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A Discrete Duality Finite Volume Method For Coupling Darcy and Stokes Equations

Abstract

We present a general finite volume method to solve a coupled Stokes-Darcy problem, we propose two domains corresponding to fluid region and porous region with a physical intersection. At the contact interface between the fluid region and the porous media we impose two conditions; the first one is the normal continuity of the velocity and the second one is the continuity of the pressure. Furthermore, due to the lack of information about both the velocity and the pressure on the interface, we will use Schwarz domain decomposition. In Darcy equations, the tensor of permeability will be considered as variable, since it depends on both the properties of the porous medium and the viscosity of the fluid. Numerical examples are presented to demonstrate the efficiency of the proposed method.

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Fixed point theorem satisfying cyclical conditions in b-Menger spaces

Abstract

In this work, we prove a fixed point theorem for mapping with cyclical conditions using comparison function in b-Menger spaces. We support our results by an example.

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A Modified Fractional Differential Love Model

Abstract

A modified system of nonlinear fractional-order differential equations become used to classify humans of various personalities and different Impact Factors of Memory (IFM); with unique set of model parameters. The model was used to interpret and predict the functions of the union of various people with external circumstance(s) and adapted to neighborhood environment in which the statistics collections were achieved to analyze numerous measures affecting marriages, unique challenges in marriage and associated occasions were investigated through the use of questionnaire. Data had been analyzed and the outcomes have been carried out as parameters to validate the model. Adams Predictor-Corrector Method was used to test the chaoticity of the system and it was confirmed via numerical simulations.

Numerical simulation outcomes had been presented to reveal the effectiveness of the model and the accuracy of the statements established. The mathematical information implied by the model unveil an underlying mechanism which can give an explanation for couple disruption in relationships that were initially deliberated to remain all the time. Despite the terrible aspects of relationships, some human beings were still satisfied in their intimate members of the family. The study was addressed on a field survey (use of questionnaires) and with the aid of interrogating the members one on one. A feasible path for future work is the choice to attain balance through modelling and to validate the results with the aid of numerical simulations.

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Achieving Portfolio Diversification through Cryptocurrencies in European Markets

Abstract

Background: Cryptocurrencies represent a specific technological innovation in financial markets that keeps getting more and more popular among investors around the world. Given the specific characteristics of the cryptocurrencies, this paper examines the possibility of their use as a diversification instrument.

Objectives: This paper examines the direction and strength of the relationship between the selected cryptocurrencies and important financial indicators on the European Union market. Since cryptocurrencies are a novelty in the financial system, the empirical literature in this area is rather scarce.

Methods/Approach: In order to assess diversification properties of cryptocurrencies for European traders, a comprehensive econometric analysis was carried out. The first part of the analysis refers to the estimation of the multivariate Generalized Autoregressive Conditional Heteroskedasticity (GARCH) model, whereas the second part focuses on wavelet transforms.

Results: Bitcoin and Ripple proved as a possible diversification instrument on most of the observed European markets since corresponding coefficients of unconditional correlation are negative.

Conclusions: The relationship between the value of the cryptocurrencies and selected indices is generally very weak and slightly negative, indicating that some cryptocurrencies can serve as a means of diversification. However, investors need to take into account the extreme volatility, exhibited in all existing cryptocurrencies.

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Analysis of Happiness in EU Countries Using the Multi-Model Classification based on Models of Symbolic Data

Abstract

The results of happiness analysis are presented in the form of a World Happiness Report that covers 156 countries and 17 different indicators. In the article model-based clustering ensemble is built to determine what selected European countries have similar patterns of happiness. The results are analyzed using multidimensional scaling and a decision tree to find out what factors determine cluster memberships. In the empirical part, three clusters were detected The first contains countries: Austria, Denmark, Finland, Germany, Ireland, Luxembourg, the Netherlands, Norway, Sweden, Switzerland and the United Kingdom. They have the highest values for all the variables, except the negative affect. The second cluster contains seven countries: Bulgaria, Estonia, Hungary, Lithuania, Poland, Romania and Slovakia. This cluster is also the most homogeneous one. The third cluster contains eight countries: Cyprus, the Czech Republic, France, Greece, Italy, Portugal, Slovenia and Spain.

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Analysis of Higher Education Indicators Coherency in Central and Eastern Europe

Abstract

Background: Higher education has the main role in generating innovative activity in knowledge-based economies. Therefore, the efficiency of the higher education sector reflects the alignment of the higher education policy with government expenditure. However, countries in Central and Eastern Europe (CEE region) have been struggling with national budget optimisation, which can cause fiscal stress and thus affect the efficiency of higher education.

