Using parametric set constraints for locating errors in CLP programs

This paper introduces a framework of parametric descriptive directional types for constraint logic programming (CLP). It proposes a method for locating type errors in CLP programs and presents a prototype debugging tool. The main technique used is checking correctness of programs w.r.t. type specifications. The approach is based on a generalization of known methods for proving correctness of logic programs to the case of parametric specifications. Set-constraint techniques are used for formulating and checking verification conditions for (parametric) polymorphic type specifications. The specifications are expressed in a parametric extension of the formalism of term grammars. The soundness of the method is proved and the prototype debugging tool supporting the proposed approach is illustrated on examples. The paper is a substantial extension of the previous work by the same authors concerning monomorphic directional types.Comment: 64 pages, To appear in Theory and Practice of Logic Programmin

Quality of Institutions and Total Factor Productivity in European Union

The key challenge for medium- and long-term policy in European Union countries is to use the potential of knowledge-based economy (KBE), which is a condition for maintaining high total factor productivity in Europe. For this reason, the relationship between quality of institutional system and total factor productivity in the EU countries has been examined. The quality of institutional system is defined here from the perspective of incentives that influence the use of the potential of KBE. In order to determine the level of effectiveness of the institutional system in the analyzed countries the method for linear ordering of objects was applied based on data from Fraser Institute. The main hypothesis of the article was formed as follow: the quality of institutional system in the context of KBE has significant influence on the level of total factor productivity in the EU. In order to verify the hypothesis, the parameters of the Cobb-Douglas production function were estimated, which allowed to evaluate TFP for EU countries. The calculation made in the article was based on Eurostat data. Then, the identification of the relationship between the quality of institutional system and the level of TFP was made with the application of panel model. The research made for the years 2000-2010 allowed to verify the hypothesis

Human Development and Quality of Institutions in Highly Developed Countries

The article concentrates on the problem of influence of quality of institutional system in the context of utilizing the potential of knowledge-based economy on the human development in highly developed countries. In order to measure the quality of institutional system the proposed synthetic measure with multivariate analysis - TOPSIS method based on the data available from Fraser Institute was obtained. As diagnostic variables of quality of institutions 29 variables qualified to four aspects of quality of national institutional systems were used: a) formal regulations influencing entrepreneurship; b) effectiveness of juridical system in keeping low level of transaction costs and supporting effectiveness of market mechanism; c) competitive pressure and effectiveness of labour markets; d) financial markets institutions as a stimulator of development of enterprises with high growth potential. Human Development Index proposed within United Nations Development Programme was used for measuring the quality of life. The estimation of relation between institutions and human development was made with econometric dynamic panel model. The estimation was made for 24 European Union countries for the years 2004-2010. The econometric analysis shows the positive influence of quality of institutions on human development in the context of knowledge-based economy in highly developed countries

RESEARCH AND DEVELOPMENT EXPENDITURES AND QUALITY OF LIFE IN EUROPEAN UNION COUNTRIES

The improvement of people’s quality of life is currently considered as the main responsibility of every government. Due to the emergence of knowledge-based economy, it is commonly believed that investments in research and development (R&D) at a given level are a necessary condition for creating growth-based on innovations, thus supporting welfare in developed countries. In this context, the article is devoted to the analysis of influence of R&D expenditures on the quality of life in the European Union countries. As the main measure of the quality of life Human Development Index was utilized. Thus, the article can be considered as a contribution to the discussion on the potential of HDI index for measuring the quality of life in the case of narrow group of relatively developed countries. In the empirical part of the paper, panel data modeling fulfilling the postulates of dynamic estimation was used. The research was done for EU countries for the period 2004–2010. The empirical part takes into consideration the structural diversity between “old” and “new” members of the EU. First of all, the results can be treated as a voice confirming the usefulness of HDI as a measure of quality of life also from the perspective of narrow group of highly developed countries. Then, the research confirms the positive influence of R&D on European welfare only in the case of highly developed “old” member

Business angels and early stage decision making criteria: empirical evidence from an emerging market

How do business angels assess a prospective entrepreneurial firm when they make an investment decision? This article examines a central question that informal venture capitalists have been struggling with for decades: What early stage decision making criteria do investors define and apply to reduce the volume of potential deals to a more manageable size? Based on semi-structured interviews with business angels in an emerging market, we show that investors are focused on the industry structure and product features, on the other side, our results also suggest a very strong support for the personality of the entrepreneur and management team. More specifically, entrepreneur trustworthiness is an essential element affecting an investor’s decision to close a deal. Business angels set requirements in terms of the entrepreneur’s equity stake in the start-up and monitoring tools to prevent the failure of investee firms. Our findings suggest that if there are warning signs that the project is in an existential crisis, most of the investors will reject their participation. We believe that our empirical results support both researchers and practitioners to establish a better understanding between the well-developed financial theories and the underresearched informal venture capital market in a Central and Eastern European country

