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This work surveys the use of directed weighted graphs in conducting comparative static analyses. The paper discusses the implementation of a computer-aided process for building spreadsheet-based graph models for inter- and intra-regional financial flows. The graph-theoretic techniques are programmed to enable the interactive visualization and analysis of financial data using Wolfram technologies (i.e., Mathematica software v. 11.3 or later, Wolfram player v. 12 or later). The paper describes the workflow for several interactive visualizations applicable to financial networks. The author provides four programs, written in the Wolfram language, that customize input–output financial models by combining the Manipulate command with built-in Mathematica functions and functions of the IGraph package (IGraph/M). The study is a tutorial article for the generation of a suite of visual schemes that provide patterns, practices, and roadmaps of the financial markets across the globe. [ABSTRACT FROM AUTHOR]

From Cournot, Walras, and Pareto's research to what followed in the form of marginalist economics, chaos theory, agent-based modeling, game theory, and econophysics, the interpretation and analysis of economic systems have been carried out using a broad range of higher mathematics methods. The evolution of mathematical economics is associated with the most productive and influential authors, sources, and countries, as well as the identification of interactions between the authors and research topics. Bibliometric analysis provides journal-, author-, document-, and country-level metrics. In the present study, a bibliometric overview of mathematical economics came from a screening performed in September 2023, covering the timespan 1898–2023. About 6477 documents on mathematical economics were retrieved and extracted from the Scopus academic database for analysis. The Bibliometrix package in the statistical programming language R was employed to perform a bibliometric analysis of scientific literature and citation data indexed in the Scopus database. VOSviewer (version 1.6.19) was used for the visualization of similarities using several bibliometric techniques, including bibliographic coupling, co-citation, and co-occurrence of keywords. The analysis traced the most influential papers, keywords, countries, and journals among high-quality studies in mathematical economics. [ABSTRACT FROM AUTHOR]

This paper aims to work towards a factual framework to substantiate the linkage between corporate social responsibility (CSR) reporting and economic activity and between CSR reporting and CO2 pollution, continent-wide. The document summarizes the conclusions of the dynamic analysis of CSR reports and the correlation analysis between CSR reports and economic—environmental variables, always using evidence from continent-level data. We draw on growth—environmental data and CSR reports from 1999 to 2017 to perform an analysis that quantifies the direction, the strength and the nature of the dependence structure between the two variables. Continents' position according to their CSR reporting performance, CSR report trends over time, comparative schemes among continents, compose a global view on continents' differentiation on CSR practices and strategies. Overall, the paper contributes to the understanding of how the CSR policies have been integrated and evolved worldwide. [ABSTRACT FROM AUTHOR]

In this work, we map and measure the interdependencies that exist in green bond markets, relying on yearly proceeds allocation data reported in Tolliver et al. (Environ Res Lett 14:064009, 2019). We focus on transactions from 53 organizations to projects and assets throughout 96 countries from 2006 to 2017 and we build the network of relationships between market participants. Network analysis is a powerful tool to examine the international flows of green bonds and countries' or regions' positions in the international green bond transfer network. Such analysis allows for studying the input–output relationship among countries and among regions in a structural way and not in isolation, i.e., taking into account the strong interdependence among all participants. The network is directed and the arrows that represent the edges are oriented from the allocator to the recipient country/region. We employ an established methodology, based on various measures of network centrality, to identify the most significant members which we consider the "backbone" of the market. The influence of countries is measured in terms of their green bonds exports and imports volume and frequency, under the "too-connected-to-fail" and "too-big-to fail" concepts (criteria). A more elegant approach is to redefine systemic importance of financial infrastructures in terms of the importance of their neighbors. The analysis shows a highly influential group of countries, with Germany, Sweden, Luxembourg, the Netherlands, France, the USA, United Kingdom being constantly in the top ten central economies with a leading role in the green bond market. Finally, we study how these graph metrics evolve across the years of the study period. [ABSTRACT FROM AUTHOR]

A Semantic Web-based software tool/application called "Web-FCM" is designed and implemented using the well-established Artificial Intelligence technique of Fuzzy Cognitive Maps (FCMs). The main purpose of the special issue is to feature the computational practice of green policy performance measurement. Understanding sustainable development linkages and achieving the required policy trade-offs across the environmental, economic, and social spheres requires a wide range of tools and methodologies. [Extracted from the article]

