Currently, there are no computerized tools enabling objective interpretation of observational gait assessment based on Wisconsin Gait Scale, which is a reliable and well-tested tool. The solution envisaged by us may provide a practical tool for assessing gait deviations in patients with hemiparesis after stroke. The present study assessed agreement between a new application software for computerized WGS and 3-dimensional gait analysis, and reliability of the application. The study involved 33 individuals with hemiparesis after stroke. The software was developed based (...) on a model designed taking into account components of the WGS and incorporating auxiliary lines passing through the relevant anthropometric points on the patient’s body, as well as measurements of angular values, distances and duration of the specific gait phases, which make it possible to substantiate assessment based on this scale. Series of videos were made to record gait of the qualified patients. After the gait evaluation was carried out using the app, the data were retrieved from the software. The gait assessment was performed separately by three independent examiners who reviewed the video recording using the new app twice. Additionally, 3DGA was carried out for all the subjects, and the results of the app-aided assessment were compared to those acquired using 3DGA. The findings show statistically significant correlations between majority of the WGS items measured using the new app, and the relevant spatiotemporal and kinematic parameters identified by 3DGA. Agreement between the scores reported by the three examiners was high in both measurements, as reflected by Cronbach’s alpha exceeding 0.8. The findings reflect very good intra-observer reliability and inter-observer reliability of the new application software for computerized WGS. The opportunities offered by the observational gait scale objectified through our new software for computerized WGS result from the fact that the tool provides a useful low-cost and time-effective feedback to monitor ongoing treatments or formulate hypotheses. (shrink)

Approximately one in six top economic research papers draws an explicitly causal conclusion. But what do economists mean when they conclude that A 'causes' B? Does 'cause' say that we can influence B by intervening on A, or is it only a label for the correlation of variables? Do quantitative analyses of observational data followed by such causal inferences constitute sufficient grounds for guiding economic policymaking? The Philosophy of Causality in Economics addresses these questions by analyzing the meaning of causal (...) claims made by economists and the philosophical presuppositions underlying the research methods used. The book considers five key causal approaches: the regularity approach, probabilistic theories, counterfactual theories, mechanisms, and interventions and manipulability. Each chapter opens with a summary of literature on the relevant approach and discusses its reception amongst economists. The text details case studies, and goes on to examine papers which have adopted the approach in order to highlight the methods of causal inference used in contemporary economics. It analyses the meaning of the causal claim put forward, and finally reconstructs the philosophical presuppositions accepted implicitly by economists. The strengths and limitations of each method of causal inference are also considered in the context of using the results as evidence for policymaking. This book is essential reading to those interested in literature on the philosophy of economics, as well as the philosophy of causality and economic methodology in general. (shrink)

The impact of background category information on the creation of social cliques: The role of need for cognitive closure and decisiveness This article focuses on the role of need for cognitive closure in the process of mental model creation about social relations. We assumed that high need for closure participants tend to rely on background category information when forming social cliques. We predicted that this tendency to employ categorical information as a mental aid, used in order to form social cliques, (...) would be efficient in simple task structures but would lead to increased error rates in complex task structures. The results confirmed our predictions, showing especially strong effects for the decisiveness component of need for closure. The importance of individual differences in need for closure and decisiveness in social reasoning is discussed. (shrink)

In his recent paper in the Journal of Economic Methodology, Tobias Henschen puts forth a manipulationist definition of macroeconomic causality that strives for adequacy. As the notion of ‘adequacy’...

A survey of the main approaches in a mind study -oriented part of Artificial Intelligence is made focusing on controversial issues and extreme hypotheses. Various meanings of terms: "intelligence" and "artificial intelligence" are discussed. Limitations for constructing intelligent systems resulting from the lack of formalized models of cognitive activity are shown. The approaches surveyed are then recapitulated in the light of these limitations.

