following the approach of Gikhman and Skorokhod (2000) this study uses the properties of probability measures to simplify the proof of the principle. If the sequences of finite distributions on weakly converge then they are tight. Using this properties, the invariance principle was directly proved. As applications of this principle, I derived the statistic of unit root process and the convergence of the Cox et al. (1979) binomial option pricing model to the continuous time Black Scholes (1972) option pricing model.

The literature indicates the advantages of decisions formulated through intuition, as well as the limitations, such as lack of consistency in similar situations. The principle of consistency (invariance), requiring that two equivalent versions of choice‐problems will produce the same preference, is violated in intuitive judgment. This paper aims to examine the contribution of the simple decision process (SDP) to invariance in intuitive educational decisions. The SDP integrates intuitive and systematic techniques by breaking down a dilemma into simple problems that can be processed intuitively with little or no perturbation by bias.

In total, 40 teachers resolved a complex educational dilemma three times intuitively, with the same data presented in a different order in each iteration. Content analysis revealed inconsistency in the conclusions reached with the three formats. This is explained in the literature by the anchoring effect. Thereafter, the three‐step procedure was repeated, with the participation of 246 teachers using SDP. A statistical analysis showed significant invariance with respect to decisions made during the three trials.

An SDP formulated decision is not affected by the order of data presentation. The principle of invariance, a sine qua non in analyzing rational choices, is maintained

The article sheds light on the potential inherent in integration of intuition and common sense with analytical thought‐patterns in educational decisions and in other fields that involve probabilistic determinations.

Purpose: Most of the characterizations of inequality or poverty indices assume some invariance condition, be that scale, translation, or intermediate, which imposes value judgments on the measurement. In the unidimensional approach, Zheng (2007a, 2007b) suggests replacing all these properties with the unit-consistency axiom, which requires that the inequality or poverty rankings, rather than their cardinal values, are not altered when income is measured in different monetary units. The aim of this paper is to introduce a multidimensional generalization of this axiom and characterize classes of multidimensional inequality and poverty measures that are unit consistent.

Design/methodology/approach: Zheng (2007a, 2007b) characterizes families of inequality and poverty measures that fulfil the unit-consistency axiom. Tsui (1999, 2002), in turn, derives families of the multidimensional relative inequality and poverty measures. Both of these contributions are the background taken to achieve our characterization results.

Findings: This paper merges these two generalizations to identify the canonical forms of all the multidimensional subgroup- and unit-consistent inequality and poverty measures. The inequality families we derive are generalizations of both the Zheng and Tsui inequality families. The poverty indices presented are generalizations of Tsui's relative poverty families as well as the families identified by Zheng.

Originality/value: The inequality and poverty families characterized in this paper are unit and subgroup consistent, both of them being appropriate requirements in empirical applications in which inequality or poverty in a population split into groups is measured. Then, in empirical applications, it makes sense to choose measures from the families we derive.

Social mobility is an issue at the crossroad of various disciplines: sociology, statistics, political science and economics. We review alternative approaches to the analysis of intergenerational income mobility, and conduct a questionnaire aimed to reveal students’ opinions on some basic principles developed in the literature. The questionnaire includes questions focussed on: (a) the difference between structural and exchange mobility; (b) the decomposition of mobility tables into parameters linked to structural mobility and parameters linked to exchange mobility; (c) the effects of transformations of the status variables (incomes) on mobility comparisons. These issues have been formalized as hypotheses that can be formally tested by the questionnaire. We find various regularities in the data, but also some rejections of basic principles that require further scrutiny.

The purpose of this paper is to investigate the body-mind problem from a mathematical invariance principle in relation to personality dynamics in the psychological and the biological levels of description.

The relationship between the two mentioned levels of description is provided by two mathematical models as follows: the response model and the bridge model. The response model (an integro-differential equation) is capable to reproduce the personality dynamics as a consequence of a determined stimulus. The invariance principle asserts that the response model can reproduce personality dynamics at the two levels of description. The bridge model (a second-order partial differential equation) can be deduced as a consequence of this principle: it provides the co-evolution of the general factor of personality (GFP) (mind), the it is an immediate early gene (c-fos) and D3 dopamine receptor gene (DRD3) gens and the glutamate neurotransmitter (body).

An application case is presented by setting up two experimental designs: a previous pilot AB pseudo-experimental design (AB) pseudo-experimental design with one subject and a subsequent ABC experimental design (ABC) experimental design with another subject. The stimulus used is the stimulant drug methylphenidate. The response and bridge models are validated with the outcomes of these experiments.

The mathematical approach here presented is based on a holistic personality model developed in the past few years: the unique trait personality theory, which claims for a single personality trait to understand the overall human personality: the GFP.