Admissibility in Finitely Generated Quasivarieties

Checking the admissibility of quasiequations in a finitely generated (i.e., generated by a finite set of finite algebras) quasivariety Q amounts to checking validity in a suitable finite free algebra of the quasivariety, and is therefore decidable. However, since free algebras may be large even for small sets of small algebras and very few generators, this naive method for checking admissibility in \Q is not computationally feasible. In this paper, algorithms are introduced that generate a minimal (with respect to a multiset well-ordering on their cardinalities) finite set of algebras such that the validity of a quasiequation in this set corresponds to admissibility of the quasiequation in Q. In particular, structural completeness (validity and admissibility coincide) and almost structural completeness (validity and admissibility coincide for quasiequations with unifiable premises) can be checked. The algorithms are illustrated with a selection of well-known finitely generated quasivarieties, and adapted to handle also admissibility of rules in finite-valued logics

A theory of structural model validity in simulation.

During the last decennia, the practice of simulation has become increasingly popular among many system analysts, model builders and general scientists for the purpose of studying complex systems that surpass the operability of analytical solution techniques. As a consequence of the pragmatic orientation of simulation, a vital stage for a successful application is the issue of validating a constructed simulation model. Employing the model as an effective instrument for assessing the benefit of structural changes or for predicting future observations makes validation an essential part of any productive simulation study. The diversity of the employment field of simulation however brings about that there exists an irrefutable level of ambiguity concerning the principal subject of this validation process. Further, the literature has come up with a plethora of ad hoc validation techniques that have mostly been inherited from standard statistical analysis. It lies within the aim of this paper to reflect on the issue of validation in simulation and to present the reader with a topological parallelism of the classical philosophical polarity of objectivism versus relativism. First, we will position validation in relation to verification and accreditation and elaborate on the prime actors in validation, i.e. a conceptual model, a formal model and behaviour. Next, we will formally derive a topological interpretation of structural validation for both objectivists and relativists. As will be seen, recent advances in the domain of fuzzy topology allow for a valuable metaphor of a relativistic attitude towards modelling and structural validation. Finally, we will discuss several general types of modelling errors that may occur and examine their repercussion on the natural topological spaces of objectivists and relativists. We end this paper with a formal, topological oriented definition of structural model validity for both objectivists and relativists. The paper is concluded with summarising the most important findings and giving a direction for future research.Model; Simulation; Theory; Scientists; Processes; Statistical analysis;

Model Checking Dynamic-Epistemic Spatial Logic

In this paper we focus on Dynamic Spatial Logic, the extension of Hennessy-Milner logic with the parallel operator. We develop a sound complete Hilbert-style axiomatic system for it comprehending the behavior of spatial operators in relation with dynamic/temporal ones. Underpining on a new congruence we define over the class of processes - the structural bisimulation - we prove the finite model property for this logic that provides the decidability for satisfiability, validity and model checking against process semantics. Eventualy we propose algorithms for validity, satisfiability and model checking

About the relations between Management Accounting Systems, Intellectual Capital and Performance

The present study is focused on the contribution of management accounting systems (MAS) in the development of intellectual capital (IC). Based on empirical evidence that supports the proposition that the value creation process is strongly associated to the level of IC, the study also examines the mediating effect of MAS on performance through their positive direct effect on IC. These relationships were consolidated into a model and empirically tested with data from 281 Portuguese firms using the Structural Equation Modeling (SEM). The findings show that six out of nine hypothesized relationships were supported by data with positive and significant causal links between MAS and the human and structural dimensions of IC. Results confirmed the conceptual validity of the circular model for the interactions among the three IC dimensions. Results also showed a positive and significant direct effect of structural capital on performance. Overall, the results confirmed the validity of the proposed model and contributed to the literature on the role of MAS in supporting the development of the I

Parental involvement in sport:psychometric development and empirical test of a theoretical model

The purposes of the present multistudy were to develop and provide initial construct validity for measures based on the model of parental involvement in sport (Study 1) and examine structural relationships among the constructs of the model (Study 2). In Study 1 (nparents = 342, nathletes = 223), a confirmatory factor analysis was used to verify the psychometric properties of the measures. Content and construct validity were evaluated, as well individual and composite reliability. Multi-group analysis with two independent samples provided evidence of factorial invariance. In Study 2 (nparents = 754, nathletes = 438), structural equation modeling analysis supported the hypothesised model in which athletes’ perceptions of parents’ behaviours mediated the relationship between parents’ reported behaviours and the athletes’ psychological variables conducive to their achievement in sport. The findings provide support for the parental involvement in sport model and demonstrate the role of perceptions of parents’ behaviours on young athletes’ cognitions in sport

Psychometric properties of the Chinese (Putonghua) version of the Oxford Cognitive Screen (OCS-P) in subacute poststroke patients without neglect