The aim of this article is to point to the unsolved research problems connected to causation in the philosophy of economics. First, the paper defines causation and discusses two notable approaches, i.e. the realist theory of causation and the instrumentalist theory of causation. Second, it offers a review the current research activity focusing on the problem of causation in economics. Third, it discusses several case studies. On the grounds of comparison of the research practice of economists and the current issues (...) undertaken by the philosophers of economics, the paper concludes that there is a gap between the research practice and the normative methodological analyses and indicate the research questions that need to be addressed. (shrink)

I consider the problem of existence of virtual objects, mainly their mode of existence, while omitting the issue of the criteria of their existence. I present and analyze the concepts of modes of existence of virtual objects proposed in the literature of the subject, and then I demonstrate my own position on the issue. My position on the existence of virtual objects has certain points coinciding with the already postulated views, but at the same time it differs from them in (...) some basic aspects. In my view virtual objects are “born” in human individual consciousness as the objects of specific creative states of the mind. So initially they are private objects belonging to the individual subjective sphere. However, their final and ready forms emerge in complex processes of objectifying and autonomizing the respective private conscious states and their objects. In these processes the private objects are transformed into objects intersubjectively accessible and existing in the collective cultural sphere. In both their forms, initial and final, virtual objects are non-material entities: first subjective, then objective. The ontic status of virtual objects is very similar to the status of intangible ideas and all the non-material objects created by the human mind. The main difference consists in that virtual objects are expressed by the use computers programmes, while other non-material objects created by human beings are expressed by use of words, pictures, literature and art works, etc. (shrink)

It is consistent that for every function there is an uncountable set and two continuous functions such that f {f0, f1} for every A2,α≠β.

W ostatnich latach mamy do czynienia z dynamicznym rozwojem neuroetyki, tj. subdyscypliny nauk o mózgu badającej rozmaite zagadnienia etyczne w kontekście funkcjonowania ludzkiego umysłu i mózgu. Centralnym przedmiotem tych badań jest specyficznie ludzka zdolność do wydawania sądów moralnych oraz jej mechanizmy. Tymczasem twierdzenia neuroetyki mają znacznie szerszy wymiar; wykracza on bowiem poza kwestie czysto opisowe i obejmuje swym zasięgiem zagadnienia teoretyczne etyki. W niniejszym artykule rozważam znaczenie badań neuroetycznych dla analiz przeprowadzanych w obszarze etyki normatywnej oraz metaetyki.

Artykuł składa się z dwóch części. W części pierwszej rekonstruuję filozoficzne poglądy polskiego filozofującego fizyka Czesława Białobrzeskiego, a w drugiej części przedstawiam jego biografię oraz wkład w rozwój fizyki. Filozoficzne rozważania Białobrzeskiego kształtowały się na bazie wiodących problemów w fizyce końca XIX i przede wszystkim XX wieku; Białobrzeski prowadził te rozważania w ścisłym związku ze swoją praktyką naukową. Działalność polskiego uczonego przypada na okres powstawania i rozwoju mechaniki kwantowej. Białobrzeski – jak wielu innych ówczesnych fizyków – był świadomy konieczności spójnego (...) wyjaśniania fundamentalnie nowych zjawisk świata atomowego. Jego wyjaśnienie jest oryginalne – odwołał się mianowicie w nim do klasycznej, filozoficznej teorii kategorii i zaproponował jej własną ontologiczną interpretację. (shrink)

The current strategy of searching for an effective treatment for COVID-19 relies mainly on repurposing existing therapies developed to target other diseases. Conflicting results have emerged in regard to the efficacy of several tested compounds but later results were negative. The number of conducted and ongoing trials and the urgent need for a treatment pose the risk that false-positive results will be incorrectly interpreted as evidence for treatments’ efficacy and a ground for drug approval. Our purpose is twofold. First, we (...) show that the number of drug-repurposing trials can explain the false-positive results. Second, we assess the evidence for treatments’ efficacy from the perspective of evidential pluralism and argue that considering mechanistic evidence is particularly needed in cases when the evidence from clinical trials is conflicting or of low quality. Our analysis is an application of the program of Evidence Based Medicine Plus to the drug repurposing trials for COVID. Our study shows that if decision-makers applied EBM+, authorizing the use of ineffective treatments would be less likely. We analyze the example of trials assessing the efficacy of hydroxychloroquine as a treatment for COVID-19 and mechanistic evidence in favor of and against its therapeutic power to draw a lesson for decision-makers and drug agencies on how excessive hypothesis testing can lead to spurious findings and how studying negative mechanistic evidence can be helpful in discriminating genuine from spurious results. (shrink)

Conflicting results undermine making inferences from the empirical literature. So far, the replication crisis is mainly seen as resulting from honest errors and questionable research practices such as p-hacking or the base-rate fallacy. I discuss the malleability (researcher degrees of freedom) of quantitative research and argue that conflicting results can emerge from two studies using different but plausible designs (e.g., eligibility criteria, operationalization of concepts, outcome measures) and statistical methods. I also explore how the choices regarding study design and statistical (...) techniques bias results in a way that makes them more or less relevant for a given policy or clinical question. (shrink)

