Return migration, wage differentials, and the optimal migration duration

In simple static models, migration increases with the wage differential between host- and home-country. In a dynamic framework, and if migrations are temporary, the size of the migrant population in the host country depends also on the migration duration. This paper analyses optimal migration durations in a model which rationalises the decision of the migrant to return to his home country, despite persistently higher wages in the host country. The analysis shows that, if migrations are temporary, the optimal migration duration may decrease if the wage differential grows larger. Using micro data for Germany, the second part of the paper provides empirical evidence which is compatible with this hypothesis.     

Investment Decisions,Financial Flows,and Self‐Enforcing Contracts*

This article studies the role of risk sharing in dynamic credit relationships that are secured by physical collateral. It is shown that, when borrowers and lenders cannot commit not to terminate relationships (through default in the first case and liquidation in the second), overinvestment is optimal. Overinvestment facilitates risk sharing in this context: It occurs in expectation of periods in which lenders are unwilling to supply all the funds necessary to achieve complete risk sharing. Typically, overinvestment happens when investment decreases; it slows down the pace at which the capital stock is reduced and therefore results in production smoothing.     

Regulierung, Effizienz und das Anreizdilemma bei Investitionen in intelligente Netze

In this paper, we survey from a theoretical point of view to what extend cost-based and incentive-based regulatory regimes stimulate investments. For the purpose of this analysis, we furthermore differentiate by different efficiency measures, i.e. allocative efficiency, productive efficiency and dynamic efficiency and analyse to what extend each efficiency measure is stimulated by the regulatory regime. Eventually, we analyse to what extend regulatory incentives for network innovation in a smart grid context exist and to what extend different forms of regulation stimulate dynamic efficiency.     

Modelling the Link Between US Inflation and Output: The Importance of the Uncertainty Channel

This article employs an augmented version of the UECCC GARCH specification proposed in Conrad and Karanasos (2010) which allows for lagged in‐mean effects, level effects as well as asymmetries in the conditional variances. In this unified framework, we examine the twelve potential intertemporal relationships among inflation, growth and their respective uncertainties using US data. We find that high inflation is detrimental to output growth both directly and indirectly via the nominal uncertainty. Output growth boosts inflation but mainly indirectly through a reduction in real uncertainty. Our findings highlight how macroeconomic performance affects nominal and real uncertainty in many ways and that the bidirectional relation between inflation and growth works to a large extent indirectly via the uncertainty channel.     

Managing uncertain,complex product development in high‐tech firms: in search of controlled flexibility

This paper investigates ways of managing complexity and uncertainty in R&D simultaneously. Previous research on the subject indicates that these dimensions require different approaches, but these studies tend to provide suggestions either on managing complexity in stable industries or on handling uncertainty in less complex projects. In this paper, the two dimensions are studied simultaneously in three commercial product development projects at a firm that may be viewed as an extreme case of complexity and with multiple dimensions of uncertainty. The paper illustrates that a critical issue in this kind of high‐tech development is the search for and development of approaches that integrate and balance needs for formal organizational control with high levels of project flexibility. Four key elements of such integrated approaches are identified: hybrid formal systems, structured interaction in public arenas, transparent visual communication tools, and a system of participative reflection.     

What makes countries initiate WTO disputes on food-related issues?

This paper analyses relevant determinants for the probability to initiate a dispute on policy measures under the World Trade Organization (WTO) dispute settlement system. The empirical analysis differs from existing assessments by focusing on agro-food-related disputes and provides a more in-depth analysis of specific country and sectoral characteristics not considered in previous studies. Contrary to recent analyses of overall trade disputes, the results show that some determinants such as legal capacity and monetary means are not statistically significant. Own protectionist behaviour, endured protectionism, and the duration of WTO membership, however, could be identified as relevant determinants with the expected direction of impact.     

Integrating art as a trans‐boundary element in a radical innovation framework

Companies have learned that radical innovations (RIs) are a prerequisite to grow organically. However, companies struggle to identify and introduce RIs, as their inherent high uncertainties and novelty challenge established organisations and management routines. To address the first challenge, companies need to take a holistic approach and design a trans‐boundary environment of creativity, trans‐disciplinary and entrepreneurial spirit. This environment attracts and retains visionary people, fosters generation of new opportunities and cultivates adaptability. By adapting evaluation metrics for RI, setting up flexible processes, and promoting trans‐disciplinary exchange, the second challenge can be addressed. Increased research has concentrated on several aspects of RI lately, but so far a combining framework is missing. Our paper bridges this gap by developing an improved theoretical framework, enhancing the existing literature and introducing art as a method to advance trans‐disciplinary interchange. In a case‐study approach, we have applied our framework to the research and development department of Vodafone Research and Development, Germany, as they integrate art methodically in their research and development process. Analysing their RI capabilities, we identify the trans‐disciplinary exchange with artists as a novel initiator and driver of RI, which has not yet been adequately considered.     

Multidimensionales Verfahren zur Bestimmung des Regelleistungsbedarfes unter Berücksichtigung von Unsicherheiten

One of the most crucial constraints in operation of electrical power supply systems is the permanent balance between generation and load. Reserve power is held ready to be able to keep this balance also in case of the occurrence of unpredictable events like power plant outages or inevitable deviations of power injections from their predicted values. At this, the allocation of operating reserves is in the field of conflict between level of reliability and cost effectiveness. The amount of reserve generation capacity required in a control area heavily depends on prediction quality which constitutes the need for high quality predictions. This article is about the influence of prediction quality on the amount of reserve generation capacity required in a control area. The algorithms for the assessment of required reserve generation capacity known from literature use the variation calculus technique to account for the aforementioned unpredictable events and prediction errors. In this article, an extension to a convolution-based method is presented in which the uncertainties of the predictions are expressed using intervals. Each parameter is represented by an independent dimension, assuming statistical independence among them. This allows the distinct analysis of each parameter’s influence on the amount of required reserve generation capacity. In addition, two methods for the visualization of the multi-dimensional results are presented, allowing a comprehensive analysis of the parameters’ influences. Standard distribution functions are used to represent the parameters for the simulation and the results are shown as probability density functions of possible imbalances. Based on forecasts of the development of conventional power plants and regenerative generation in the years 2020, 2030 and 2040, the required control power of the future German transmission system is calculated. Influences and dependencies are identified with the extended convolution-based method.     

Beyond the Urban–Suburban Divide: Urbanization and the Production of the Urban in Zurich North

Starting from current debates on ‘global suburbanism' and ‘postsuburbia', this article explores the changes that the former ‘urban periphery' of Zurich North has experienced in the last three decades. It mobilizes Henri Lefebvre's triadic concept of conceived, perceived and lived space in aid of an analysis of the profound urban transformations that can be observed. The construction of a new tramline serves as a guideline for an analysis of the implementation of new governance arrangements strengthening cross‐border cooperation between individual municipalities and new strategies of cooptation and expertise. This resulted in the production of new urban structures which led to a more densely woven and connected urban fabric primarily providing spaces for the headquarter economy and middle‐class housing. Concomitantly, great efforts have been made to create new public spaces, an urban image and even an urban atmosphere. These have proved at least partially successful, thus promoting a symbolic redefinition of the former urban periphery as a distinctively ‘urban' space. Conventional definitions and concepts no longer suffice to adequately understand such novel urban forms, leading to the conclusion that division into an ‘urban' and a ‘suburban' world is no longer a useful tool for urban analysis.