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EN
European Commission Regulation (EU) No. 445/2011 regarding the system of certification for entities in charge of maintenance (ECM) of freight wagons requires such entities to supervise the condition of wagons, without specifying the methods of supervision to be used. Each ECM should establish a Maintenance Management System (MMS), which will include the obligation to monitor the fleet of freight wagons. Monitoring railway vehicle maintenance operations should include tracking all significant technical and operational indicators. The key question is which indicators are the have the greatest impact on safety. This paper discusses some issues related to the monitoring of maintenance operations for railway vehicles. It also looks at dedicated solutions for entities in charge of the maintenance for freight wagons based on PN-EN 50126:2002 standard and RAMS indicators (Reliability, Availability, Maintainability and Safety). This paper describes factor analysis of the proposed indicators as a means of selecting those that have a decisive impact on the correctness of the process for monitoring vehicles. This paper shows an example of the implementation of the requirements of the European Commission Regulation 445/2011 [3] regarding the monitoring of the state of railway vehicles and the possibility of using the information so gained as part of a process of continuous improvement. Reducing the number of indicators will reduce the amount of data needed to calculate all the RAMS indicators, without compromising the benefits of the rail vehicle monitoring system.
EN
Geometry has always contributed to a great extent and played a significant role in the development of many of the principles of the factor models. While factor-analytic principles and procedures have been generally developed by the heavy emphasis on matrix algebra, there is still a grave importance and need towards a geometrical approach and its application in the factor analysis. In this article the author provides, on selected issues, a description in reference to factor models from a geometric viewpoint with a discussion running through its advantages and disadvantages. Finally, at the end of the paper, conclusions in reference to good conditions of factors rotation are given. This article explains to what extent a geometrical approach brings specific value and offers an extra insight into factor analysis. As proved, geometry still provides an alternative framework which may be helpful for better understanding and data structure diagnosis.
EN
This paper leverages the IMF’s Financial Access Survey (FAS) database to construct a new composite index of financial inclusion. The topic of financial inclusion has gathered significant attention in recent years. Various initiatives have been undertaken by central banks both in advanced and developing countries to promote financial inclusion. The issue has also attracted increasing interest from the international community with the G-20, IMF, and World Bank Group assuming an active role in developing and collecting financial inclusion data and promoting best practices to improve financial inclusion. There is general recognition among policy makers that financial inclusion plays a significant role in sustaining employment, economic growth, and financial stability. Nonetheless, the issue of its robust measurement is still outstanding. The new composite index uses factor analysis to derive a weighting methodology whose absence has been the most persistent of the criticisms of previous indices. Countries are then ranked based on the new composite index, providing an additional analytical tool which could be used for surveillance and policy purposes on a regular basis.
EN
Effective corporate governance is a key element in achieving long-term success for any company. The codes of conduct that corporate governance adopts directly determine the sustainability of business activities. With this in mind, this paper aims to demonstrate the results of research that identifies a set of key indicators of corporate governance performance. The presented research is quantitative. In order to identify key performance indicators, factor analysis was employed. It was found that corporate governance performance is influenced by two factors. For the first factor, the relationship between corporate governance and stakeholders is measured by key indicators: percentage of women within CG, contributions to political parties, politicians and related institutions and number of complaints received from stakeholders. The second factor, strategy & compliance, is generated from the following: percentage of strategic objectives met and total number of sanctions for breaching the law. This research aims to assist both academic and corporate practitioners who want to improve corporate governance performance and, through the use of key performance indicators, support the transparency and sustainability of their business.
EN
In the literature four basic postulates of transport are usually mentioned: time, convenience, cost and security of travel. The hierarchy of importance of individual postulates of transport depends on subjective evaluations of urban transport users. In the research carried out within the framework of research work financed from funds for science in 2010-2013 titled ‘Reference Model of City logistics and the quality of Life of Inhabitants’, measured the difference between the expected and perceived quality of urban transport services and defined a hierarchy of evaluated quality criteria. The solution to the problem with too many variables is the possibility of using factor analysis. This analysis allows the reduction of many interrelated variables
EN
Camptothecin is a fluorescent compound exhibiting strong anticancer properties. A serious limitation to clinical application of this compound is its hydrolysis, when biologically active lactone form converts into inactive carboxylate. There are some differences in the shapes of both fluorescence and absorption spectra of the lactone and carboxylate forms of camptothecin. Therefore, during hydrolysis resultant fluorescence and absorption spectra evolve. Factor analysis of fluorescence/absorption spectra recorded during the hydrolysis process of camptothecin enables one to determine the temporary concentration of the lactone and carboxylate forms and obtain the deactivation rate of this compound.