A considerable group of contemporary philosophers and theologians—including those engaged in the science-theology dialogue, such as Barbour, Clayton, Davies, and Peacocke—supports panentheism, i.e., a theistic position which assumes that the world is in God, who is yet greater than everything he created. They see it as a balanced middle ground between the positions of classical theism and pantheism. In this article, I offer a presentation and a critical evaluation of the most fundamental principles of panentheism from the point of view (...) of classical theism. First, I list six main species of panentheism and the motivations of those who support it. In the second part, I analyze the three main difficulties concerning its ontological and theological principles, i.e., (1) the meaning of the preposition ‘in’ (_en_) in ‘pan_en_theism’; (2) the accuracy of panentheistic definition of divine immanence, and (3) the question of whether panentheism is successful in protecting God’s transcendence. I conclude that panentheism fails as a Christian theistic position. Nevertheless, it might still be valuable and play an important role in addressing the cognitive drama of the modern human beings, often seduced by secular (scientific) or spiritual naturalism, or pantheism. (shrink)

Volume 27, Issue 3, September 2020, Page 266-268.

It is well-established that topos theory is inherently connected with intuitionistic logic. In recent times several works appeared concerning so-called complement-toposes, which are allegedly connected to the dual to intuitionistic logic. In this paper I present this new notion, some of the motivations for it, and some of its consequences. Then, I argue that, assuming equivalence of certain two definitions of a topos, the concept of a complement-classifier is, at least in general and within the conceptual framework of category theory, (...) not appropriately defined. For this purpose, I first analyze the standard notion of a subobject classifier, show its connection with the representability of the functor Sub via the Yoneda lemma, recall some other properties of the internal structure of a topos and, based on these, I critically comment on the notion of a complement-classifier. (shrink)

Dialectical contradictions influence organizational processes in distinct ways and create a unique dynamics in terms of leadership process in entrepreneurialorganizations. We integrate research from charismatic, transformational, and organizational literature, as well as entrepreneurship literature, to create a generalized model of entrepreneurial leadership that is descriptively robust and conceptually distinct from existing concepts. We focus specifically on visionary, transformational, and motivational contradictions of entrepreneurial leadership and conclude by discussing the implications of organizational reconciliation of these three contradictions for leadership research and (...) practice. (shrink)

The paper is an attempt to defend the Chisholm's metaphysical doctrine called mereological essentialism. The main thesis of mereological essentialism states that for any objects x and y - if x is ever a part of y, then y is necessarily such that x is a part of y, i.e. that all parts of y are essential to it (y has them at any time that y exists). This radical theory gives a categorisation of all objects via entia per se (...) and entia successiva. The paper contains a critical survey of the theory of mereological essentialism: it deals with some important arguments against it and answers as well. The author tries to show that in defence of the theory and the categorisation in question the applicability of the doctrine of mereological essentialism must be somehow limited. He suggests that the best way in doing so is to restrict theses of mereological essentialism either only to objects qua occurrents or only to objects qua continuants or only to persons. (shrink)

Based on case studies prepared at the Harvard Business School, the article analyses the content of university courses on business history. Its aim is to answer the question whether or not business history courses are used for discussing the problems of CSR or moral dilemmas behind strategic decisions made by managers. The article argues that the chance of enhancing the understanding of social problems on the part of the managers and shaping their responsiveness to them, created by the presence of (...) courses on history in the academic curriculum, remains, to a large extent, unrealised. Teaching materials are still influenced by the Chandlerian paradigm and thus focus on changes in organisational structures and strategies of large multinational companies. They pay little attention to the social environment of business, rarely pose questions on the motivations of human actions or value hierarchies and avoid discussions on the social consequences of management decisions. (shrink)

The idea of the university was never a significant context for researchers of Franz Kafka work. It was the other social institutions that became the natural source of allusive recognition of literary scholars. In this sketch – written on the margins of Kafka’s famous short story: Report for the Academy – we are trying to change it. The university here becomes a “central object of criticism”, an institution in ruins, a place where one does not practice research and does not (...) perfect humanistic virtues. On the contrary, it is a space where the “gate of perception” and „critical thinking” are consistently closed – as a tribute to the particular game of interests. In the worst case – the effect of the Academy’s impact becomes destruction resulting from training and humiliation. (shrink)

