No 4/2015, December
Analysis of the Behaviour of Prices of Major Staple Foods in West Africa: A Case Study of Nigeria
The study analyzed the price behavior of major staple foods in West Africa taking Nigeria as a case study (1966 – 2011). It described the trend of the major staple food prices and examined the linear relationship and interdependence of the major staple food prices in Nigeria. Secondary data were used for this study. The sources were; Food and Agriculture Organization (FAO), and National Bureau of Statistics (NBS). These data were transformed from their nominal value to real value and analyzed using descriptive statistics, unit root test, Pearson correlation coefficient, granger-causality test and structural equation model. The study revealed that the prices of most of the major staple foods were at the maximum value between 1991 and 1993 while their prices were at the minimum value between 1978 and 1983. The study observed that the price of cowpea is most volatile seconded by maize. The results of the unit root test showed that all the variables studied were stationary. The prices of the major staple foods were linearly correlated; some were positively correlated while some were negatively correlated. Granger-causality test on the major staple foods prices showed that the prices of most staple foods were unidirectional while only few were bi-directional. The study further revealed that the prices of staple foods were interdependent. The study recommends political stability in the country as the major staple food prices reached maximum level during the period of 1993 presidential election crisis.
Staple food, prices, behavior, maize, rice, yams, cowpea, sorghum and cassava.
Ayinde, O. E., Ilori, T. E., Ayinde, K. and Babatunde, R. O. (2015) “Analysis of the Behaviour of Prices of Major Staple Foods in West Africa: A Case Study of Nigeria”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 3 - 17. ISSN 1804-1930.DOI
Developing the Metodology to Form Integrated Reporting of Agroholdings in the Russian Federation
The article represents the efficient methodological principles on preparing the integrated reporting, as well as the scheme of the agroholding coherently integrated registration system based on the analysis of the concept and methodology in the field of the integrated reporting; it specifies "growth points" of the methodology development and best practical applications of the concept of uniform reporting on a global scale. The authors propose the developed by them "road map" on the organization process forming the integrated reports, and define the guidelines on improving the process of preparing and quality of the integrated reporting for the medium-term period.
Methodology of integrated reporting; uniform accounting system; agro-industrial holdings; organization of integrated accounting; road map; guidelines on methodology development.
Balashova, N. N., Šilerová and E., Melikhov, V. A. (2015) “Developing the metodology to form integrated reporting of agroholdings in the Russian Federation”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 19 - 29, ISSN 1804-1930.DOI
Augmented Reality As a Working Aid for Intellectually Disabled Persons For Work in Horticulture
The main focus of this article is to verify experimentally the possibility of using Augmented Reality as a platform for display educational materials in the field of horticulture in the real world for people with intellectual disabilities. Experimental verification was attended by eight people with varying levels of mental disability. The educational material was presented to the research participants in the form of a video, which was accessible via Wikitude platform based on the specific GPS coordinates. To find and display the content, participants used iPad2 and Android tablet devices. Despite the great potential of Augmented Reality technology, on the basis of undertaken studies it is still not possible to recommend this type of education for people with intellectual disabilities.
Accessibility, Augmented Reality, intellectual disability, horticulture.
Benda, P., Ulman, M. and Šmejkalová, M. (2015) “Augmented Reality As a Working Aid for Intellectually Disabled Persons for Work in Horticulture”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 31 - 37, ISSN 1804-1930. DOI
Market Power in the European Dairy Industry
The paper presents an analysis of market power in the output milk-processing market. In particular, the paper identifies market failures in the output milk-processing market in 24 EU member states. The analysis is based on a mark-up model and the application of stochastic frontier methodology. The results show that market failures are pronounced on the EU output milk-processing market. However, the abuse of oligopoly market power is not large on average, despite the fact that we can find significant differences among the countries. The mark-up distribution is skewed toward lower values. That is, the majority of companies are characterized by only a small or almost no degree of market power; however, there are companies (about 10 %) with considerably high oligopoly market power.
Milk, market power, oligopoly, SFA, European Union.
