Concave utility on finite sets

When does a preference relation on a finite set have a concave or a strictly concave utility function? We provide a complete answer. Our proof is an application of the Theorem of the Alternative, and constructs a concave utility if one exists.     

A risk-neutral equilibrium leading to uncertain volatility pricing

We study the formation of derivative prices in an equilibrium between risk-neutral agents with heterogeneous beliefs about the dynamics of the underlying. Under the condition that short-selling is limited, we prove the existence of a unique equilibrium price and show that it incorporates the speculative value of possibly reselling the derivative. This value typically leads to a bubble; that is, the price exceeds the autonomous valuation of any given agent. Mathematically, the equilibrium price operator is of the same nonlinear form that is obtained in single-agent settings with worst-case aversion against model uncertainty. Thus, our equilibrium leads to a novel interpretation of this price.     

Soziale Lage — Was sind die drängendsten Probleme?

Democracy seems to be at risk. People elect populists and autocrats, who offer simple solutions to social problems. Often, these problems are not even real ones but are only perceived as such. Economists have measures to determine which problems are fact-based, but they cannot draw a clear distinction between academic analysis and normative demand. If politics pursues a correction of a market outcome, any normative criteria other than efficiency have to be outlined explicitly. Nevertheless, some authors consider inequality one of the central contemporary social and economic challenges. Marcel Fratzscher emphasises that the solution is not found in more redistribution via taxes and transfers, but rather through greater equality of opportunity and social and educational mobility. Bert Rürup thinks that to stabilise the acceptance of the compulsory pension scheme, the dominance of the equivalence principle should be reduced. Further, the existence of different federal subsidy schemes should be replaced by a fixed federal contribution rate in alignment with the pension expenditures. In an international comparison, the fiscal burden for households with small and mid-level earned incomes is exceptionally high in Germany. In order to reduce this burden, Rürup suggests a contribution-free allowance for the social insurance contributions.     

Stochastic Generational Accounting Applied to Reforms of Dutch Occupational Pensions

This paper examines stochastic or ‘value based’ generational accounting as a method to assess the intergenerational redistributive impact of pension reform. The analysis is applied to three policy changes to the regulation of Dutch occupational pensions during the years 2012 and 2013 that mark the transition from defined benefit pensions to ‘defined ambition’ pension schemes.     

Collaborative Prototyping: Cross‐Fertilization of Knowledge in Prototype‐Driven Problem Solving

This paper presents an inductive study that shows how collaborative prototyping across functional, hierarchical, and organizational boundaries can improve the overall prototyping process. Our combined action research and case study approach provides new insights into how collaborative prototyping can provide a platform for prototype‐driven problem solving in early new product development (NPD). Our findings have important implications for how to facilitate multistakeholder collaboration in prototyping and problem solving, and more generally for how to organize collaborative and open innovation processes. Our analysis reveals two levels of prototyping. Besides the more formal managerial level, we identify the informal designer level, where the actual practice of prototyping takes place. On this level, collaborative prototyping transforms the act of prototyping from an activity belonging exclusively to the domain of design engineers to an activity integral to NPD, with participants from within the organization (different functions and managers) and from outside (consultants and users). In effect, this collapses the discrete steps in the prototyping process (at the managerial level) to an essentially continuous process of iterative problem solving (at the designer level) that is centered around the collaborative prototype, which allows participants to see their suggestions implemented and exposing them to the design constraints. The study, moreover, shows how, at various stages of the prototyping process, the actual prototype was used as a tool for communication or development, thus serving as a platform for the cross‐fertilization of knowledge. In this way, collaborative prototyping leads to a better balance between functionality and usability; it translates usability problems into design changes, and it detects emerging usability problems through active engagement and experimentation. As such, the collaborative prototype acts as a boundary object to represent, understand, and transform knowledge across functional, hierarchical, and organizational boundaries. Our study also identifies some constraints in involving the appropriate stakeholders at the right time. The paper specifically elaborates on the role of users in collaborative prototyping, which is important in order to cover all phases of the problem‐solving cycle but triggers an interesting challenge due to the “reverse empathy” that a user may develop for the design constraints—parallel to the designer empathy for the user context. Finally, our study shows that despite the continuous nature of the (designer) practice of prototyping, there are certain windows of opportunities (at the managerial level) during which the collaborative prototyping approach actually leads to changes in the product design.     