This article examines the dynamics that allowed the derogatory term “Ostjuden” to reappear in academic writing in post-Holocaust Germany. This article focuses on the period between 1980’s and 2000’s, complementing earlier studies that focused on the emergence of the term “Ostjuden” and on the complex representations of Eastern European Jews in Imperial and later Weimar Germany. It shows that, despite its well-evidenced discriminatory history, the term “Ostjuden” re-appeared in the scholarly writing in German and has also found its way into (...) German-speaking public history and journalism. This article calls for applying the adjectival term “osteuropäische Juden”, using a term that neither essentializes Eastern European Jews nor presents them in an oversimplified and uniform manner. (shrink)

L'idea di scrivere questo libro sul diritto naturale e nata dal desiderio dell'autore di approfondire il problema della fondazione della norma morale, nella convinzione che un'autentica visione giusnaturalistica apre nuove orizzonti per comprendere meglio la questione di Dio e dell'uomo nel discorso normativo che si inserisce armonicamente nella dimensione ecclesiale. Il tema ha avuto origine dall'osservazione del dialogo interdisciplinare tra toelogia morale, filosofia del diritto e scienze giuridiche. Prende in esame la relazione tra ordine morale e giuridico individuando le questioni (...) che si pongono per la teologia morale in quanto disciplina che tratta i problemi della fondazione della norma morale. La problematica verte sul temine natura normativa la quale si esplica in veste di progetto antropologico. La rinascita del pensiero giusnaturalistico in Germania e il fulcro di questa tesi. (shrink)

We revisit John Worrall’s old but still prominent argument against the view that randomization balances the impact of both known and unknown confounders across the treatment and control arms. We argue that his argument involving indefinitely many possible confounders is at odds with statistical theory as it (1) presumes that the purpose of randomized studies is obtaining perfect point estimates for which perfect balance is needed; (2) mistakes equalizing each confounder with the overall (average) impact of all confounders, and (3) (...) assumes that the joint effect of an infinite series of confounders cannot be bounded. We defend the role of randomization in balancing the impact of confounders across the treatment and control arms by putting forward the statistical sense of the balance claim. It involves the following three commitments: (1) randomization balances confounders in expectancy, (2) for RCTs to deliver unbiased estimates of the causal effect (true average treatment effect), the balance in the average effect of all confounders and not balancing each confounder is sufficient, and (3) randomization allows for calculating the probability of deviating from the balance. The paper includes a review of how the balance claim has been understood so far and discusses recent arguments supporting randomization balancing the impact of confounders in expectancy and the crucial role of the average impact of all actual confounders, and shows how statistical analysis of RCTs conducted both at the design and analysis stage makes possible estimating the probabilities of deviating from the balance. (shrink)

W oparciu o koncepcję Richarda Rorty’ego oraz Hansa-Georga Gadamera poddano analizie hermeneutyczną ideę integracji estetycznej, oraz autokreacji a także omówiono ich znaczenie dla transformacji paradygmatycznej, której efektem jest społeczeństwo ponowoczesne. Przedstawiono relację pomiędzy poznawczą i integrującą funkcją doświadczenia sztuki. Wykorzystując argumentację Stanisława Ignacego Witkiewicza omówiono związki pomiędzy doświadczeniem katastrofy historycznej a możliwością transformacji paradygmatycznej. Przedstawiono powody, dla których integracja estetyczna nie może stać się narzędziem powstrzymującym katastrofę. On experiencing catastrophe, art and postmodern society Basing on the concept by Richard Rorty (...) and Hans George Gadamer a hermeneutic idea of aesthetic integration and self-creation is analysed and their significance for paradigmatic transformation, which results in postmodern society, is discussed. The relation between cognitive and integrating function of experiencing the art is presented. Relations between experiencing historical catastrophes and the opportunity of paradigmatic transformation are discussed with the use of the argumentation of Stanisław Ignacy Witkiewicz. The reasons why aesthetic integration cannot become the tool to stop the catastrophe are presented. (shrink)