Čechura, L., Žáková Kroupová and Z., Hockmann, H. (2015) “Market Power in the European Dairy Industry”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 39 - 47, ISSN 1804-1930. DOI
Why Do Agricultural Producers Exhibit at Bread Basket?
A literature survey proved that trade shows are important marketing tools, enabling sellers to present and test new products, to monitor their competitors, and to establish personal contacts with customers. The paper extends the current research of trade shows by analyzing exhibitors ́ motives for exhibiting. The research is conducted for a traditional international agricultural fair - Bread Basket. Exhibitors, including animal production exhibitors, crop production exhibitors and agriculture technology exhibitors, were offered a list of potential motives for exhibiting and were asked to indicate their agreement (disagreement) on a 5-point Likert scale. Subsequently, a factor analysis revealed four key factors for exhibiting, including searching for information and company development, product development, focus on company surroundings and new market possibilities. Finally, exhibitors were surveyed again in order to choose one of these factors to be the most important one for exhibiting. Logistic regression revealed how the specific variables (NACE classification, year of establishment and frequency of exhibiting) influence the selected factors.
Milk, market power, oligopoly, SFA, European Union.
Havlíková, M. and Kolářová, A. (2015) “Why Do Agricultural Producers Exhibit at Bread Basket?”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 49 - 56, ISSN 1804-1930. DOI
E-trade with Direct Lending and Normalized Money
The article presents the advanced technology of the normalized commodity-money relations. The technology is considered as updating the model of the normalized economic mechanism. The core of this technology is the e-trade with direct lending where deferred portion of the payment is documented as the buyer's debt to the seller (not to the bank!). The technology of e-trade with direct lending provides the possibility of early repayment of debt amounts to the sellers of priority goods. This repayment is fulfilled by the debt department of the state central bank. Rules of emission of debt amounts are presented in the advanced model of normalized money. The important innovation in normalized e-trade is the rule of obligatory state online certification of transactions.
E-trade with direct lending, normalized money, system of property statuses, normalized economic mechanism, e-service, normalized e-banking.
Ilyin, A. V. and Ilyin, V. D. (2015) “E-trade with Direct Lending and Normalized Money”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 57 - 64, ISSN 1804-1930. DOI
Geospatial Data Infrastructure Components Deployed for LTER -Europe Researchers’ Community
Assessing the status and trends of the environment requires the collection, management and publication of spatially referred observations. Since many years, Long-Term Ecological Research sites in Europe collect ecological data, resulting in long-term data series. Nowadays, advanced software tools can enable discovering, accessing, and distributing collected data in a user friendly way. Based on Open Geospatial Consortium (OGC) standards, Web based Geographic Information System allows access to interoperable distributed repositories of observations. The present paper gives an overview of the methods and solutions proposed and tested in the LIFE+ project EnvEurope for the community of researchers of the Long-Term Ecosystem Research (LTER) Network in Europe. These solutions consist in a straightforward online environment for metadata management and discovery, shaped on the ecological community and its practices; components of a Spatial Data Infrastructure including both a network of repositories deploying observations via OGC SOS (Sensor Observation Service) services and Web user interfaces to access and visualize them. The success of the presented approach is linked to the development and availability of easy to define, ready to use tools, enabling site managers to create their own repositories and services.
Geospatial data infrastructure (GDI); metadata; observations; LTER Network; DEIMS; INSPIRE; Sensor Observation Service (SOS).
Kliment, T., Carrara, P. and Oggioni, A. (2015) “Geospatial Data Infrastructure Components Deployed for LTER-Europe Researchers’ Community”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 65 - 78, ISSN 1804-1930. DOI
Factors Influencing Career Success of Employees in Agribusiness
Effective HR management in the agribusiness industry can succeed in many ways. Our paper focuses to career success in the agribusiness, respectively to one of the most important human resource management tools. Applying decision-making methods using best practices in IT is cost-effective in more areas. Processing and sorting quantitative data was done using programs Statistica 10, Excel 2010. Furthermore, concerning the statistical hypothesis testing there were used modules Analysis of variance and t-test. Last but not least, there were used decision-making algorithms and corresponding software tools in support of identifying the types of suitable models of career decision-making processes.
