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Katarzyna Cymbranowicz

Abstract

The article discusses the problem of people who are working, but struggle with poverty. The phenomenon of ‘working poor’ is subjected to a taxonomic analysis, in which the subjective scope is limited to selected European states and the time span to the last twelve years. The aim of the article is to show the relation between work and poverty on European labour markets, including clarifying the level and structure of ‘working poor’. In order to achieve such a research goal, the results of The European Union Statistics on Income and Living Conditions were used, and thanks to the information obtained from the Eurostat database, it was possible to carry out comparable statistical analyses. On the basis of the obtained results, it can be concluded that the working poor phenomenon exists in Europe and in future may get stronger and pose a serious challenge for European labour markets.

Open access

Justyna Brzezińska

Abstract

Latent class analysis has been widely used in the measurement models. Models based on latent variables have a wide range of applications in the presence of repeated ob-servations, longitudinal data, and multilevel data. In this paper we present and apply log-linear analysis as a method for the analysis of multi-way tables. We also present a latent variable model based on a variable that is not directly observed. The basic model postulates an underlying categorical latent variable; within any category of the latent variable the manifest or observed categorical variables are assumed independent of one another (axiom of conditional independence). In this paper we present the results of a survey research based on categorical data and the author`s questionnaire. We present the results of the latent class analysis in the classification of respondents into clusters characterized by similar attitudes and features in economic research. We also conduct a prior log-linear analysis for a multi-way contingency table. All the calculations are conducted in R.

Open access

Maria M. Grzelak, Iwona Laskowska and Elżbieta Roszko-Wójtowicz

Abstract

In contemporary research and economic discussions, a great deal of attention is paid to issues concerning the relationship between competitiveness and research and development (R&D) activity. The measurement and assessment of the impact of R&D activity are extremely difficult but at the same time very important, in particular for authorities determining the level of expenditure on R&D and the method of spending public funds as well as for enterprises assessing the expected profits derived from R&D. The main aim of the article is an attempt to quantify the impact of R&D expenditure on three selected characteristics defining the competitiveness of manufacturing enterprises (gross value added, sold production and labour productivity). The analysis was carried out using panel models. The study makes use of statistical data published by the Central Statistical Office for individual divisions of manufacturing (Section C of the Polish Classification of Activities - PKD) in the years 2009-2016. The conducted analyses indicate that R&D expenditure constitutes a significant determinant of the competitiveness of the analysed divisions of manufacturing.

Open access

Artur Mikulec and Małgorzata Misztal

Abstract

The article presents the results of the duration analysis for 21,163 enterprises (natural persons conducting economic activity) established in the Łódzkie Voivodship in 2010 and observed until December 31, 2015. The Kaplan-Meier estimation of the survival function, the Cox proportionalhazards model and the recursive partitioning method (the CTree algorithm) are applied to achieve the goal of the conducted research i.e. to answer the following question: does the type of business activity and location of the enterprise affect its duration? Prediction error curves based on the bootstrap crossvalidation estimates of the prediction error are used to assess and compare predictions obtained from all three models. On the basis of the analysis results it can be assumed that the type of business activity makes firms more varied due to their duration compared to their location.

Open access

Włodzimierz Kołodziejczak

Abstract

In the Labour Force Survey (LFS) the interviewees are considered as employed, unemployed or professionally inactive based on “objective” criteria defined in the survey’s methodological assumptions (e.g. the fact that a person is seeking employment, waiting to start work or worked at least one hour in the reference week). In use since 1992, the above approach allows the classification to be unaffected by the respondents’ subjective feelings. Since 2006, LFS respondents have been also allowed to identify their economic activity status by themselves. The objective of this paper is to indicate and attempt to explain the differences between the results based on the identification of economic activity statuses as per the criteria adopted by the Central Statistical Office and the LFS respondents’ own assessment of their economic activity status. This paper assessed the rationale behind each approach and the implications thereof for the procedure and results of unemployment surveys from a static and dynamic perspective.

Open access

Witold Bartkiewicz and Zbigniew Gontar

Abstract

There is still many misunderstandings associated with the assessment of the barriers encountered in the process of IT solutions migration to the computational cloud and the benefits to be expected. The purpose of this paper is to organize the criteria used in this field, to analyze the dependencies between them. This will allow us to better understand the problem of migration to the cloud and to improve the decision-making processes related to it. A comprehensive survey was carried out, covering about 400 manufacturing enterprises in Poland using cloud-based IT solutions in various areas. The elements of the study were questions about the barriers and benefits encountered in this process. The paper analyzes the relationships between the obtained categories using diverse data mining methods: association rules mining and hierarchical agglomerative clustering. The obtained results allow to identify the conceptual structure and build a model of relationships inside the problem.