Effective environmental policies have to be based on robust information taking into consideration the existing trends. The objective of this paper is to facilitate data-driven decisions. Specifically we aim at policies that are built on officially reported emissions data making use of intuitive tools and interfaces to guide European air quality strategies with completeness and consistency. Transboundary (or cross-border) air pollution is a two-sided problem involving a polluter and a pollutee. The visualizations we have created allow a user to conceive the transboundary air pollution scheme from either the polluters' or pollutees' perspective. Based on the European Monitoring and Evaluation Program (EMEP) source-receptor matrices from 2003 to 2014, we develop comprehensive pollution monitoring systems. Our systems are created in visualization software in order to bring out the status, attributes and dynamics of transboundary air pollution. Our monitoring applications consist of different visualization modules. All of these modules carry their own information, which can be used separately or together to serve specific visualization tasks: either the polluters' responsibility or the pollutees' vulnerability. Several interactive interventions are integrated into each module to achieve particular visualization goals. Controls are added for the number of polluters, year of study, pollution level and geographical region within the extended EMEP area. [ABSTRACT FROM AUTHOR]

This study proposes a new method of graph computing for environmental economics. We apply a weighted graph model that reproduces the structure of SOx emission-deposition tables. Our data apply scientific and technical data on emissions, atmospheric processes, and effects on the environment of sulfur oxides from the European Monitoring and Evaluation Program of the long-range transmission of air pollutants in Europe. Our graph metrics consider both the activity and the amount of pollution for each polluter. The results show the contribution of oxidized sulfur emitted from one country and deposited to another. The most influential node of the country-to-country blame network is tracked using indicators of centrality. Exploring options and metrics for ranking the blame for SOx pollutants, we depict the degree of the responsibility for SOx depositions in EU countries graphically. [ABSTRACT FROM AUTHOR]

Our contribution in this work is to set the directions for specialized econometric computations in a free computer algebra system, Xcas. We focus on the programming of a routine dedicated to correlation criteria for multiple regression models. We program several operations for detecting and evaluating collinearity by applying the diagnostic techniques of linear regression analysis. In order to illustrate the computational performance of our Xcas codes, we repeat most of the analysis carried out in widely used commercial software, along with some extra statistics. Xcas could constitute a supplemental tool in a collinear data study. Its use is proposed complementary to established econometric software or as substitute software. [ABSTRACT FROM AUTHOR]

We present classical multi-regional multi-sectoral input–output trade structures from the perspective of networks. Unlike existing approaches by which dynamic changes in structures are studied, here, emphasis is given on recovering the stable structure architecture of interrelations in the input–output model. By self-explanatory visual outputs we display the connectivity patterns, interactions of the trading partners, the number of trade linkages per trader and the density of interrelations of the network. Our network analysis traces causal relationships, feedback loops and examines certain global structural properties. The whole computational approach is implemented in Mathematica. Our programming style allows for the creation of iterative schemes explaining the the linkage development among sectors, the influence of regions and sectors system-wise, aspects of the nature of trade and, the evolution of spatial trading/production cycles in growing trading networks. [ABSTRACT FROM AUTHOR]

This paper introduces a visual framework in the environment of a computer algebra system for displaying interregional trading patterns in multi-region, multi-activity economies. Interregional input-output tables illustrate spatial and economic interdependencies within interregional trade and are considered a key component in input-output modeling. The study and analysis of the interregional trade flows in interregional economic activities often reveal interregional and inter-activity linkages, referred to as 'feedback loops' and/or spatial production cycles in interregional level. Trade theory considering feedback loops is a relatively new approach to the detailed analysis of vertical specialization of trade flows. This approach leads to the decomposition of global trade into feedback loops. Given the analysis of interregional inter-activity feedback loops based on the trade flows data, interregional input-output tables and associated trading patterns can be depicted using programmed functions in MATHEMATICA. Our programmed functions create static and dynamic images presenting the structure and the intensity of feedback loops connecting the regions and the activities of an economy. The generated visual schemes succeed to picture the multilateral trade connections between all regions. The programming codes along with their application in examples from the relevant literature are our methodological contribution in the visualization of trading tables. [ABSTRACT FROM AUTHOR]

The study of interactions between the economy and the environment has always been an interesting subject. Apart from static input-output (IO) models, environmentally extended IO analysis has resulted in dynamic IO models as well. Dynamic models are built of differential equations and, in the case of discrete models with the help of difference equations. The dynamic approach requires advanced mathematical skills especially in cases where the stability of the system under study is considered. In this paper we state some applied environmental models in discrete time based on dynamic IO analysis and we propose a computational approach in computer algebra system environments that investigates the extent and the nature of their stability. The computer codes are fully presented and can be reproduced as they are in computational-based research practice and education. [ABSTRACT FROM AUTHOR]

This paper introduces a visual framework in computational environment for displaying multi-region, multi-sector classical models, associated with authors such Isard, Chenery, Moses, Leontief, Riefler and Tiebout. Based on the quantity and nature of trade data of each model, different conditions are imposed upon the matrix of trade coefficients $$T$$ which result in various matrix partitioning schemes. Matrix $$T$$ illustrates the interactions among interregional and intersectoral economic activities and is considered a key component in input-output modeling. Using MATHEMATICA as software tool we introduce a method to construct and present matrix $$T$$ both graphically, with static and dynamic images, and analytically. The output produced enables understanding and/or teaching theoretical trade hypotheses. Furthermore, our computational approach produces random, structured matrices of trade coefficients, which makes possible infinite computer experiments with interregional input-output models of any size, without typing in input. The computer codes are fully presented and can be reproduced as they are in computational-based research practice and education. [ABSTRACT FROM AUTHOR]