The first part of this article concentrates on the theoretical background. The second part evaluates the results of a quantitative survey carried out for this research.
The research was conducted on a representative sample of agro-business companies, which were categorized according to EU recommendations. Representativeness of respondents’ selection was achieved by the randomization of the responder sample. This sample contained information from 226 employees of the agro-business sector.
The main aim of the paper is to evaluate the correlation between organization size and employee career success. A further aim is to identify the factors involved in career success. The outcomes of the questionnaire data were analyzed using descriptive and multidimensional statistical tools, based on Statistica 10 and Excel 2010 programs, supported by analysis of scatter variance and t-test for testing hypotheses. The results confirm three factors for career success: the first is a subjective criterion, namely career satisfaction. The others are objective factors – the occupational status, and income change. With reference to these three factors it was confirmed that the size of a company has an impact on career success. It was shown that, overall, employees are happy to work with their co-workers and that they are interested in their job. They were least satisfied with the leadership.
Purposeful combination of functionalities of IT tools with standard procedures questionnaire survey we came to the logical sequences of strategies for career decisions during the design a survey questionnaire and also in the synthesis of knowledge to the final variant.
The results further confirm that as the size of an organization increase, the number of employees who achieve a higher salary also increases. Thus, it is recommended that large organizations should utilize extrinsic career success factors, which are related to formal career programs and career plans. The next part of the research after the factor analysis (which provided us basic understanding of the significant factors to career success), was to perform more advanced methods such as Simplex Lattice Design (SLD) by adding two information technology factors (C - IT competence, D – Rate of IT utilization) to the current design.
Information technology, simplex lattice design, IT competence, rate of IT utilization, career success.
Macák, T., Štůsek, J. and Venclová, K. (2015) “Factors Influencing Career Success of Employees”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 79 - 89, ISSN 1804-1930. DOI
Efficiency of Production Factors and Financial Performance of Agricultural Enterprises
This article deals with the relationship between efficiency of use of the production factors in agricultural enterprises in Czech Republic and their financial performance. The aim of the article is to define common economic features of agricultural enterprises which labour productivity has been growing for a long time and, at the same time; they have been increasing value of their fixed assets (investing). The analysis was focused on 1098 agricultural enterprises classified according to the European Commission as micro, small and medium enterprises. The analysis showed that above-average agricultural enterprises (high growth of labour productivity and fixed assets), regardless of their size, have higher profitability indicators, higher indebtedness and lower quick ratio. Summarizing the results of the analysis of individual size classes, it can be said that the smaller size class, the bigger difference.
Labour productivity, fixed assets, agriculture, enterprises.
Novotná, M. and Volek, T. (2015) “Efficiency of Production Factors and Financial Performance of Agricultural Enterprises”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 91 - 99, ISSN 1804-1930. DOI
Italian Trade Specialization: Persistence and Change in Regional Agri-Food Production
The Italian agri-food sector has traditionally been one of the strongest in the national socio-economic system. In the last ten years, commercial exchange trends have shown growing openness towards foreign countries and in particular to European Union (EU) countries. Both the primary sector and food industry are strongly influenced by their territorial location so much so that several authors have highlighted territorial specialisation and its effects on that territory’s features also considering the contribution of the Italian Regions. The following work will analyse the patterns of agri-food specialisation in the Italian Regions. In particular, the Lafay Index will be used to evaluate competitive advantage at a Regional level.
Agricultural trade. Lafay Index. Comparative advantage. Regional specialization.