How well does B-type natriuretic peptide predict death and cardiac events in patients with heart failure: systematic review

Objective To assess how well B-type natriuretic peptide (BNP) predicts prognosis in patients with heart failure. Design Systematic review of studies assessing BNP for prognosis m patients with heart failure or asymptomatic patients. Data sources Electronic searches of Medline and Embase from January 1994 to March 2004 and reference lists of included studies. Study selection and data extraction We included all studies that estimated the relation between BNP measurement and the risk of death, cardiac death, sudden death, or cardiovascular event in patients with heart failure or asymptomatic patients, including initial values and changes in values in response to treatment. Multivariable models that included both BNP and left ventricular ejection fraction as predictors were used to compare the prognostic value of each variable. Two reviewers independently selected studies and extracted data. Data synthesis 19 studies used BNP to estimate the relative risk of death or cardiovascular events in heart failure patients and five studies in asymptomatic patients. In heart failure patients, each 100 pg/ml increase was associated with a 35% increase in the relative risk of death. BNP was used in 35 multivariable models of prognosis. In nine of the models, it was the only variable to reach significance-that is, other variables contained no prognostic information beyond that of BNP. Even allowing for the scale of the variables, it seems to be a strong indicator of risk. Conclusion Although systematic reviews of prognostic studies have inherent difficulties, including die possibility of publication bias, the results of the studies in this review show that BNP is a strong prognostic indicator for both asymptomatic patients mid for patients with heart failure at all stages of disease

Parameterized complexity of the MINCCA problem on graphs of bounded decomposability

In an edge-colored graph, the cost incurred at a vertex on a path when two incident edges with different colors are traversed is called reload or changeover cost. The "Minimum Changeover Cost Arborescence" (MINCCA) problem consists in finding an arborescence with a given root vertex such that the total changeover cost of the internal vertices is minimized. It has been recently proved by G\"oz\"upek et al. [TCS 2016] that the problem is FPT when parameterized by the treewidth and the maximum degree of the input graph. In this article we present the following results for the MINCCA problem: - the problem is W[1]-hard parameterized by the treedepth of the input graph, even on graphs of average degree at most 8. In particular, it is W[1]-hard parameterized by the treewidth of the input graph, which answers the main open problem of G\"oz\"upek et al. [TCS 2016]; - it is W[1]-hard on multigraphs parameterized by the tree-cutwidth of the input multigraph; - it is FPT parameterized by the star tree-cutwidth of the input graph, which is a slightly restricted version of tree-cutwidth. This result strictly generalizes the FPT result given in G\"oz\"upek et al. [TCS 2016]; - it remains NP-hard on planar graphs even when restricted to instances with at most 6 colors and 0/1 symmetric costs, or when restricted to instances with at most 8 colors, maximum degree bounded by 4, and 0/1 symmetric costs.Comment: 25 pages, 11 figure

Niekeynesowskie skutki polityki fiskalnej w krajach strefy euro, ze szczególnym uwzględnieniem wpływu na proces konwergencji gospodarczej

Ostatni kryzys finansowy doprowadził do znaczących akcji stymulacji fiskalnej w przypadku większości krajów wysoko rozwiniętych, co przełożyło się na istotny wzrost ich poziomu zadłużenia. Zjawisko to występuje także w krajach strefy euro oraz szerzej w krajach Unii Europejskiej. Czynnik ten prawdopodobnie zmusi w przyszłości wiele krajów Unii do przyjęcia znacznie bardziej restrykcyjnej polityki fiskalnej w średnim i długim okresie. W tym kontekście przeprowadzone badanie ma na celu stwierdzenie czy w ostatnich dekadach występowały epizody niekeynesowskich dotowań fiskalnych w krajach strefy euro. Jeżeli odpowiedź na tak postawione pytanie jest pozytywna, należy stwierdzić, czy niekeynesowskie skutki polityki fiskalnej stanowiły znaczący czynnik rozwojowy. Kolejny problem badawczy postawiony w niniejszej pracy koncentruje się na sposobie przeprowadzenia konsolidacji fiskalnych oraz wpływie strategii konsolidacyjnych na krótkookresowe tempo wzrostu gospodarczego. Przeprowadzone badanie bazuje na danych z raportów Komisji Europejskiej oraz danych za bazy Eurostatu dla lat 1995-2013. W analizie zastosowano dynamiczny model panelowy do badania warunkowej β-konwergencji. Jako uzupełniającą metodę badawczą wykorzystano analizę jakościową znaczących konsolidacji fiskalnych, ze szczególną koncentracją na różnicach w sposobie przeprowadzenia zacieśnień przynoszących niekeynesowskie i keynesowskie skutki. Przeprowadzone badanie dostarcza argumenty na rzecz tezy o istnieniu kanałów transmisji fiskalnej, które mogą prowadzić do niekeynesowskich skutków polityki fiskalnej. W tym samym czasie mogą one stanowić istotny czynnik warunkowej β-konwergencji