Leveraging External Sources of Innovation: A Review of Research on Open Innovation

This paper reviews research on open innovation that considers how and why firms commercialize external sources of innovations. It examines both the “outside‐in” and “coupled” modes of open innovation. From an analysis of prior research on how firms leverage external sources of innovation, it suggests a four‐phase model in which a linear process—(1) obtaining, (2) integrating, and (3) commercializing external innovations—is combined with (4) interaction between the firm and its collaborators. This model is used to classify papers taken from the top 25 innovation journals, complemented by highly cited work beyond those journals. A review of 291 open innovation‐related publications from these sources shows that the majority of these articles indeed address elements of this inbound open innovation process model. Specifically, it finds that researchers have front‐loaded their examination of the leveraging process, with an emphasis on obtaining innovations from external sources. However, there is a relative dearth of research related to integrating and commercializing these innovations. Research on obtaining innovations includes searching, enabling, filtering, and acquiring—each category with its own specific set of mechanisms and conditions. Integrating innovations has been mostly studied from an absorptive capacity perspective, with less attention given to the impact of competencies and culture (including “not invented here”). Commercializing innovations puts the most emphasis on how external innovations create value rather than how firms capture value from those innovations. Finally, the interaction phase considers both feedback for the linear process and reciprocal innovation processes such as cocreation, network collaboration, and community innovation. This review and synthesis suggests several gaps in prior research. One is a tendency to ignore the importance of business models, despite their central role in distinguishing open innovation from earlier research on interorganizational collaboration in innovation. Another gap is a tendency in open innovation to use “innovation” in a way inconsistent with earlier definitions in innovation management. The paper concludes with recommendations for future research that include examining the end‐to‐end innovation commercialization process, and studying the moderators and limits of leveraging external sources of innovation.     

Citizen participation in public administration: investigating open government for social innovation

In recent years, public sector organizations have increasingly focused on citizen contribution by adopting instruments known from open innovation. By collaborating with the periphery and leveraging external knowledge, government institutions initiate social innovation and stimulate a positive change for society. This article examines the involvement of citizens in an ideation platform initiated by a local government and investigates the motivations affecting participation intensity. Drawing on self‐determination theory, we analyze what motivates citizens to participate in an open government platform and how these motivations influence participation quantity. Based on a survey among platform users and the analysis of usage data from the platform operator, we find that motivations of citizen participation in public administration greatly vary across forms of participation. Whereas, intrinsic motivation is positively associated with producing and consuming platform content, external and introjected regulation negatively relate to individuals’ active contribution. At the same time, external regulation is positively associated with evaluation behavior.     

Military casualties and exchange rates during the First World War: did the Eastern Front matter?

Although the First World War was ultimately decided in the west, historians have emphasized the importance of the often ‘forgotten’ Eastern Front in understanding its complex evolution. This article examines the perception of contemporary foreign exchange traders concerning the relative importance of the Eastern Front over time. Using a newly compiled dataset on prisoners of war and on soldiers killed and wounded, we show that traders were concerned with casualties on both fronts, recognizing the significance of the two‐front war in the early war years. From the autumn of 1916 onwards, traders seemed to believe the key to winning the war lay in the west only.     

Reforming the Taxation of Multijurisdictional Enterprises in Europe

In 2001, the European Commission proposed replacing the currentsystem of taxation of multinational companies by the taxationof a consolidated base, computed at the level of all the Europeanentities of a multinational enterprise, and then distributedfor taxation purposes among the various jurisdictions in whichthese entities operate, according to pre-established criteria.In this article, we propose a discussion, especially focusingon two related issues, the choice of the formula and the compositionof the consolidating area—either the entire European Union(EU) or some Member States within an Enhanced Cooperation Agreement—,as well as on their impact on the size and distribution of taxrevenue and economic activity, and on the intensity of tax competition.Our tentative policy conclusion is that the reform deservessupport provided that (i) the formula puts emphasis on criteriathat the firm may not too easily manipulate, (ii) the activitiesof the multijurisdictional enterprise are enough mobile, (iii)the consolidation is made compulsory within the consolidatingarea and (iv) the consolidating area protects its capacity toactually levy tax by adopting a crediting system vis-à-visthe rest of the world. (JEL code: H32, H73, H87)