Platania, M., Rapisarda, P. and Rizzo, M. (2015) “Italian Trade Specialization: Persistence and Change in Regional Agri-Food Production”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 101 - 109, ISSN 1804-1930. DOI
Evaluation of the Effect of Subsidies on the Production Capability of Land in Selected Regions of the Czech Republic
A decline in the production capability of land affects the creation of farmers’ revenues, the effective utilization of agricultural land, its qualitative and quantitative degradation, as well as the competitiveness of Czech agriculture. The results of the IAEI Prague research show that the annual economic loss due to a decline in the quality of land in the Czech Republic within the analyzed period of the years 2009-2012 is approximately CZK 385 mil. (MoA, 2012a). The aim of the article is to evaluate the potential connections between the change in the quality of land and selected subsidies that should primarily be affecting the effective utilization of agricultural land and the continual sustainability of its production capability. In the research, the methods of correlation and comparison were used. The relationship between the amount of paid subsidies (SAPS+TNA, AEM, LFA) and after changing the production ability of soils (difference GARE) was not confirmed. A statistically significant relationship was found only in the subsidies NATURE 2000.
Agricultural land fund, Bonited Soil-Ecological Units /BSEU/, soil degradation, sustainable agriculture, Rural Development Program, greening, public goods.
Pletichová, D. and Gebeltová, Z. (2015) “Evaluation of the Effect of Subsidies on the Production Capability of Land in Selected Regions of the Czech Republic”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 111 - 122, ISSN 1804-1930. DOI
Value Proposition Canvas: Identification of Pains, Gains and Customer Jobs at Farmers' Markets
The goal of the research is to identify the factors of business model that form Value Proposition of farmers' market customers in the areas of (1) Products/Services, (2) Gain Creators and (3) Pain Relievers. The examined factor areas are based on the creation of a Value Proposition Canvas. Primary data were acquired through the method of questionnaire survey with 217 customers shopping at the farmer's market. The questionnaire was distributed in person. The most important Customer Jobs are identified as stocking up on fresh and healthy food and feeling good about the purchases; the most important Gain Creators are fresh and healthy food and the most important Pains are higher prices and inconvenient opening hours. Its results are five general recommendations for market sellers and organizers. It was also found that farmers' market customers made personal benefits a greater priority, much more than factors with a wider social scope.
Business model, value proposition canvas, customer's value, farmers' markets, fresh food, agribusiness.
Pokorná, J., Pilař, L., T. Balcarová, T. and Sergeeva, I. (2015) “Value Proposition Canvas: Identification of Pains, Gains and Customer Jobs at Farmers‘ Markets”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 123 - 130, ISSN 1804-1930. DOI
EU Quota Sugar Market Concentration – the Main Drivers of EU Sugar Market
The European sugar market is changing its character. During the last two decades its concentration changed and individual countries and companies have been preparing themselves for the end of sugar production quotas system. The level of competition within the EU sugar market is accelerating. Many companies already left the EU market or significantly reduced their production capacities. The main task of this material is to analyse the EU sugar market and especially sugar quotas character and to specify the current EU sugar production structures existing under the sugar quotas system. The paper is also identifying individual drivers/actors operating under the sugar quota system. The idea is to identify the level of EU sugar market concentration through the Herfindahl-Hirschman Index (HHI). The results coming from the analyses provides the overview of very specific character of the European sugar production quota system. However the market is operated by many companies and alliances, its production capacity are extremely concentrated. The majority of sugar plants are located in Germany, France, Poland and the majority of sugar quotas are controlled by companies headquartered in Germany, France, the Netherlands and the United Kingdom. In nowadays - the sugar quota system in the European Union is operated/controlled by only a few very powerful operators: Südzucker, Nordzucker, Tereos, ABF, Pfeifer & Langen, Royal Cosun and Cristal Union. This paper was supported by the Grant Agency at the Faculty of Economics and Management, Czech University of Life Sciences Prague: The selected aspects of economy sanctions and their impact on mutual trade between EU and Russia [nr. 20151031].
Sugar production, sugar quota system, quota distribution, sugar market, EU market.
