In this paper we examine the quantitative effects of margin regulation on volatility in asset markets. We consider a general equilibrium infinite-horizon economy with heterogeneous agents and collateral constraints. There are two assets in the economy which can be used as collateral for short-term loans. For the first asset the margin requirement is exogenously regulated while the margin requirement for the second asset is determined endogenously. In our calibrated economy, the presence of collateral constraints leads to strong excess volatility. Thus, a regulation of margin requirements may have stabilizing effects. However, in line with the empirical evidence on margin regulation in U.S. stock markets, we show that changes in the regulation of one class of assets may have only small effects on these assets' return volatility if investors have access to another (unregulated) class of collateralizable assets to take up leverage. In contrast, a countercyclical margin regulation of all asset classes in the economy has a very strong dampening effect on asset return volatility.
We show that the optimal asset allocation for an investor depends crucially on the theory with which the investor is modeled. For the same market data and the same client data different theories lead to different portfolios. The market data we consider is standard asset allocation data. The client data is determined by a standard risk profiling question and the theories we apply are mean-variance analysis, expected utility analysis and cumulative prospect theory.
The book establishes links between regularity and derivative concepts of nonsmooth analysis and studies of solution methods and stability for optimization, complementarity and equilibrium problems. In developing necessary tools, it presents, in particular, (i) an extended analysis of Lipschitz functions and the calculus of their generalized derivatives, including regularity, successive approximation and implicit functions for multivalued mappings, (ii) a unified theory of Lipschitzian critical points in optimization and other variational problems, with relations to reformulations by penalty, barrier and NCP functions, (iii) an analysis of generalized Newton methods based on linear and nonlinear approximations, (iv) the interpretation of hypotheses, generalized derivatives and solution methods in terms of original data and quadratic approximations, (v) a rich collection of instructive examples and exercises. It is written for researchers, graduate students and practitioners in various fields of applied mathematics, engineering, OR and economics, but also for university teachers and advanced students who wish to get insights into problems, potentials and recent developments of this rich and thriving area of nonlinear analysis and optimization.
We discuss conditions for the Aubin property of solutions to perturbed cone constrained programs, by using and refining results given in Klatte-Kummer "Nonsmooth Equations in Optimization", Kluwer, 2002. In particular, we show that constraint nondegeneracy and hence uniqueness of the multiplier is necessary for the Aubin property of the critical point map. Moreover, we give conditions under which the critical point map has the Aubin property if and only if it is locally single-valued and Lipschitz.
Drawing on Pierre Bourdieu’s theory of social practice, this article develops a novel approach to the study of corporate social responsibility (CSR). According to this approach, pro-social activities are conceptualized as social practices that individual managers employ in their efforts to attain social power. Whether such practices are enacted or not depends on (1) the particular features of the social field; (2) the individual managers’ socially shaped dispositions and (3) their stock of different forms of capital. By combining these theoretical concepts, the Bourdieusian approach we develop highlights the interplay between the economic and non-economic motivations that underlie CSR, acknowledging influences both on the micro- and the macro-level, as well as deterministic and voluntaristic aspects of human behaviour.
Both theoretical considerations as well as empirical findings report mixed results on the relationship between sustainability disclosure and sustainability performance. Theoretical considerations are mainly based on legitimacy theory and voluntary disclosure theory. Due to shortcomings of previous studies with regard to the measurement of the main variables, our paper concentrates on new measurement approaches for sustainability disclosure and sustainability performance. Findings from a sample of 50 German and Swiss companies support our methodological approach. In particular, we find empirical evidence that legitimacy theory and voluntary disclosure theory likewise can explain certain aspects of sustainability reporting.
Innovation research increasingly focuses on understanding why and how firms implement new management practices, processes or structures. Emerging in the shadow of research on technological innovation, growing evidence points towards the inter-firm relation as an important locus of innovation. Yet although organizational theory suggests discrete alternative inter-firm coordination mechanisms, the literature on management innovation has thus far treated the inter-firm relation as one broad mode of organizing. This study takes a configurational perspective to identify archetypes of inter-firm relations leading to the implementation of management innovation. Using fuzzy set Qualitative Comparative Analysis (fsQCA) to analyse 56 firm partnerships in China’s biopharmaceutical industry, the empirical evidence identifies four such discrete inter-firm archetypes: organic coalitions, bureaucratic foundations, coalitions of intense interdependency and reciprocal foundations. The results suggest that the type of interdependency, rather than the coordination mechanisms governing inter-firm relations, leads to the implementation of management innovation.
