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991.
A framework for the detection of change points in the expectation in sequences of random variables is presented. Specifically, we investigate time series with general distributional assumptions that may show an unknown number of change points in the expectation occurring on multiple time scales and that may also contain change points in other parameters. To that end we propose a multiple filter test (MFT) that tests the null hypothesis of constant expectation and, in case of rejection of the null hypothesis, an algorithm that estimates the change points.The MFT has three important benefits. First, it allows for general distributional assumptions in the underlying model, assuming piecewise sequences of i.i.d. random variables, where also relaxations with regard to identical distribution or independence are possible. Second, it uses a MOSUM type statistic and an asymptotic setting in which the MOSUM process converges weakly to a functional of a Brownian motion which is then used to simulate the rejection threshold of the statistical test. This approach enables a simultaneous application of multiple MOSUM processes which improves the detection of change points that occur on different time scales. Third, we also show that the method is practically robust against changes in other distributional parameters such as the variance or higher order moments which might occur with or even without a change in expectation. A function implementing the described test and change point estimation is available in the R package MFT. 相似文献
992.
Mario González María del Mar Alonso-Almeida David Dominguez 《Quality and Quantity》2018,52(3):1041-1055
This study maps the General Reporting Initiative (GRI) relations for a set of global enterprises. Enterprise interrelationships are built using the Mutual Information (MI) of the data reported by enterprises. From the MI topology, we describe interrelationships among the enterprises using chord diagrams to represent the inter- and intra-connectivity between geographical regions and economic sectors globally, by continent and country. Detailed maps are presented for European and Asian regions/sectors, including the relationship between Europe and Asia’s top reporting countries. Our findings reinforce previous research regarding the role of Europe as a driver of sustainability and its influence worldwide. We also determined that Spain is a major player in Europe and that Northern Europe does not have the assumed leading role mentioned in related studies. Eastern Asia is, by far, the leader of the region, and the GRI maps demonstrate the preponderant role of China in the region and the minimal role of India. MI topology maps outline the behavior of the economic sectors, for all the studied regions. Furthermore, a measure that relates the inter- to intra-connections is presented to describe the internal an external relationships among regions/sectors. 相似文献
993.
Paris Aslanidis 《Quality and Quantity》2018,52(3):1241-1263
Populism is a concept employed to qualify the political behavior of a large number of actors at a worldwide scale, with scientists classifying the latter into populists and non-populists according to dimensions such as ideology, strategy, discourse, economic policy, and even style. This article analyzes existing schools of thought on the nature of populism and argues that conceptualizing populism as a specific type of anti-elite discourse in the name of the People is both conceptually and methodologically the most coherent and useful way to understand the phenomenon. Additionally, it suggests discarding crude, dichotomous classification in favor of a gradated view of populist mobilization by means of quantifying populist discourse and observing its spatial and temporal variation. It adds value to current methods of measurement by demonstrating why and how clause-based semantic text analysis can provide optimal quantitative results while retaining qualitative elements for mixed-methods analysis. Aiming, moreover, at expanding the scope of populism studies by overcoming a narrow view that focuses exclusively at party system developments, it applies semantic text analysis to the study of grassroots mobilization during the Great Recession. Results point to the wide use of populist discourse on the part of movement activists seeking an inclusive language when framing disparate social grievances in a given constituency, a finding with important implications with regards to how populism can facilitate straddling the divide that purportedly distinguishes institutionalized party system behavior from the social movement milieu. 相似文献
994.
Edsel L. BejaJr. 《Quality and Quantity》2018,52(4):1817-1829
The paper retests the U-shaped relationship between happiness and age using the cross-classified multilevel regression procedure and the World Values Survey data. The analysis accounts for period and cohort effects. The results reconfirm the pattern that happiness is U-shaped in the life course. That is, happiness decreases from a high-point in young adulthood, reaches a low-point in midlife, and thereafter increases to arrive at another high-point in old age. The results show that the high-point of happiness in old age is lower than the high-point of happiness in young adulthood. That happiness does not return to its initial high-point after it drops to a low-point in midlife is perhaps another stylized fact in the relationship between happiness and age. 相似文献
995.
996.
