Illiquide Assets in der Portfoliooptimierung

When optimizing a portfolio, which comprises liquid as well as illiquid assets, under the constraint of a liquidity requirement, one has to take into account the particular characteristics of illiquid assets. Illiquid assets in this context have the constituting property that they can only be sold as a whole and – if sold on a short term basis – selling leads to losses. Performing the analysis of a single period model in a mean downside risk framework with one liquid and one illiquid asset, significant differences are proven in comparison to the results of an optimization concerning solely liquid assets. For example, although the return on assets is safe in the first scenario, the portfolio value is already risky due to the uncertain liquidity requirement and situations arise where the allocation to both the liquid and the illiquid asset is optimal. Furthermore, when asset returns are uncertain, the expected portfolio value depends on the assets’ variances and can even be increased by positive correlations.     

Gender (In)equality in Internet Pornography: A Content Analysis of Popular Pornographic Internet Videos

Although Internet pornography is widely consumed and researchers have started to investigate its effects, we still know little about its content. This has resulted in contrasting claims about whether Internet pornography depicts gender (in)equality and whether this depiction differs between amateur and professional pornography. We conducted a content analysis of three main dimensions of gender (in)equality (i.e., objectification, power, and violence) in 400 popular pornographic Internet videos from the most visited pornographic Web sites. Objectification was depicted more often for women through instrumentality, but men were more frequently objectified through dehumanization. Regarding power, men and women did not differ in social or professional status, but men were more often shown as dominant and women as submissive during sexual activities. Except for spanking and gagging, violence occurred rather infrequently. Nonconsensual sex was also relatively rare. Overall, amateur pornography contained more gender inequality at the expense of women than professional pornography did.     

Subsidizing wages or supplementing transfers? The politics and ambiguity of in-work benefits

In-work benefits (IWB) have become mainstream social policy programmes in modern welfare states. Aimed at employment promotion as well as poverty reduction, their introduction and expansion have been supported by both centre-right and centre-left governments. However, the article argues that policy positions towards IWB are essentially unstable. Political preferences can alter fast, with the same actors advocating IWB growth at one time and containment at another. In part, this is influenced not only by prevailing socio-economic conditions but also by the institutional shape of IWBs, their interaction with complementary policies, and their inherently ambiguous nature. Characterized by multiple aims, IWBs occasionally offer political opportunities but often create challenges and even confound policymaking. Thus, the understanding of the politics of IWB requires a careful consideration of the particular properties of concrete IWBs and the ways in which they relate to other policy arenas. The article discusses this with reference to relevant debates and reforms in Germany.     

Household‐Level Coastal Adaptation and Its Drivers: A Systematic Case Study Review

Evidence‐based information on household‐level adaptation is an important element of integrated management of vulnerable coastal regions. A growing number of empirical studies deal with household‐level adaptation at the coast in different regions. This article provides a systematic review of these studies. We analyze studies according to how households in different parts of the world are currently adapting, or how they are intending to adapt, and identify explanatory factors for adaptation behavior and intention. We find that households implement a broad range of adaptation measures and that adaptation behavior is explained by individual factors such as socioeconomic and cognitive variables, experience, and perceived responsibilities. Nonpersonal characteristics have also been used to explain adaptation behavior and intention but have not been extensively investigated. Few studies employ qualitative research methods and use inductive approaches as well as models stemming from behavioral economics. Our findings suggest that coastal risk management policies should communicate the efficacy of household‐level adaptation, in addition to information about flood risk, in order to encourage coastal households in their adaptation activities. In this context, we discuss the role of resources and responsibility of households for their adaptation behavior. We describe the lessons learnt and formulate a research agenda on household‐level adaptation to coastal flood risk. In practice, coastal risk management policies should further promote individually driven adaptation by integrating it in adaptation strategies and processes.     

Optimizing the conditional value-at-risk in revenue management

Many service industries use revenue management to balance demand and capacity. The assumption of risk-neutrality lies at the heart of the classical approaches, which aim at maximizing expected revenue. In this paper, we give a comprehensive overview of the existing approaches, most of which were only recently developed, and discuss the need to take risk-averse decision makers into account. We then present a heuristic that maximizes conditional value-at-risk (CVaR). Although CVaR has become increasingly popular in finance and actuarial science due to its beneficial properties, this risk measure has not yet been considered in the context of revenue management. We are able to efficiently solve the optimization problem inherent in CVaR by taking advantage of specific structural properties that allow us to reformulate this optimization problem as a continuous knapsack problem. In order to demonstrate the applicability and robustness of our approach, we conduct a simulation study that shows that the new approach can significantly improve the risk profile in various scenarios.     

Modelling beyond regression functions: an application of multimodal regression to speed–flow data

Summary.  For speed–flow data, which are intensively discussed in transportation science, common nonparametric regression models of the type y = m ( x )+noise turn out to be inadequate since simple functional models cannot capture the essential relationship between the predictor and response. Instead a more general setting is required, allowing for multifunctions rather than functions. The tool proposed is conditional modes estimation which, in the form of local modes, yields several branches that correspond to the local modes. A simple algorithm for computing the branches is derived. This is based on a conditional mean shift algorithm and is shown to work well in the application that is considered.     

Transformational leadership climate: Performance linkages, mechanisms, and boundary conditions at the organizational level

Transformational leadership (TFL) climate describes the degree to which leaders throughout an organization engage in TFL behaviors. In this study, we investigate performance linkages, mechanisms, and boundary conditions of TFL climate at the organizational level of analysis. In a sample of 158 independent organizations, 18,094 employees provided data on TFL climate, positive affective climate, trust climate, and employees' task performance behavior and organizational citizenship behavior. In addition, human resource managers rated overall employee productivity. Study results yielded a pattern of moderated mediation for overall employee productivity and employees' aggregate task performance behavior, in that an organization's TFL climate was indirectly (through positive affective climate) related with these outcome variables under conditions of high trust climate, but not under conditions of low trust climate. Further, we found an organization's TFL climate to indirectly relate with employees' aggregate organizational citizenship behavior through positive affective climate, largely independent of the level of trust climate.     

Quasirentenmodell und Honorare für Abschlussprüfungen in Deutschland – eine empirische Analyse

The model by DeAngelo LE (1981a) Auditor independence, ’Low Balling’, and disclosure regulation. J Acc Econ 3:113–127 suggests, that audit fees do not cover audit costs with the client´s first audit when there is perfect competition in the audit market (low balling). Further, audit fees are supposed to increase with the maturity of the relationship with the client (fee cutting). In order to test the DeAngelo model we perform a multiple regression analysis for the German market of listed clients. The results are: First year audit fees do not significantly differ from audit fees in later periods. Audit fees increase with the maturity of the relationship with the client. Additionally, audit fees are positively associated with non-audit fees and (weakly) with Big4-auditors. These findings partly support the propositions of the DeAngelo models.