EN
The aim of the paper is to identify development ways and effectiveness of RIGA International Airport. Theoretical evidence was examined and expert in-depth interview was carried out to explore the main circumstances affecting RIGA International Airport functioning. Findings of the study show that there are positive tendencies in the field of airport efficiency and development, but improvement is needed primarily for coordinating visions and resources managed by both state and airport administration bodies.
EN
Building professional identities of student teachers at the beginning of their vocational education and professional training provides opportunities to explore diversity of practice and provide external support. In the available literature, there is only a small number of studies that explore the professional identity of pre-service and student teachers. The main problem of this research is to examine self-reported attitudes toward student teachers’ professional identity dimensions. The second aim of the presented study was examining the reliability and concurrent validity of the Student Teachers Professional Identity Scale (Fisherman & Abbot, 1998), which was used for the first time in Serbia. The initial sample of respondents consisted of 158 students from the Faculty of Pedagogical Sciences. Results indicate that university students perceive teaching roles more as a specific job and not as a profession. They are goal-directed towards their job as teachers and perceive their practice as a part of their studies and not as a result of their professional identity development as teachers. The mentioned scale (for one-factor solution with the satisfactory criterion of confirmatory factor analysis) obtained very good reliability (α = .935) and concurrent validity indicators and values. Researching professional identity at early career stages can help educators to emphasize the multidimensionality and complexity of the teaching profession.
PL
W artykule przedstawiono wybrane zagadnienia związane z analizą wielowymiarową i ich potencjalne zastosowanie do modelowania procesów rozdrabniania w prasach walcowych. Proces rozdrabniania w prasie charakteryzuje wiele parametrów technicznych, technologicznych oraz wskaźników, które są wzajemnie powiązane ze sobą. Przedstawione podejście polega na zbadaniu struktury w grupie analizowanych zmiennych oraz zaprezentowanie analizy interpretacyjnej polegającej na wyodrębnieniu czynników powiązanych z wybranymi zmiennymi wejściowymi (parametrami operacyjnymi urządzenia i procesu). W wyniku tego otrzymujemy model opisujący zjawisko, który ułatwia analizę i interpretację badanego procesu.
EN
Chosen issues concern the multi dimensional analysis and their potential application for modeling of comminution processes in roller presses were presented in the article. The comminution process in HPGR can be described with using many technical and technological parameters and indices, which are mutually connected. The presented approach assumes the investigation over the structure of analyzed variables, and presents the interpretation consisted in marking off the factors related to the input variables (operating parameters of the comminution process). The model characterizing the issue, obtained as a result of research, makes easier the interpretation of the process under analysis.
EN
Objective. This study aimed to analyze the factor structure of the simplified Beck Depression Inventory BDI-S translated from German and attempted for a theoretical justification of its items based on the theory of homeostatically protected mood. BDI-S uses a frequency scale instead of the original rating of the degree of the measured behavior by separate descriptions (21x4 descriptions); thus creating a tool with a four times lower number of items. Method. The questions were answered by N = 1108 people aged from 18 to 70. As in the case of BDI-II, the PAF (principal axis factoring) method and oblique rotation (Promax) were used on half of the participants to analyze the structure of BDI-S; and CFA was used on the other half of the participants. Gender invariance was verified and factor reliability was determined. Results. Using EFA the two-factor structure found by the authors of the original BDI-II questionnaire in students (cognitive-affective dimension, factor 1; and somatic dimension, factor 2) was not supported, but the somatic-affective and cognitive dimensions, which were found by the authors of the original BDI-II in patients (Beck et al., 1996) were supported. CFA confirmed the identified two-factor structure, which was invariant in terms of gender. Conclusions. The two identified dimensions of BDI-S in the general population represent the contents identified by BDI-II in patients. An attempt to apply the theory of homeostatically protected mood seems to be unsuccessful for two reasons: a) In the questionnaire, depressed mood and loss of pleasure and interest are not sufficiently represented, namely, they were not represented by the separate factor in the results; b) In the general population, it can be expected that there will be no longer-lasting negative change in the homeostatically protected mood. Study limitation. The results may have been affected by online data collection at the time of the pandemic.