Death, injury, conflict, and disorder caused by natural and man-made disasters have resulted in significant challenges to good governance and impeded the goal of achieving the benign development of society. This paper uses a particular method for analyzing the research situation and identifying current trends and focuses. It then proceeds to explore future research needs. The study finds that future researchers will shift their emphasis from the risks caused by natural disasters to those arising from man-made disasters; meanwhile, the study will consider the complex systems of interaction to understand causality. The objectives of management, hence, should change from investigating the impacts of risks to crisis control. Eventually, an evolutionary disaster-based social-risk framework is established, and some suggestions for future research are provided. 相似文献
997.
Nesrin Menemenci Bahçelerli 《Quality and Quantity》2018,52(1):43-58
Learning is the accumulated knowledge acquired from the experiences of individuals. Lifelong learning concept for adult learners is vital to reveal and sustain their knowledge creation experience. Lifelong Learning can be defined as the ability to develop an individual’s skills, knowledge and skills social, individual, and professional. This study addresses the concept of lifelong education. Lifelong education is provided through informal, formal and non-formal education processes. This research relies on documentary analysis. It was applied the key arguments for the research focus. The relationship between technology and lifelong learning is becoming more important. The importance of lifelong learning in tourism education is increasing. The vocational school can create lifelong opportunities for the tourism industry. These research explained that some perspectives of lifelong learning; such as dimensions, benefits and barriers. Additionally, the chapter proposes a perspective on the lifelong learning strategy in tourism education and discuss concept of lifelong learning, in regard to the literature. It is the most important factor that reflects the training and professional development of the staff and the competitive power of the tourism product directly and indirectly. Vocational schools should develop programs in line with the expectations of tourism enterprises. 相似文献
998.
This paper focuses on entrepreneurship by academic leaders. With the use of patents, inventions, and spin‐offs to measure commercialization, and directors, research group leaders, and business owners as academic leaders, results, using a sample of more than 2,500 German researchers, show differences across academic leaders and commercialization. Findings for spin‐offs are different from those for patents and inventions. Academic leaders in sciences were more likely to commercialize. Doctoral degrees helped patents by business owners and spin‐offs by group leaders, whereas female business owners and female group leaders faced challenges patenting and inventing, respectively. For business owners, age increased the likelihood of patenting but lowered spin‐offs. 相似文献
999.
The purpose of this research is to determine the levels and use of perception management by school administrators. The study group consists of teachers working in Private Primary School and Secondary Schools affiliated to the Ministry of National Education in Nicosia, the Turkish Republic of Northern Cyprus in the 2016–2017 academic year. The sample of the study is composed of 282 teachers representing the universe selected by the method of easy reachable case sampling. As a means of collecting data in the survey, “Personal Information Form” by Kline (An easy guide to factor analysis, Routledge, New York, 1994) and “Manager Perception Management ent Scale” developed by Uylas (Yönetici Alg? Yönetimi Ölçe?i, Türkiye Ölçme Araçlar? Dizini, 2017a, Okul Yöneticilerinin Sosyal-Duygusal E?itim Liderli?i ve Alg? Yönetimine ?li?kin Ö?retmen Görü?leri, T.C. Abant ?zzet Baysal Üniversitesi, E?itim Bilimleri Enstitüsü, Bolu, 2017b) was used. The obtained data were analyzed in an analysis program. In the research, the values of perception management use levels of managers according to teacher opinions were examined. According to the results and comments obtained from the research, some of the proposals developed for researchers and educators working in the field of education management are as follows. Towards practical; trainings can be given on how school administrators can use perception management for successful perception management practices in educational organizations. In interviews to select school administrators, choosing school administrator with high perception management skills can be prioritized. Towards newstudies; including multidimensional evaluation of all elements of educational organizations such as managers, parents and servants in new researches to be conducted and comparison of teachers ‘and administrators’ views. This study has brought out suggestions that can be implemented in other stages of education. 相似文献
1000.
Didier Nibbering Richard Paap Michel van der Wel 《International Journal of Forecasting》2018,34(2):288-311
This paper studies what professional forecasters predict. We use spectral analysis and state space modeling to decompose economic time series into trend, business cycle, and irregular components. We examine which components are captured by professional forecasters by regressing their forecasts on the estimated components extracted from both the spectral analysis and the state space model. For both decomposition methods, we find that, in the short run, the Survey of Professional Forecasters can predict almost all of the variation in the time series due to the trend and the business cycle, but that the forecasts contain little or no significant information about the variation in the irregular component. 相似文献