The paper proposes a new family of continuous distributions called the extended odd half Cauchy-G. It is based on the T-X construction of Alzaatreh et al. (2013) by considering half Cauchy distribution for T and the exponentiated G(x;ξ) as the distribution of X. Several particular cases are outlined and a number of important statistical characteristics of this family are investigated. Parameter estimation via several methods, including maximum likelihood, is discussed and followed up with simulation experiments aiming to asses their performances. Real life applications of modeling two data sets are presented to demonstrate the advantage of the proposed family of distributions over selected existing ones. Finally, a new regression model is proposed and its application in modeling data in the presence of covariates is presented.
Boosting jest jedną z najlepszych metod agregacji modeli dyskryminacyjnych (Bauer, Kohavi, 1999). Liczne badania empiryczne potwierdzają możliwość znacznej poprawy jakości modeli klasyfikacyjnych, niewiele jednakże wiadomo na temat efektywności tej metody w przypadku modeli regresyjnych. Freund i Schapire (1995), stosując swój algorytm AdaBoost.R, podjęli próbę wykorzystania metody boosting do tego typu zagadnień. Głównym celem artykułu jest prezentacja nowej implementacji metody boosting w regresji, która opracowana została przez Ridgeway’a (2005). W przeprowadzonych eksperymentach zbadany został wpływ wartości podstawowych parametrów tego algorytmu, takich jak np. współczynnik uczenia, czy też liczba iteracji, na jakość modelu zagregowanego.
EN
In a wide variety of classification problems, boosting technique have proven to be very effective method for improving prediction accuracy (Bauer, Kohavi, 1999). While more evidence compiles about the utility of these technique in classification problems, little is known about their effectiveness in regression. Freund and Schapire (1995) gave a suggestion as to how boosting might improve regression models using their algorithm AdaBoost.R. The main aim of this article is to present an application of the new boosting method for regression problems which was introduced by Ridgeway (2005). We will discuss the influence of the main parameters of this algorithm, such as eg. learning rate or number of iterations on the model performance.
Szeroko stosowane w praktyce metody nieparametryczne wykorzystujące tzw. drzewa regresyjne mają jedną istotną wadę. Otóż wykazują one niestabilność, która oznacza, że niewielka zmiana wartości cech obiektów w zbiorze uczącym może prowadzić do powstania zupełnie innego modelu. Oczywiście wpływa to negatywnie na ich trafność prognostyczną. Tę wadę można jednak wyeliminować, dokonując agregacji kilku indywidualnych modeli w jeden. Znane są trzy metody agregacji modeli i wszystkie opierają się na losowaniu ze zwracaniem obiektów ze zbioru uczącego do kolejnych prób uczących: agregacja bootstrapowa (boosting), losowanie adaptacyjne (bagging) oraz metoda hybrydowa, łącząca elementy obu poprzednich. W analizie regresji szczególnie warto zastosować gradientową, sekwencyjną, odmianę metody boosting. W istocie polega ona wykorzystaniu drzew regrcsyjnych w kolejnych krokach do modelowania reszt dla modelu uzyskanego w poprzednim kroku.
EN
The successful tree-based methodology has one serious disadvantage: lack of stability. That is, regression tree model depends on the training set and even small change in a predictor value could lead to a quite different model. In order to solve this problem single trees are combined into one model. There are three aggregation methods used in classification: bootstrap aggregation (bagging), adaptive resample and combine (boosting) and adaptive bagging (hybrid bagging-boosting procedure). In the field of regression a variant of boosting, i.e. gradient boosting, can be used. Friedman (1999) proved that boosting is equivalent to a stepwise function approximation in which in each step a regression tree models residuals from last step model.
In this paper an estimator of the finite population mean in the unit nonresponse situation is proposed. It is constructed as a combination of the well-known regression estimator derived from the linear model and a reweighting-type estimator based on a logistic regression model. Combination weights depend on goodness of fit of respective models. Hence, the estimator for which the corresponding model better describes observed sample data dominates in the combination. Some Monte Carlo simulation results revealing its properties are presented.