XX
Perception of school autonomy was measured by the International Civic and Citizenship Education Study (ICCS) 2009, allowing potential cross-national comparison. The possibility of a common, general scale for all countries participating in the study was investigated. Using multi-group confirmatory and exploratory factor analysis, measurement invariance was tested for countries, such that meaningful comparisons for the concept could be made. The results show that the concept is not necessarily comparable between all countries involved in the ICCS but that secondary data analysis is generally feasible depending on the research questions posed and the methodology applied. The scientific and practical implications of this reach are discussed.
EN
In the study, environmetric methods were successfully performed a) to explore natural and anthropogenic controls on reservoir water quality, b) to investigate spatial and temporal differences in quality, and c) to determine quality variables discriminating three reservoirs in Izmir, Turkey. Results showed that overall water quality was mainly governed by “natural factors” in the whole region. A parameter that was the most important in contributing to water quality variation for one reservoir was not important for another. Between summer and winter periods, difference in arsenic concentrations were statistically significant in the Tahtalı, Ürkmez and iron concentrations were in the Balçova reservoirs. Observation of high/low levels in two seasons was explained by different processes as for instance, dilution from runoff at times of high flow seeped through soil and entered the river along with the rainwater run-off and adsorption. Three variables “boron, arsenic and sulphate” discriminated quality among Balçova & Tahtalı, Balçova & Ürkmez and two variables “zinc and arsenic” among the Tahtalı & Ürkmez reservoirs. The results illustrated the usefulness of multivariate statistical techniques to fingerprint pollution sources and investigate temporal/spatial variations in water quality.
EN
According to the modal superposition method, the vortex vibration procedure of submerged floating tunnel cable was compiled using Matlab, based on the calculated results, the fatigue damage was predicted. The effects of various factors, such as cable density, cable length, and pretension and velocity distribution on vortex induced fatigue damage in the cable were studied. The results show that velocity distribution has more effect on the cable fatigue damage than cable length, cable density and pretension. Secondly, cable length has also relatively effect on the cable damage fatigue, cable density and pretension has limited in a certain range.
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EN
In this research work we investigate which factors influence the probability of leaving the unemployment state among people registered in the District Labor Office in S lupsk. The multiepisode hazard models with time-varying variables are suitable tools for this analysis. We introduced the changing labor market structure into the risk model. The main results achieved show that the job finding process depends on the historical time of the entry into the unemployment state and the actual historical time. Also, the specific individual characteristics of people unemployed, such as gender, age, marital status, place of residence, education level, influence the probability of exiting the unemployment state. There is a greater tendency to leave the unemployment state when the person doesn’t receive the unemployment benefit. The participation in the vocational training doesn’t increase the transition rate into employment.
EN
The purpose of the work was to determine the relationship between the of the water quality parameters in an artificial reservoir used as cooling ponds. Factor analysis were applied to analyze eighteen physico- -chemical parameters such as air and water temperature, dissolved oxygen concentration, visibility of the Secchi disk, concentrations of total nitrogen, ammonium, nitrate, nitrite, total phosphorus, phosphate, concentrations of calcium, magnesium, chlorides, sulfates and total dissolved salts, pH, chemical oxygen demand and electric conductivity from 2002-2019 to investigated cooling water discharge. Exploratory factor analysis allowed identified four factors were obtained from 54.1% (in discharge zone) to 56.7% (in dam zone). In discharge and pelagic zones confirmatory factor analysis showed that four latent variables: salinity, temperature, nitrogen and phosphorus provide good fit, but in the dam zone the better fit was obtained for the latent variables salinity, temperature, nutrient and eutrophic. Correlations between latent variables temperature, nitrogen, phosphorus or nutrient and eutrophic show a significant effect of temperature on the transformation of nitrogen and phosphorus compounds.