Objectives: The main objective is to examine mutual interaction of higher education indicators, through formulating financial models that connect performance and financial indicators.

Methods/Approach: A total of 4 higher education indicators were analysed and observed in the time period of 10 years in selected CEE countries. The statistical analysis was based on panel data models.

Results: The main result of the paper is the analysis of coherency of selected higher education indicators in selected CEE countries in order to establish functional links between government expenditure and efficiency through formulating financial models.

Conclusions: Formulated financial models can predict the behaviour of selected performance indicators, depending on financial indicators. Therefore, the obtained models can contribute to the efficient allocation of funds and comprehensive macro-level decision making assessments in higher education policy reforms.

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Assessing Tourist Revisit Intention through the Sports and Recreational Services Offered

Abstract

Background: Sports and recreational tourism are forms of tourism that imply active involvement of tourists in various sports activities during their vacation, and it can be said that the main motive of such a vacation is a sport.

Objectives: This research aimed to determine the relationship between sports and recreational activities and tourist satisfaction based on the questionnaire related to the behaviour and satisfaction of tourists during their stay in Montenegro.

Methods/Approach: Regression analysis has been conducted in order to assess the interaction between sport-recreational activities and previous experience in Montenegro, and their effect on tourist revisit intention.

Results: Empirical results demonstrate the influence of sports and recreational services on tourist satisfaction measured by tourists’ revisit intentions. Distinguishing between sports, and health, spa and wellness facilities and services, the findings indicate that health, spa, and wellness facilities and services have a higher impact on revisit intention than sports activities. In addition, the interaction effect between different sports and recreational activities and previous experience in Montenegro did not provide a more amplified effect on tourist satisfaction.

Conclusions: Establishing closer links between workers who provide sports services and those providing other tourist services is one of the main challenges in the future of the development of sports tourism in Montenegro, as one of the most critical aspects that can provide tourist satisfaction. The data study can be used for more efficient and effective decision making and strategy development of sports and recreational activities in the tourism industry.

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Determinants of Tax Morale in Croatia: an Ordered Logit Model

Abstract

Background: A lower tax morality leads to an increased readiness to become active in the unofficial economy and causes the lack of public revenues.

Objectives: The aim of this paper is to investigate determinants that shape tax morale of Croatian citizens.

Methods/Approach: An ordered logit model is employed to evaluate which determinants shape tax morale of Croatian citizens. Data for the research were collected from 2,000 face-to-face interviews conducted in Croatia in late 2015.

Results: The descriptive analysis illustrates that 52 percent of respondents reported a high level of tax morale, 26 percent of respondents have a low tax morale, while 8 and 14 percent have a mid-low and a mid-high tax morale, respectively. The ordered logit analysis revealed that gender, age, financial situation, region, and participation in the unofficial economy have an impact on the tax morale.

Conclusions: Besides socio-demographic, socio-economic, and spatial determinants, a great number of sanctions for participation in informal activities also shapes tax morale of the Croatian citizens. More precisely, marginal effects show that those perceiving the expected sanctions as “normal tax or social security contributions due, plus a fine or a prison sentence” have by 6.3 percentage points higher probability of reporting the highest tax morale than others.

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Editorial for the special issue: “Advances and Trends in Post-transition Countries: Statistical Modelling Approach”

Abstract

This special issue of Business Systems Research is highlights recent advances and trends in post-transition countries, taking into account statistical modelling approach. Nine papers that have been selected for this special issue present improvements and new techniques (methodology) in statistical modelling and their use in various aspects of development in post-transition countries

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Employers’ Perceptions of Business and Economics Graduates’ Competencies in Croatia

Abstract

Background: The issue of graduates’ competencies is not a new one, but was brought back into the spotlight after the 2007-2008 Global Financial Crisis and the ensuing disturbances in the labour market. These disturbances were manifested through an increased unemployment rate, with a significant share of highly educated people.

Objectives: This paper provides an insight into employers’ assessment of the importance and sufficiency of the competencies acquired by business and economics university bachelor graduates in Croatia.

Methods/Approach: The methodology applied in this research includes the importance-performance analysis (IPA) that provides a two-dimensional importance-satisfaction grid. Data for the IPA analysis were collected by the structured questionnaire.

Results: Results indicated that employers are satisfied with specific competencies (business and economic) and that the emphasis of business and economics higher education institutions (HEI) should be placed on generic competencies.

Conclusions: Findings imply that mobility of highly educated people could be caused by the level and quality of specific competencies of bachelors with a degree from Croatian economics higher education institutions. Additionally, the conclusion of the conducted study indicates a need for implementation of student-oriented teaching methods, the introduction of obligatory internship, and introduction of courses oriented towards the development of generic competencies.

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