PL
W artykule zaproponowano estymator złożony średniej w populacji skończonej przy brakach odpowiedzi. Jest on kombinacją estymatora regresyjnego opartego na modelu liniowym i estymatora wykorzystującego ważenie danych opartego na modelu logistycznym. Wagi kombinacji uzależniono od miar dobroci dopasowania tych modeli do danych. Przedstawiono wyniki symulacji wykonanych dla zbadania jego własności.
Consumer's behaviour in the market is a widely studied and analysed problem. Complexity of social, economic and psychological determinants that influence consumer's decision process is a reason for multilevel and multi-factor approaches to analyse this problem. Therefore the aim of this paper is to describe application of parametric regression model for the effectiveness of advertising. The study described is based on a survey covering 550 consumers of dairy product, all of age over 15 and living in one of the nine biggest Polish agglomerations. Built models were examined and verified statistically. Obtained results clearly show that the approach chosen to describe AIDA model is an appropriate method for analysing impact of advertisement on consumer's decision making process.
The paper deals with a first-order autoregression model with parameter estimation with exponential forgetting, known and well established in the mathematical system theory. However, the use of exponential forgetting in econometry is not a standard. Under the assumption of slow timevariability of model parameters and model stationarity, this estimation method could however lead to significant improvement of the prediction quality. In this paper, we describe the Bayesian approach to such a modelling and parameter estimation. The use of the method is demonstrated on a one-step-ahead prediction of the EUR-USD exchange rate.
Research background: The investor`s expectation of better performance in the case of more expensive mutual funds seems natural and fully justified. However, the rise of passive funds and their surprisingly good results, especially when taking into account their low fees, triggered the discussion. Recent years have brought more and more studies, conducted mostly for the American market, discrediting high-charging, aggressive funds. First analyses in Poland also indicate that the level of fees is not always linked with the fund's performance. Purpose of the article: The purpose of the study is to investigate the relation between the fees imposed by the mutual funds and the funds` performance. The idea is to verify, whether higher management fees are associated with top performance and whether it is rational to pay more for capital management. Methods: In the first step of the study, linearity and direction of the dependency was explored, using scatterplots and correlation analysis. In the second part, the linear regression was created to verify the strength of the relation. One-factor models have been built with the rate of return and standard deviation as independent variables for 1-, 3- and 5-year time horizons. Moreover, two-factor models, including both rate of return and risk has been created, to compare the significance of return and risk factor. Findings & Value added: The results indicated that more expensive Polish mutual funds in 2015 tended to perform worse in all tested time horizons - both in terms of lower rates of return and higher risk. Especially unexpected are the results of rates of return regression analysis - it turns out that within a sample 1% higher fee implied over 0.6% lower rate of return before fees (in yearly period). Nonetheless, the risk turned out to be more important, explaining the charges variability much better than the rate of return. Another interesting finding of the study is that merely two simple factors (return and risk) explain even as much as 60% of the management fee variability.
Health care is a dynamically developing sector of the economy, which generates a large amount of useful data about health of the inhabitants of the country and individual regions. These include information on the incidence of selected diseases, data on medical facilities and employees, as well as expenditure on health care. in recent years, many scientific articles about data mining in health care have been published. in this article, presented a review of the literature on health analytics and data mining techniques used in this field. based on the information gathered, the current development in this field and possibilities that can be used in the future are indicated.
In this paper, I consider not only the crisis in conservative neoliberalism and free market economics, but a crisis of representation and plausibility in progressive new liberalism; a situation which leads to deadlock for progressivism in which things cannot progress. In order to address this state of crisis in the global perception of the “white left,” Critical Theory, as a mode of Western liberal thought, needs to rethink the direction of its own criticism. Additionally, Critical Theory needs to adjust its focus to respond to the deadlock presented by the rise of right-wing populism and the derogation of liberal values in these regressive times (I refer antonymically, here, to Jürgen Habermas’s use of the term “progressive”). The radical democratic ideal advocated by Habermas, comprising universal equality and emancipation, should still be the goal for liberalism, and for Critical Theory, but first of all, the achievements and advances liberal progressivism has already made need to be secured to prevent society from regressing. This does not mean making a choice between neoliberalism and authoritarianism, but that a new paradigm of thinking is due. I argue that universality is anterior to cultural pluralism, as are social topics to cultural issues, and justice of distribution to justice of identity. In the complex world of modernity, good things do not come together if there is conflict between desirable values, so choices need to be made: a ranking of real, material conditions is necessary, to ensure cohesion and progression.
