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11.
The recent literature has analyzed binary choices dynamics providing interesting results. Most of these contributions consider interactions within a single group. Nevertheless, in some situations the interaction takes place not only within a single group but also between different groups. In this paper, we investigate the choice dynamics when considering two populations where one serves as a reference group. Considering this influence effect enriches the dynamics. Although the structurally stable resulting dynamics are attracting cycles only, with any positive integer period, the reference group makes the dynamics of the influenced population much more complex. We considered both the possibility that the reference group has the same or the opposite attitude toward the distribution over the choices. We show how the dynamics and the bifurcation structure are modified under the influence of the reference group. Our results illustrate how the propensity to switch choices in the reference groups may, indirectly, affect choices in the first group. 相似文献
12.
We study the exploitation of a common groundwater resource, first as a static and then as a differential game, in order to take into account the strategic and dynamic interactions among the users of the resource. We suppose that firms can form coalitions or can decide not to cooperate. The non-cooperation regime is characterized by pumping that lead to depletion of the aquifer; the cooperation preserves the resource. Open-loop and feedback equilibria have been computed and compared in order to characterize the existence of cooperators and defectors in water resources management. 相似文献
13.
Peter C. Young 《International Journal of Forecasting》2018,34(2):314-335
The main objective of this paper it to model the dynamic relationship between global averaged measures of Total Radiative Forcing (RTF) and surface temperature, measured by the Global Temperature Anomaly (GTA), and then use this model to forecast the GTA. The analysis utilizes the Data-Based Mechanistic (DBM) approach to the modelling and forecasting where, in this application, the unobserved component model includes a novel hybrid Box-Jenkins stochastic model in which the relationship between RTF and GTA is based on a continuous time transfer function (differential equation) model. This model then provides the basis for short term, inter-annual to decadal, forecasting of the GTA, using a transfer function form of the Kalman Filter, which produces a good prediction of the ‘pause’ or ‘levelling’ in the temperature rise over the period 2000 to 2011. This derives in part from the effects of a quasi-periodic component that is modelled and forecast by a Dynamic Harmonic Regression (DHR) relationship and is shown to be correlated with the Atlantic Multidecadal Oscillation (AMO) index. 相似文献
14.
15.
We propose a new framework exploiting realized measures of volatility to estimate and forecast extreme quantiles. Our realized extreme quantile (REQ) combines quantile regression with extreme value theory and uses a measurement equation that relates the realized measure to the latent conditional quantile. Model estimation is performed by quasi maximum likelihood, and a simulation experiment validates this estimator in finite samples. An extensive empirical analysis shows that high‐frequency measures are particularly informative of the dynamic quantiles. Finally, an out‐of‐sample forecast analysis of quantile‐based risk measures confirms the merit of the REQ. 相似文献
16.
In 2016, German corporations invested 33.5 billion euros in on-the-job-trainings. Communication trainings, especially those for executives, play an important part in on-the-job-trainings and adult education. This study examines how basics of communication and media studies are used in the praxis of communication trainings. We ask which theories of interpersonal communication are being used in communication trainings for executives and for what reasons trainers choose specific theories. The answer can help us understand how executives view communication processes and which criteria make a theory praticable in the eyes of practitioners.First, we define communication trainings as part of on-the-job training and give an overview of research regarding the use of theories in trainings. Research shows that theories play an important role in communication trainings, but that the trainings lack theoretical depths and complexity. The existing research stems mostly from linguistics; the perspective of communication and media studies is missing. In addition, none of the existing studies considers criteria for a practicable theory.In a second step, the canon of theories of interpersonal communication in communication and media studies is identified via a content analysis of seven textbooks and encyclopedias. Overall, these books present 38 theories of interpersonal communication, but only eight theories are presented in three or more books. These eight theories, among them Symbolic Interactionism (Mead), the Theory of Social Systems (Luhmann) and the Four-Ears-Model (Schulz von Thun), build the canon of theories of interpersonal communication in this study.This canon is the basis for the main part of our study. Sixteen communication trainers were interviewed, using the method of qualitative expert interview. The trainers answered questions regarding their professional background, typical courses of training, their goals in trainings, the role of theories in trainings, requirements of the executives being trained and the exchange between colleagues in the occupational field.Results show