Open access

Marcin Pełka

Abstract

Innovations play a very important role in the modern economy. They are the key to a higher quality of life, better jobs and economy and sustainable development. The innovation policy is a key element of both national and European Union strategy. The main aim of this paper is to present an ensemble clustering of European Union countries (member states) considering their innovativeness. In the empirical section, symbolic density-based ensemble clustering is used to obtain the co-occurrence matrix. The paper uses symbolicDA, clusterSim and dbscan packages of R software for all calculations. Four different clusters where obtained in the result of clustering. Cluster 1 contains highinnovative countries (innovation leaders). This cluster is also the least homogenous. Cluster 2 contains post-communist countries mainly from central Europe. These countries can be seen as rather mid-low innovative (they try to “catch up” with innovation leaders). Cluster 3 contains moderate innovators. Cluster 4 contains two countries that are also mid-innovative.

Open access

Somdeb Lahiri

Abstract

We provide a two good model of oligopolistic production and trade with one good being commodity money. There is the usual demand function of the consumers for the produced good that producer-sellers face. Each seller is a budget constrained preference maximizer and derives utility (or satisfaction) from consuming bundles comprising commodity money and the produced good. We define a competitive equilibrium strategy profile and a Cournotian equilibrium and show that under our assumptions both exist. We further show that at a competitive equilibrium strategy profile, each seller maximizes profits given his own consumption of the produced good and the price of the produced good, the latter being determined by the inverse demand function. Similarly we show that at a Cournotian the sellers are at a Cournot equilibrium given their own consumption of the produced good. Assuming sufficient differentiability of the cost functions we show that at a competitive equilibrium each seller either sets price equal to marginal cost or exhausts his capacity of production; at a Cournotian equilibrium each seller either sets marginal revenue equal to marginal cost or exhausts his capacity of production. We also study the evolution of Cournotian strategies as the sellers and buyers are replicated. As the number of buyers and sellers go to infinity any sequence of interior symmetric Cournotian equilibrium strategies admits a convergent subsequence, which converges to an interior symmetric competitive equilibrium strategy. In a final section we discuss the Bertrand Edgeworth price setting game and show that a Bertrand Edgeworth equilibrium must be a derived from a competitive equilibrium price. Here we show that if at a symmetric competitive equilibrium, the sellers consume positive quantities of the produced good then the competitive equilibrium cannot be a Bertrand Edgeworth equilibrium. Thus, if at all symmetric competitive equilibria the sellers consume positive amounts of the produced good, then a Bertrand Edgeworth equilibrium simply does not exist.

Open access

Apáthy M. Sándor

Abstract

There are numerous attempts to estimate hiking time since the age of the ancient Roman Empire, the new digital era calls for more precise and exact solutions to be implemented in mobile applications. The importance of the topic lies in the fact that route planning algorithms and shortest path problems apply time estimations as cost functions. Our intention is to design a hiking time estimation method that accounts for terrain circumstances as well as personal factors, while the level of accuracy and the simplicity of the algorithm should enable the solution to be utilised in the practice. We refine Tobler’s earlier results to estimate a relation between terrain steepness and hiker’s velocity. Later we use fitted curve to design our novel, personalised hiking time estimation method.

Open access

Massimo Angrisani, Giovanni di Nella, Cinzia di Palo and Augusto Pianese

Abstract

This paper deals with the problem of the optimal rate of return to be paid by a defined contribution pension system to its participants’ savings, namely the rate that achieves the goal of the most favorable returns on their contributions jointly with the sustainability of the pension system.

We consider defined contribution pension systems provided with a funded component, and for their study we use the “theory of the logical sustainability of pension systems” already developed in several previous works. In this paper, we focus on pension systems in a demographically stable state, whereas the productivity of the active participants and the financial rate of return on the pension system’s fund, rates that constitute the “ingredients” of the optimal rate of return on contributions, are modeled by two stochastic processes.

We show that the decisional rule defining the optimal rate of return on contributions is optimal in the sense that it is effective in terms of sustainability, and also efficient in the sense that if the system pays to its participants’ contributions a rate of return that is either higher or lower than the one provided by the rule, then the pension system becomes unsustainable or overcapitalized, respectively.