The article presents the problem of registering certificates of the congregation of the Kazimierz Deanery outside the native parish. According to the accepted hypothesis the scale of the phenomenon depended on the distance between the nearest church and the place of residence. The research has been based on many sources. In total, the author shave examined the certificates from 13 out of 15 parishes making up the deanery of Kazimierz in the 18th century and additionally a few neighbouring parishes. The collected material has been analysed with the use of the GIS instruments. The results suggest that the scale of the phenomenon was not big. In the case of baptisms, the median of the children baptised outside their native parish was at the level of 3.1. No clear correlation between the number of baptisms and the distance has been detected. On the basis of the results it is possible to conclude that the decisive role in the choice of the place of administering sacraments was the so-called parish coercion. In order to obtain more precise data it seems necessary to enlarge the research basis with certificates from other parishes of the Lublin Voivodeship and to take into consideration a bigger number of the variables that influenced the scale of registering outside the native parish in the statistical analysis.
The article describes disturbing phenomena taking place in Polish speech therapy. It began ambitiously with the culture of the living word, and is moving towards speech therapy care. The consequences of withdrawing speech therapy from the draft Medical Professions Act were also presented.
PL
W artykule opisano niepokojące zjawiska zachodzące w polskiej logopedii, która zaczęła od kultury żywego słowa, a zmierza w kierunku opieki logopedycznej. Ustosunkowano się także do projektu Ustawy o Zawodach Medycznych, postulując zachowanie w niej zawodu logopedy – patologa mowy. Poruszono także podstawowe kwestie związane z planowaniem ustawy o zawodzie logopedy.
In this study, panel regression models for 21 European countries and data covering the period between 2008 and 2014 were used to demonstrate that the distribution of working population across different occupational groups explains cross-country differences in terms of the average effective retirement age. Thus, while the great majority of previous studies verified the causal trade-off investigated on the basis of single-country micro data with reference to one economy, this study takes perspective of cross-country diversity in terms of the investigated relationship. The confirmed link holds even when controlling inter alia for health status, education, unemployment, old-dependency ratio, interest rate, GDP per capita, or the share of salaries and wages in GDP. An important practical implication for the policy-makers is that decisions limited only to the increase in the universal pensionable age cannot be effective, since the occupational composition of an economy is very relevant.
The issue of using the physical method in economics is no longer an innovative idea. However, nowadays the methods of mathematical quantum mechanics are also applied to economic sciences. This is the natural result of the fact that as applicable in quantum mechanics, mathematical spaces and tools turn out to be useful in other fields of science. Then it is possible to assume that the problem of the choice of the space is a universal question that is associated not only with mathematics and physics but also with economics or social sciences. In this paper the author considers various formulations of Hilbert space in relation to finite-dimensional quantum mechanics which constitutes a fundament to also apply my outcomes in economics. On the basis of mathematical considerations the author puts forward the hypothesis that the complex Hilbert space is characterized with numerous advantages in relation to its real and quaternionic alternatives.
In this paper the author tries to explore (or at least to indicate) the problem of the so-cial function of philosophy in the contemporary world. This world is characterized by universal modernization and in the last decades by globalization and unification, but at the same time also by controversies and contradictions which reveal tendencies of hu-man regression and degeneration. Philosophy must remain a study of general and fun-damental nature of a human-produced world. As such philosophy produces potentiali-ties of critical thinking, provides social investigations, and—at least in principle—gives people the power of an adequate understanding of our world, its fundamental character-istics and main tendencies. Thus philosophy is a ground for a reasonable social practice and adequate policies.