Vacuum Genesis and Spontaneous Emergence of the Universe from Nothing in Reference to the Classical Notion of Causality and Creation ex nihilo The article discousses philosophical and theological reflections inspired by the cosmological model of the origin of the universe from quantum vacuum through quantum tunneling and the model presented by Hartle and Hawking. In the context of the thesis about the possibility of cosmogenesis ex nihilo without the need of God the creator, the question is being raised concerning the (...) ontological status of nothingness and of the laws of nature in the aforementioned models. After pointing to the fact that they do not imply an absolute nothingness in the philosophical sense, the main objectives of both models and philosophical-theological conclusions they inspire are interpreted in the light of the classical principles of potency and act, theory of causation and chance events in nature, elements of classical theology of creation and the classification of sciences in terms of various levels of abstraction, proposed by Aquinas. Noting the fact that some cosmologists cross methodological boundaries of their science, we emphasize the role and significance of their research in a deeper understanding of the philosophical aspects of the origins of the universe, especially the role of potency in the first stages of its existence and evolution. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Evolution and Creation—A Response to Michael Chaberek's Critique of Theistic EvolutionMariusz Tabaczek O.P.Translated by Monika Metlerska-ColerickIntroductionMichael Chaberek's critique of my "Afterword" to the Polish edition of Thomistic Evolution: A Catholic Approach to Understanding Evolution in the Light of Faith is essentially focused on three points. First of all, Chaberek questions my thesis supporting the compatibility of evolutionary theory with the Christian faith in creation. Secondly he discounts the possibility (...) of reconciling evolution with the Aristotelian-Thomistic philosophical tradition. Finally he provides arguments undermining the theory of evolution as the best scientific explanation for the diversity of species observable in the world.1 Because I do not undertake an analysis [End Page 255] of strictly biological problems in the "Afterword," in the present response I will concentrate on the first two points only.2 I trust that engaging in a discussion with Chaberek's views in this respect provides an opportunity to broaden and clarify my position regarding the issue which is the subject of our dispute. To begin with, I would like to stress that, in exploring the topic from the perspective of the Aristotelian-Thomistic tradition of philosophy and theology, I am moving in the sphere of possible interpretations and new approaches. Therefore, I do not treat the aforementioned tradition in an inflexible and dogmatic manner.3 [End Page 256]The Definition of CreationI should start my response to Chaberek's critique by invoking the definition of creation as elaborated by Aquinas. After all, it seems that the disagreement referred to in the present article focuses, to a large extent, on the comprehension of the divine act of creation. My views on this matter are not, in my estimation, a significant alteration of the teaching of St. Thomas. Rather, they are an attempt at drawing conclusions from some of his intuitions regarding creation, which appear in various sections of the body of his work.4According to St. Thomas, the word "creation" (creatio) has two crucial and inextricably linked meanings: (I) creation in an active sense (divine action) and (II) creation in a passive sense (receiving divine action). Within the scope of the first meaning, St. Thomas distinguishes between: (Ia) the primary act of creation, defined as bringing the entirety of being into existence out of nothing (ex nihilo), without any prior existing matter, and (Ib) maintaining contingent beings in their existence and essence. The consequence of (Ia) and (Ib) is contingent beings' full dependence on God regarding what they are and the fact that they are (exist), which determines the essence of creation in the passive sense (II).Regarding (Ia), St. Thomas—in a neo-Platonic vein, in support of the claim that nothingness cannot be the object of God's action in the act of creation—states that "we must consider not only the emanation of a particular being from a particular agent, but also the emanation of all being from the universal cause, which is God; and this emanation we designate by the name of creation" (ST I, q 45, a. 1, corp.). It is worth adding here that, according to St. Thomas, the matter, which is the result of the act of creation, is not indefinite, as is assumed by Chaberek when he refers to creation as the bringing out of nothing "of a certain primordial matter of an indefinite form."5 On the contrary, Aquinas states explicitly that "primary matter was not created altogether formless, nor under any one common form, but under [End Page 257] distinct forms" (ST I, q. 66, a. 1, corp., ad 2), enumerating, at this point, the forms of the four elements: earth, water, air, and fire.In reference to (Ib), St. Thomas defines the divine act of maintaining contingent beings in existence and essence (in the fact that they are, as well as in what they are) as conservatio rerum. What is more, even though he emphasizes that "the preservation of things by God is a continuation of that action whereby He gives existence" (ST I, q. 104, a. 1, ad 4), Aquinas does not employ the currently popular concept of continual creation (creatio continua). It seems that... (shrink)