Řezbová, H. Maitah, M. and Sergienko, O. I. (2015) “EU Quota Sugar Market Concentration – the Main Drivers of EU Sugar Market”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 131 - 142, ISSN 1804-1930. DOI
Mitigation of Social Exclusion in Regions and Rural Areas – E-learning with Focus on Content Creation and Evaluation
Study materials and learning in general is moving online nowadays. The paper deals with lifelong learning of socially disadvantaged people. Inhabitants of rural areas represent a substantial group there. The fundamental disproportion of digital divide emerges in combination with other factors, which impacts generally. The problem requires a solution then. The main target groups selected for the study are women on maternity leave, seniors and unemployed school graduates. One of the main focuses was on educational materials and their creation and sharing. Several researches such as semi-structured interviews and surveys have been made among the groups. The results show several requirements for e-learning systems and materials. Taking the everything into account, prototype e-learning applications have been developed (web and mobile).
Lifelong learning, educational materials, online, LMS, e-learning, WWW, mobile devices, applications.
Stočes, M., Masner, J. and Jarolímek, J. (2015) “Mitigation of Social Exclusion in Regions and Rural Areas – E-learning with Focus on Content Creation and Evaluation”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 143 - 150, ISSN 1804-1930. DOI
Impact of Hybrid Intelligent Computing in Identifying Constructive Weather Parameters for Modeling Effective Rainfall Prediction
Uncertain atmosphere is a prevalent factor affecting the existing prediction approaches. Rough set and fuzzy set theories as proposed by Pawlak and Zadeh have become an effective tool for handling vagueness and fuzziness in the real world scenarios. This research work describes the impact of Hybrid Intelligent System (HIS) for strategic decision support in meteorology. In this research a novel exhaustive search based Rough set reduct Selection using Genetic Algorithm (RSGA) is introduced to identify the significant input feature subset. The proposed model could identify the most effective weather parameters efficiently than other existing input techniques. In the model evaluation phase two adaptive techniques were constructed and investigated. The proposed Artificial Neural Network based on Back Propagation learning (ANN-BP) and Adaptive Neuro Fuzzy Inference System (ANFIS) was compared with existing Fuzzy Unordered Rule Induction Algorithm (FURIA), Structural Learning Algorithm on Vague Environment (SLAVE) and Particle Swarm OPtimization (PSO). The proposed rainfall prediction models outperformed when trained with the input generated using RSGA. A meticulous comparison of the performance indicates ANN-BP model as a suitable HIS for effective rainfall prediction. The ANN-BP achieved 97.46% accuracy with a nominal misclassification rate of 0.0254 %.
Rainfall prediction modeling, hybrid computing; rough set, optimal feature reduction, artificial neural network, fuzzy inference algorithm and accuracy.
Sudha, M. and Valarmathi, B. (2015) “Impact of Hybrid Intelligent Computing in Identifying Constructive Weather Parameters for Modeling Effective Rainfall Prediction”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 151 - 160. ISSN 1804-1930. DOI
Analysis of Operating Costs of Subsidies in the Field of Agriculture of EU Countries
The article deals with comparison of agricultural subsidies in the member states of the EU in the period 2004-2012 based on the database Farm Accountancy Data Network (FADN). During the monitored period we found a slight increase of operational subsidies with the fact that variability shows a decreasing trend. In the structure of subsidies we can see a clear transition to payments separated from production with significant differences between original member states and new member states (NMS). With the help of cluster analysis the member states were divided into groups according to their operational subsidies, total production and costs. With the use of correlation analysis we assessed the relationships between production, costs and operational subsidies re-counted per ha of utilised agricultural area. The increase of subsidies will not occur in higher cost productivity and only very slightly will it occur in the higher share of subsidized costs.
Agriculture, Common Agricultural Policy, operational subsidies, outputs, inputs.