This study aims to understand the public’s perception by looking into media news content analysis and surveying of public perception of seven of Sarawak’s newspapers namely Borneo Post, New Sarawak Tribune, Utusan Sarawak, Utusan Borneo, Suara Sarawak, See Hua Daily and Sin Chew Daily were examined. The understanding of the impacts on mediatization of politics and populism towards public perception with Sarawak’s newspapers towards the electoral democracy during Sarawak’s election and Midterm Transition of Malaysia Government 2020 were analysed based on an online survey. The analysis was constructed on 384 respondents using factor analysis (FA) and regression to examine the role of mediatization of politics and populism towards the opinion and perception of the people of Sarawak. The result shows that mediatization of politics scored a total of more than 10% impact towards the opinion and perception of Sarawak’s people where media logic proved an impact of 17% and political logic showed a 12.5% impact. Populism also evinced that a 14.1% impact towards the Sarawak people’s perception.
The Polish version of the article was published in Roczniki Humanistyczne vol. 62, issue 1 (2014). This article is an attempt at an analysis of the changes occurring in the area of Schulz’s narrative identity that is being constituted. It is assumed that the turning point for Schulz’s personal myth was first of all the success of The Street of Crocodiles and a number of events in his personal life (splitting up with his fiancée, his brother’s death, his health problems). Each of these factors starts to influence, in its own way, the writer’s questioning of the possibility to continue writing, that is, interpreting the world, discovering history, “making reality sensible.” The success of The Street of Crocodiles becomes a challenge that is difficult to respond to in these new conditions. The writer’s “brilliant epoch,” the epoch of “writing for himself,” comes to an end. The “Schulz” issue is in danger of sinking into oblivion. The narrative space is gradually transformed into a space of coping with alienation, division, loneliness. These motifs are articulated in a special way in the stories Dodo, The Pensioner, and Loneliness. If, in these stories, overcoming failure in life is indeed impossible (Dodo) or proceeds owing to “sponging off somebody [else]’s life” (The Pensioner), or “parasitizing metaphors” (Loneliness), in The Homeland the rewriting of an individual myth ab origine takes place. The act of this “rewriting” is understood as consequently departing from the basic principles of Schulz’s literary hermeneutics and philosophy of literature. The reality appearing as a result of this departure is a reality that is not rooted in genuine experience, a quasi-reality of “negative values,” a reality of a narrative disaster signaling the definitive “death of Bruno the Great.”
W artykule przedstawiono koncepcję opisu etapów drogi zawodowej (rozwój, stabilizacja, regres) za pomocą stanu wiedzy, umiejętności i kompetencji społecznych pracowników. Przyjęto, że etap jest zmienną zależną, a aspiracje, wielkość przedsiębiorstwa (liczba pracowników), rodzaj stosowanych technologii, kondycja ekonomiczna i świadomość edukacyjna pracodawcy tworzą układ zmiennych niezależnych. Zmienne i występujące między nimi relacje zostały scharakteryzowane i opatrzone komentarzem. Wskazano także na możliwości rozbudowywania przedstawionej koncepcji.
EN
The article presents the concept that describes career stages (development, stabilization, regression) using the knowledge, skills and social competences of the employees. It was assumed that the stage is the dependent variable, and aspirations, size of the company (number of employees), the type of applied technologies, economic condition and educational awareness of employer form a system of independent variables. The variables and relationships between them have been characterized and commented upon. Possibilities of expanding the presented concept have also been pointed out.
This article is focused on two possibilities of perception of transport safety and transport systems. It describes basic characteristics and elements of road safety in the Czech Republic, and differences of safety in rail transport are also remembered. The article discusses traffic accidents as an indicator of road safety. The paper is created with examples of selection and processing of data transport systems, for road and rail transport of the Czech Republic.
Celem rozważań jest wskazanie na ryzyka związane z nieuzasadnionym rozszerzeniem stosowalności różnych modeli. Nadmierne stosowanie metod ilościowych sprawia wrażenie, że wszystko można policzyć, zmierzyć, zaprognozować. Liczyć trzeba, ale trzeba również pamiętać, że nie wszystko co ważne da się policzyć i nie wszystko co da się policzyć jest ważne. W artykule wykorzystano wyniki własnych badań dotyczące zmienności i korelacji indeksów giełdowych, cen wybranych surowców i kursów walutowych. Głównym wnioskiem wynikającym z badań jest konstatacja, że często dokonujemy nadinterpretacji wyników badań i stosowanych metod badawczych. Przypisujemy im właściwości, których często nie posiadają. Jest to bardzo istotne dla praktyki, bo coraz bardziej skomplikowane modele sprawiają wrażenie, iż jesteśmy w stanie, przy ich wykorzystaniu, prognozować przyszłą zmienność zjawisk, określać prawdopodobieństwo ich wystąpienia i ryzyko z tym związane. To jednak nie jest prawda.