Over the years, the Austrian School of Economics has created the image of a thinker associated with ideas of liberalism. The views of members of this school are often considered controversial. However, the concept of freedom clearly displayed by the Austrians is very popular among economists. Carl Menger is said to be the founder and a leading member of the Austrian School of Economics, and his works are mostly devoted to methodology and economic theory. Nevertheless, you can also find his (...) views on the sphere of economic liberalism and freedom. Almost 150 years after the publication of Menger’s main works, it emerged that he had created not only the timeless foundations of the theory and methodology of economics, but his theory of subjective value had become the bedrock which is used to this day in deliberations on economic liberalism. The economy pursued by Menger (based primarily on the ideas of subjectivism and individualism) continues to be an important and timeless foundation for the development of the doctrine of economic liberalism. This article is a review based on an analysis of the literature on the subject. (shrink)

[The paper is in Polish, an English abstract is given only for information.] This article is intended for philosophers and logicians as a short partial introduction to category theory and its peculiar connection with logic. First, we consider CT itself. We give a brief insight into its history, introduce some basic definitions and present examples. In the second part, we focus on categorical topos semantics for propositional logic. We give some properties of logic in toposes, which, in general, is an (...) intuitionistic logic. We next present two families of toposes whose tautologies are identical with those of classical propositional logic. The relatively extensive bibliography is given in order to support further studies. (shrink)

The methodological nonreductionism of contemporary biology opens an interesting discussion on the level of ontology and the philosophy of nature. The theory of emergence (EM), and downward causation (DC) in particular, bring a new set of arguments challenging not only methodological, but also ontological and causal reductionism. This argumentation provides a crucial philosophical foundation for the science/theology dialogue. However, a closer examination shows that proponents of EM do not present a unified and consistent definition of DC. Moreover, they find it (...) difficult to prove that higher-order properties can be causally significant without violating the causal laws that operate at lower physical levels. They also face the problem of circularity and incoherence in their explanation. In our article we show that these problems can be overcome only if DC is understood in terms of formal rather than physical (efficient) causality. This breakdown of causal monism in science opens a way to the retrieval of the fourfold Aristotelian notion of causality. (shrink)

This paper offers an Aristotelian-Thomistic response to the question whether AI is capable of developing virtue. On the one hand, it could be argued that this is possible on the assumption of the minimalist (thin) definition of virtue as a stable (permanent) and reliable disposition toward an actualization of a given power in the agent (in various circumstances), which effects that agent’s growth in perfection. On the other hand, a closer inquiry into Aquinas’s understanding of both moral and intellectual virtues, (...) and a more detailed analysis of the ontological status of AI, show that it is highly unlikely to envision the design of specifically human-like reason-based and/or behavioral-based (“strong”) AI that would possess properly human virtues. Still, virtuous “weak AI” might be possible, although a question ought to be asked whether we should classify artifacts’ virtues using categories developed in reference to specifically human dispositions and actions. (shrink)

One of the main challenges of the nonreductionist approach to complex structures and phenomena in philosophy of biology is its defense of the plausibility of the theory of emergence and downward causation. The tension between remaining faithful to the rules of physicalism and physical causal closure, while defending the novelty and distinctiveness of emergents from their basal constituents, makes the argumentation of many proponents of emergentism lacking in coherency and precision. In this article I aim at answering the suggestion of (...) several thinkers to redefine emergence and downward causation in terms of the broader Aristotelian view of causation. In addition, I further develop this interdisciplinary conversation to include theological implications of emergentism, analyzed in reference to Aquinas’ understanding of divine action in terms of the same fourfold division of causes—bringing thus natural science, philosophy, and theology into creative and fruitful dialogue. (shrink)

Making more accurate marketing decisions by managers requires building effective predictive models. Typically, these models specify the probability of customer belonging to a particular category, group or segment. The analytical CRM categories refer to customers interested in starting cooperation with the company, customers who purchase additional products or customers intending to resign from the cooperation. During building predictive models researchers use analytical tools from various disciplines with an emphasis on their best performance. This article attempts to build a hybrid predictive (...) model combining decision trees and cluster analysis. During experiments five different cluster validity indices and eight datasets were used. The performance of models was evaluated by using popular measures such as: accuracy, precision, recall, G-mean, F-measure and lift in the first and in the second decile. The authors tried to find a connection between the number of clusters and models' quality. (shrink)