Svoboda, J., Lososová, J. and Zdeněk, R. (2015) “Analysis of Operating Costs of Subsidies in the Field of Agriculture of EU Countries”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 161 - 173, ISSN 1804-1930. DOI
The Efficiency Improvement of Central European Corporate Milk Processors in 2008 - 2013
The aim of the article is to evaluate the technical efficiency improvement of the Czech, Polish and Slovak corporate milk processors in the period 2008 – 2013 to identify the possible source of low competitiveness of the Czech and Slovak milk processors towards Poland. The analysis was based on individual data of 130 milk processors (NACE 10.51). The sample covers medium-sized and large companies only. Deflated data on sales, material and energy costs, staff costs and depreciation were used as output and inputs for efficiency calculation. The DEA method was used for calculation of technical efficiency, Malmquist index estimated the efficiency change in time. Two-sample t-test and the analysis of variance enhanced by Sheffe’s test verified the statistical hypotheses. The results proved that the Czech and Slovak milk processors had lower efficiency improvement than Polish companies. Investment activity did not significantly affect the efficiency improvement. The Czech and Slovak milk processors should effectively use quite big amount of public subsidies from the Rural Development Programme in the period 2014 – 2020 to improve the efficiency since the Polish companies outstripped the Czech and Slovak companies in the period 2007 - 2013.
Competitiveness, DEA, financial ratios, Malmquist index.
Špička, J. (2015) “The Efficiency Improvement of Central European Corporate Milk Processors in 2008 - 2013”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 175 - 188, ISSN 1804-1930. DOI
Landmark Finding Algorithms for Indoor Autonomous Mobile Robot Localization
This contribution is oriented to ways of computer vision algorithms for mobile robot localization in internal and external agricultural environment. The main aim of this work was to design, create, verify and evaluate speed and functionality of computer vision localization algorithm. An input colour camera data and depth data were captured by MS® Kinect sensor that was mounted on 6-wheel-drive mobile robot chassis. The design of the localization algorithm was focused to the most significant blobs and points (landmarks) on the colour picture. Actual coordinates of autonomous mobile robot were calculated out from measured distances (depth sensor) and calculated angles (RGB camera) with respect to landmark points. Time measurement script was used to compare the speed of landmark finding algorithm for localization in case of one and more landmarks on picture. The main source code was written in MS Visual studio C# programming language with Microsoft.Kinect.1.7.dll on Windows based PC. Algorithms described in this article were created for a future development of an autonomous agronomical mobile robot localization and control.
Computer vision, localization, MS® Kinect, algorithm, agronomical mobile robot.
Tóth, L., Paulovič, S., Palková, Z. and Vacho, L. (2015) “Landmark Finding Algorithms for Indoor Autonomous Mobile Robot Localization”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp.189 - 197, ISSN 1804-1930. DOI
Agri-Environmental Performance of EU Member states
Agriculture as the primary sector has gained increased attention in terms of its environmental implications. Based on the reform of Common Agricultural Policy, there is a link of direct payments to requirements that farmers maintain land in good agricultural and environmental condition and obey the relevant environment legislation since 2003. The aim of our work is the evaluation of agri-environmental performance of 27 European Union member states (we do not consider Croatia as it is the newest member state and there are missing data). We employ data envelopment analysis to calculate environmental efficiency, and Malmquist index for quantification of productivity change with respect of environmental performance. The results show that in terms of agri-environmental efficiency scores Hungary, Malta, Luxembourg and Netherland are the only efficient countries over the whole observed period (2008-2012). The average output-oriented environmental efficiency is found to be 2.4 over the five observed years. The resulting productivity change is an average decrease of TFP (9%) over the period 2008-2012.
JEL: Q01, Q53, Q57, C38
Agri-environmental performance, DEA, efficiency, desirable output, undesirable output.
Turčeková, N., Svetlanská, T., Kollár and B. Záhorský, T. (2015) “Agri-environmental Performance of EU member states”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 199 - 208, ISSN 1804-1930. DOI
Concept of Horticulture Ambient Intelligence System
In the context of climate changes, there are predictions about the lack of rainfall and water to satisfy the needs of population and farmers. The sustainability of these resources determines watering efficiency in agricultural and horticultural activities. These activities include irrigation and watering. There is scope for the application of intelligent systems for the sustainable management of water resources.
Water, rainfall, irrigation, water resource management, sustainable, horticulture.
Vasilenko, A. and Ulman, M. (2015) “Concept of Horticulture Ambient Intelligence System”, AGRIS on-line Papers in Economics and Informatics, Vol. 7, No. 4, pp. 209 - 216, ISSN 1804-1930. DOI