EN
An aim of considerations is to indicate the risks connected with the unjustified extension of applicability of various models. The excessive application of quantitative methods makes an impression that everything can be counted, measures, forecast. One should count but one should also remember that not everything what is important is countable, and not everything what is countable is important. In the article, the author used results of his own surveys concerning variability and correlations of stock exchange indices, prices for the selected commodities, and exchange rates. The main conclusion issuing from the surveys is ascertainment that we often misinterpret results of research and the applied research methods. We attribute to them the properties they often lack. This is very important for the practice as more and more complicated models make an impression that we are able, while using them, to forecast the future variability of phenomena, to determine the probability of their occurrence and the risk related thereto. But this is not true.
Value relevance is a concept which states that book values influence the market valuation of a company, the share price, or their rates of return in subsequent periods. Most of the research conducted in this area is based on panel data, synthetically presenting trends observable for a group of companies. In the case of analyses carried out on the example of the Polish capital market, several can be distinguished relating to the empirical impact of profits and balance sheet data on market variables, as well as to the impact of the introduction of new accounting regulations on the degree of value relevance. The research usually ignores companies from the financial sector, but there are also analyses that focus specifically on a group of entities such as banks or insurance companies. In the framework of this study, the latter were taken into account. However, this study presents a different approach from most empirical studies, focusing on the financial data of 1 company from the insurance sector, PZU S.A. The analysis was performed with the use of linear regression models, based on the OLS and the Prais-Winsten method. Financial data from quarterly, semi-annual, and annual reports for 2009–2019 were used. The results of the research indicate that the share prices in the future are explained, in particular, by balance sheet data, mainly technical assets and provisions, and also by operating cash flows, technical result, and net premium. Several models are presented that can be considered useful, taking into account their statistical correctness and the compliance of parameter estimates with theoretical assumptions. This result also indicates the usefulness of research on the concept of value relevance in relation to individual entities.
PL
Value relevance to koncepcja, wedle której wartości księgowe oddziałują na rynkową wycenę spółki, kurs akcji czy ich stopy zwrotu w kolejnych okresach. Większość badań przeprowadzanych w tym zakresie opiera się na danych panelowych, syntetycznie ujmując tendencje obserwowalne dla grupy spółek. W przypadku analiz przeprowadzonych na przykładzie polskiego rynku kapitałowego wyróżnić można kilka odnoszących się do empirycznego wpływu zysków i danych bilansowych na zmienne rynkowe, a także do wpływu wprowadzenia nowych regulacji w zakresie rachunkowości na stopień value relevance. Badania zazwyczaj pomijają przedsiębiorstwa z sektora finansowego, jednakże wyróżnić można także takie, które skupiają się na określonej grupie podmiotów, takich jak banki czy zakłady ubezpieczeń. W artykule pod uwagę wzięto właśnie ostatnią z wymienionych grup. Niemniej zaprezentowano w nim odmienne podejście niż w większości badań empirycznych – skupiono się na danych finansowych jednej spółki z sektora ubezpieczeń: PZU S.A. Analizę przeprowadzono z wykorzystaniem modeli regresji liniowej, stosując modele oparte na MNK i metodę Praisa-Winstena. Wykorzystano dane finansowe pochodzące z raportów kwartalnych, półrocznych i rocznych z lat 2009–2019. Wyniki badania wskazują na objaśnianie kursów akcji w przyszłości szczególnie przez dane bilansowe, przede wszystkim aktywa i rezerwy techniczno-ubezpieczeniowe, a także przez operacyjne przepływy pieniężne, wynik techniczny i składkę na udziale własnym. Przedstawiono kilka modeli, które można uznać za użyteczne, biorąc pod uwagę ich poprawność pod względem statystycznym i zgodność oszacowań parametrów z założeniami teoretycznymi. Rezultat ten wskazuje również na celowość badań w koncepcji value relevance w odniesieniu do indywidualnych podmiotów.
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