EN
This article seeks to show that, although factor analysis (mostly in its exploratory version) is a method frequently applied by social-science researchers (it is often also discussed in basic data analysis textbooks), only a very basic version of it is used, with settings that are far from optimal. However, what settings are used can have major implications, primarily in the form of conceptual problems, where the exploratory version is often used instead of the confirmatory version. Other settings used can also have an impact on the results. These are mainly partial options, which are used mainly in the exploratory version, in particular the choice of the correct correlation coefficients, the choice of method for the initial extraction of factors, the choice of the rotation method and the choice of the number of factors with which we want to work in the exploratory version. The text discusses the algorithms for ordinal variables, and the possibility of determining the number of factors through parallel analysis or MAP. The practical example discusses the advantages of the oblique rotation of factors. The article seeks to highlight good practices that best reflect the current state of the art of quantitative methodology and statistics. In addition to the general guidelines, the article contains practical advice about software and recommends a procedural schema for using factor analysis.
EN
European Commission Regulation (EU) No. 445/2011 regarding the system of certification for entities in charge of maintenance (ECM) of freight wagons requires such entities to supervise the condition of wagons, without specifying the methods of supervision to be used. Each ECM should establish a Maintenance Management System (MMS), which will include the obligation to monitor the fleet of freight wagons. Monitoring railway vehicle maintenance operations should include tracking all significant technical and operational indicators. The key question is which indicators are the have the greatest impact on safety. This paper discusses some issues related to the monitoring of maintenance operations for railway vehicles. It also looks at dedicated solutions for entities in charge of the maintenance for freight wagons based on PN-EN 50126:2002 standard and RAMS indicators (Reliability, Availability, Maintainability and Safety). This paper describes factor analysis of the proposed indicators as a means of selecting those that have a decisive impact on the correctness of the process for monitoring vehicles. This paper shows an example of the implementation of the requirements of the European Commission Regulation 445/2011 [3] regarding the monitoring of the state of railway vehicles and the possibility of using the information so gained as part of a process of continuous improvement. Reducing the number of indicators will reduce the amount of data needed to calculate all the RAMS indicators, without compromising the benefits of the rail vehicle monitoring system.
EN
Enterprise innovation is currently becoming a recognized factor of the competitiveness, survival, and development of companies in the market economy. Managers still need recommendations on ways of stimulating the growth of innovation in their companies. The objective of this paper is to identify the strategic factors of enterprise innovativeness in the area of technology, defined as the most important internal factors positively impacting the innovativeness of enterprises in a strategic perspective. Empirical studies were conducted using the Computer-Assisted Web Interview (CAWI) method on a purposive sample of N = 180 small and medium-sized innovative industrial processing enterprises in Poland. Data analysis was performed using Exploratory Factor Analysis within the Confirmatory Factor Analysis framework (E-CFA) and Structural Equation Modeling (SEM). Empirical research shows that the strategic factor of enterprise innovativeness in the area of technology is technological activity. A technologically active company should (1) possess a modern machinery stock, (2) conduct systematic technological audits, and (3) maintain close technical cooperation with the suppliers of raw materials, consumables, and intermediates. The implementation of the indicated recommendations by managers should lead to increased innovativeness of small and medium-sized industrial companies. The author recommends the use of the presented research procedure and data analysis methods in further studies.
19
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EN
An effect of factors determining water quality in the water supply network in Kraków is assessed. The data collected over a four-year research period included quality parameters of water taken from the water distribution system in the period between 1 January 2011 and 31 December 2014. In the analysis the supply zones of four municipal water treatment plants in Krakow were considered. The selection of 29 water sampling points within the supply area allowed comparing water quality with respect to operational and technological aspects. Factor analysis enabled 4 components explaining correlations between tap water quality variables to be distinguished. It follows from the research performed that the obtained factors applied to 77% of overall water variability. The highest share was assigned to factor 1 that explained 32% of the chemical composition of water under consideration and was correlated with calcium, conductance, nitrates (V), magnesium and to a moderate extent with Σ THM (with negative sign).
EN
The main aim of the paper is to present the methodological basis of market segmentation which uses not only demographic-social attributes and preferences but also variables defining values with important meaning in personal life of customers. The construction of a psychometric test is discussed on the basis of the example of a semiometric scale. This test uses principal components analysis in order to distinguish the main dimensions of cultural dichotomies. The example of measurement on the semiometric scale comes from the examination of preferences in the range of the life and medical insurances.
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