Examining the identification problem in the case of a linear econometric model can be a tedious task. The rank and order conditions are commonly used in identification for simultaneous equations models. The order condition of identifiability is an easy condition to compute, though maybe difficult to remember. The application of the rank condition, due to its complicated definition and its computational demands, is time consuming and contains a high risk for errors. Furthermore, possible miscalculations could lead to wrong identification results, which cannot be revealed by other indications. Thus, a safe way to test identification criteria is to make use of computer software. Specialized econometric software can off-load some of the requested computations but the procedure of formation and verification of the identification criteria are still up to the user. In our identification study we use the program editor of a free computer algebra system, Xcas. We present a routine that tests various identification conditions and classifies the equations under study as «under-identified», «just-identified», «over-identified »and «unidentified», in just one entry. [ABSTRACT FROM AUTHOR]

Purpose - Greek social security system has a provision, under which women who have children are entitled to exit the labour force and claim pension benefits after completing 20 years of work and at a fully productive age. The critical issue arising from this regime is that it seems that mothers are rewarded for their nature of being able to give birth to children, which is unfair for the rest of working people. This paper aims to address these issues. Design/methodology/approach - The reward of maternity should be given at the proper time, i.e. by subsidizing mothers to stay at home and breeding their children. For this purpose we set up a cost-benefit analysis in an overlapping generation model in order to compare the present provision with an alternative, under which mothers are subsidized and abstain from the labour market for 15 years. However, this policy could be applied to either gender. Findings - In the model we develop (as alternative) we show that this kind of provision, under certain parameters' values could be to the benefit of the social security system in pure financial terms, beyond the other positive qualitative externalities for the society. Practical/implications - This alternative policy could be proved more efficient in financial and economic terms for the social security system, but it could also influence family programming and increase birth rate. Originality/value - The most valuable result is that children breeding and the occupation of one parent with this task are not deterministically inefficient, or waste of resources, for the economy and the social security system, as many economists (and other social scientists) insist. And on the other hand, breeding of children by their parents is precious for the society since it strengthens family and, through that, social bonds. [ABSTRACT FROM AUTHOR]

Deals with a resonant eigenvalue problem for a hemivariational inequality, arising in the study of a mechanical problem on the buckling of an adhesively supported beam. Background on the mechanical problem; Description of the approach used.

The present paper deals with an eigenvalue problem for a hemivariational inequality, arising in the study of a mechanical problem: the buckling of a von Kármán plate adhesively connected to a rigid support with delamination effects. For this eigenvalue problem an existence result is obtained by applying a critical point method suitable for nonconvex nonsmooth functions. Further, a result concerning the multiplicity of solutions is proved. The mechanical interpretation of these results is briefly discussed. [ABSTRACT FROM AUTHOR]

Simple Summary: Common sole (Solea solea) is an important species for the aquaculture industry. Defects in pigmentation of the species are very common in farmed conditions. Differences in gene expression between normally pigmented juveniles and those that present both sides full pigmented, ocular and blind, were investigated. Differentially expressed transcripts were functionally annotated, and gene ontology was carried out. The results indicated that ambicolorated juveniles showed a significant upregulation of genes involved in the signal transmission at the synaptic level and regulation of ion channels, affecting the plasticity and the development of the synapses, as well as the transmission of signals or ions through channels. In farmed flatfish, such as common sole, color disturbances are common. Dyschromia is a general term that includes the color defects on the blind and ocular sides of the fish. The purpose was to examine the difference in gene expression between normal pigmented and juveniles who present ambicoloration. The analysis was carried out with next-generation sequencing techniques and de novo assembly of the transcriptome. Transcripts that showed significant differences (FDR < 0.05) in the expression between the two groups, were related to those of zebrafish (Danio rerio), functionally identified, and classified into categories of the gene ontology. The results revealed that ambicolorated juveniles exhibit a divergent function, mainly of the central nervous system at the synaptic level, as well as the ionic channels. The close association of chromophore cells with the growth of nerve cells and the nervous system was recorded. The pathway, glutamate binding–activation of AMPA and NMDA receptors–long-term stimulation of postsynaptic potential–LTP (long term potentiation)–plasticity of synapses, appears to be affected. In addition, the development of synapses also seems to be affected by the interaction of the LGI (leucine-rich glioma inactivated) protein family with the ADAM (a disintegrin and metalloprotease) ones. [ABSTRACT FROM AUTHOR]