that trainers use about 15 to 20% of the training time to convey theoretical basics. The Four-Ears-Model by Schulz von Thun dominates the examined trainings. Scientists regard this communication-psychological model as being rather popular scientific. Still, every interviewed trainer uses it. This finding shows that most trainers regard communicational misunderstandings as a result of the four-dimensional character of a message (Who is the sender? Why is he talking to me like that? What are the facts about? What shall I do, think, feel based on the message?). The Communication Axioms by Watzlawick are used as the second most common approach.Apart from theories of interpersonal communication, the trainers mentioned several psychological methods and approaches with therapeutic traits, like Transaction Analysis (Berne) or Active Listening (Rogers).The explorative findings suggest that the trainers chose the theories they use—especially the Four-Ears-Model and Communication Axioms—because it is easy to interlock these theories and the praxis of communication trainings, because they are comprehensible and easy to use in examples, and because they show the relativity of communication processes. Moreover, trainers use theories to explain human behavior and the sources for misunderstandings.These criteria alone do not explain the trainers’ theory choices, though. It became clear in the interviews that factors of socialization, like advanced training for the trainers, play a major role in influencing their training content. Trainers teach the theories which they themselves learned in further education programs becoming a trainer, and they barely look out for new and/or alternative theories.We recommend that communication trainers look for other theories in communication and media studies, like the Symbolic Interactionism. This theory complies with the trainers’ criteria for good theories. Communication and media scholars on the other hand should work together with educational institutions and advanced training to improve the transfer of their theories into the praxis of communication trainings. 相似文献
17.
Stephen G. Dimmock William C. Gerken Zoran Ivković Scott J. Weisbenner 《Journal of Financial Economics》2018,127(1):113-135
Differences in accrued gains and investors’ tax-sensitivity induce variation in a capital gains lock-in effect across mutual funds even for the same stock at the same time. Exploiting this variation, we show this effect influences funds’ governance decisions: higher capital gains decrease the likelihood a fund exits prior to contentious votes and increase the likelihood a fund votes against management. Consistent with tax motivation, these findings are concentrated among funds with tax-sensitive investors. Further, high aggregate capital gains across funds holding a stock predict a higher likelihood management loses a vote and a lower likelihood a contentious vote is proposed. 相似文献
18.
Growing urbanisation in South Africa is reflected in burgeoning Working class and informal township settlements on the fringes of its major towns and cities. Paired with this is an increasing reliance on cash as the primary means of economic transaction, which has in turn stimulated the growth of micro-enterprise business activities within the township context. This article discusses the findings of an eight-township small-area census which occurred between 2010 and 2013 in Cape Town, Johannesburg, Ekurhuleni and Durban townships representing 250 000 residents. The researchers were able to establish the scope and scale of informal food and drink retailing in these localities. Of the 10 049 micro-enterprises located in the study, some 3966 (or 39% of the total) trade in food. These include enterprises in primary production, fresh produce retailing, grocery retailing from house and spaza shops, and informal foodservice enterprises. Food is the basis for much township informal business and plays an important role in making food increasingly affordable and locally accessible, and in creating cash employment. The article builds on the knowledge base of the township informal economy role in bolstering food security needs for the marginalised. 相似文献
19.
Without guaranteed compensation, granted by the German Renewable Energy Sources Act (Erneuerbare Energien Gesetz/EEG), biogas plants compete with all other plant types on the market for electrical energy. However, exchange-based electricity products do not currently permit an economically viable operation of biogas plants owing to their cost situation. 相似文献
20.
Brian E. Gravel Eli Tucker-Raymond Kaitlin Kohberger Kyle Browne 《International Journal of Technology and Design Education》2018,28(4):921-938
Making as a design-centered learning activity has recently received significant attention in education. We use literacies—how individuals use representations to learn—to explore the STEM literacy practices of experienced designers and makers. Describing makers’ representational practices in STEM contexts can inform the design of literacy supports for young makers that can encourage their use of representations to connect STEM disciplines and design practices. We interviewed experienced makers to describe one literacy practice central to design: identifying, organizing, and integrating information. Makers enacted this practice within specific making processes—e.g., designing—with the purpose of sourcing and navigating information related to their chosen problems. The research supports efforts to bridge learning while making with learning in schools by positioning STEM literacies as central practices involved in the processes of designing and making. 相似文献