Background Oxford Cognitive Screen is designed for assessing cognitive functions of poststroke patients.This study was aimed to assess the psychometric properties of the Chinese (Putonghua) version of theOxford Cognitive Screen-Putonghua (OCS-P) for use among poststroke patientswithout neglect. Methods Expert reviewpanel evaluated content validity of theChinese-translated items. After pilot tested the translated items, the patients and healthy participants completed the OCS-P as well as theMontreal Cognitive Assessment (MoCA-ChiB) andGoldenberg’s test.Agroup of patients completedOCS-P for the second timewithin seven days.Data analyses included confirmatory factor analysis, item difficulty and item-total correlation, inter- and intrarater reliability, internal consistency, and between-group discrimination. Results One hundred patients and 120 younger ( = 60) or older ( = 60) healthy participants completed all the tests. Modifications were required for items in the “Picture Naming”, “Orientation”, and “Sentence Reading” subscales.Confirmatory factor analysis revealed a three-factor structure for theOCS-P subscales.The internal consistency coefficients for the three identified test dimensions were 0.30 to 0.52 (Cronbach’s alpha). Construct validity coefficients between the OCS-P and MoCA-ChiB subscales were 0.45 Conclusion This study generated satisfactory evidence on the content validity, substantive validity, construct validity, inter- and intrarater reliability, and known-group discrimination of theOCS-P.They support its application among poststroke patients who speak Putonghua. Future studies could review the existing five-dimension domains for improving its structural validity and internal consistency as well as generate evidence of the OCS-P for use among the poststroke patients with neglect.</p

Balance-of-payments-constrained growth in a multisectoral framework: a panel data investigation

This paper contributes to the literature on balance-of-payments-constrained growth by providing an innovative empirical evaluation of a disaggregated version of the so-called Thirlwall's Law derived from a Pasinettian multisectoral framework. After estimating sectoral elasticities of exports and imports for a considerable panel dataset of 90 countries over the period 1965-1999, we have performed two empirical exercises. First, we grouped countries together by income level and evaluated a multisectoral balance-of-payments-constrained growth model by analyzing prediction errors and mean absolute deviations. Second, we carried out a regression validity test on the results. Our main findings give support to the validity of the multisectoral version of Thirlwall's Law, providing therefore further understanding of the structural determinants of the uneven international development and guidance for the design of growth-enhancing national structural policies.balance-of-payments constraint; structural change; economic growth; macrodynamics

Community Policing and Intelligence-Led Policing: An Examination of Convergent or Discriminant Validity

Purpose Despite increased scholarly inquiry regarding intelligence-led policing (ILP) and popularity among law enforcement agencies around the globe, ambiguity remains regarding the conceptual foundation and appropriate measurement of ILP. Although most scholars agree that ILP is indeed a unique policing philosophy, there is less consensus regarding the relationship between ILP and the ever-present model of community-oriented policing (COP). Consequently, there is a clear need to study the empirical distinctions and overlaps in these policing philosophies as implemented by US law enforcement agencies. The paper aims to discuss these issues. Design/methodology/approach Data were gleaned from the 2007 LEMAS and 2009 NIJ Intelligence surveys. A total of 227 unique police agencies in the USA are included. A series of bivariate, exploratory factor analyses and structural models are used to determine discriminatory or convergent validity across COP and ILP constructs. Findings The goal was to answer the question: are these two policing philosophies are being implemented as separate and distinct strategies? Results of our exploratory and structural models indicate that COP and ILP loaded on unique latent constructs. This affirms the results of the bivariate correlations, and indicates that COP and ILP have discriminant measurement validity. In other words, COP and ILP are conceptually distinct, even when implemented in police departments across the USA. Implications of these findings and suggestions for future research are discussed. Originality/value This is the first study to empirically test the discriminant or convergent validity of COP and ILP

Similarity Structure Analysis and Structural Equation Modeling in Studying Latent Structures: An Application to the Attitudes towards Portuguese Language Questionnaire

Several international studies such as PISA and PILRS (Progress in International Reading Literacy Study), have stressed the importance of positive attitudes and behaviours as facilitators of individuals reading literacy during the school years and throughout their lives. Considering that there are not available instruments for assessing attitudes Towards Portuguese Language, it was proposed the development of the Attitudes towards Portuguese Language Questionnaire – ATPLQ (Questionário de Atitudes Face à Língua Portuguesa: QAFLP, Neto et al., 2011; Rebelo, 2012). The questionnaire has 22 Likert-type items, with four levels of response (Strongly Disagree, Disagree, Agree, Strongly Agree), spread, through exploratory factor analysis (EFA), over three attitudinal dimensions: Behavioural, Affective, and Motivational.In this study we aimed to analyse the ATPLQ’s latent structure with a pooled sample data of 1441 participants, applying similarity structure analysis (SSA) and confirmatory factor analysis of ordinal data (CFA). The SSA was carried out with Hudap in order to identify the structural properties of the questionnaire and to assess its adequacy in a Portuguese population. The CFA was carried out with LISREL in order to assure structural validity, i.e., accounting for factorial validity, but also for factors’ convergent and discriminant validity, and composite reliability. These psychometric features allowed the comparison of both the EFA derived model and the SSA derived model. We justify the selection of the SSA’s model, and we discuss the similarities between the results generated by SSA and LISREL procedures, highlighting their use in modeling constructs with ordinal indicators