University of Mannheim

About: University of Mannheim is a education organization based out in Mannheim, Germany. It is known for research contribution in the topics: Context (language use) & Politics. The organization has 4448 authors who have published 12918 publications receiving 446557 citations. The organization is also known as: Uni Mannheim & UMA.

The Changing Corporate Governance Paradigm: Implications for Transition and Developing Countries

Abstract: The rapidly growing literature studying the relationship between legal origin, investor protection and finance has stimulated an important debate in academic circles. It has also generated a cottage industry of applied research and strong policy statements. This paper discusses the implications, in particular for developing and transition countries, from this literature. Our general conclusion is that its focus on the plight of small investors is too narrow when applied to these countries. We argue that this group is unlikely to play an important role in most developing and transition countries. External investors may still be crucial, particularly in transition countries, but they are more likely to come in as strategic investors or creditors. The paper also proposes a broader paradigm including other stakeholders and mechanisms of governance in order to better understand the problems facing these countries and generate policy implications that compensate for the weaknesses of capital markets.

Ontology alignment evaluation initiative: six years of experience

Abstract: In the area of semantic technologies, benchmarking and systematic evaluation is not yet as established as in other areas of computer science, e.g., information retrieval. In spite of successful attempts, more effort and experience are required in order to achieve such a level of maturity. In this paper, we report results and lessons learned from the Ontology Alignment Evaluation Initiative (OAEI), a benchmarking initiative for ontology matching. The goal of this work is twofold: on the one hand, we document the state of the art in evaluating ontology matching methods and provide potential participants of the initiative with a better understanding of the design and the underlying principles of the OAEI campaigns. On the other hand, we report experiences gained in this particular area of semantic technologies to potential developers of benchmarking for other kinds of systems. For this purpose, we describe the evaluation design used in the OAEI campaigns in terms of datasets, evaluation criteria and workflows, provide a global view on the results of the campaigns carried out from 2005 to 2010 and discuss upcoming trends, both specific to ontology matching and generally relevant for the evaluation of semantic technologies. Finally, we argue that there is a need for a further automation of benchmarking to shorten the feedback cycle for tool developers.

Customer Prioritization: Does It Pay Off, and How Should It Be Implemented?

Abstract: It seems to be common sense that to increase profits, firms should prioritize customers (i.e., focus their efforts on the most important customers). However, such a strategy might have substantial negative effects on firms' relationships with customers treated at a low priority level. Prior research does not indicate satisfactorily whether and how customer prioritization pays off. Moreover, although customer prioritization may be strongly present in firms' marketing strategies, firms frequently fail to implement such a strategy. Therefore, it is also important to investigate empirically by which means firms can facilitate implementation. The authors address both issues and conduct a cross-industry study with 310 firms from business-to-consumer and business-to-business contexts together with two independent validation samples. The results show that customer prioritization ultimately leads to higher average customer profitability and a higher return on sales because it (1) affects relationships wit...

On the Equivalence of Soft Wavelet Shrinkage, Total Variation Diffusion, Total Variation Regularization, and SIDEs

Abstract: Soft wavelet shrinkage, total variation (TV) diffusion, TV regularization, and a dynamical system called SIDEs are four useful techniques for discontinuity preserving denoising of signals and images. In this paper we investigate under which circumstances these methods are equivalent in the one-dimensional case. First, we prove that Haar wavelet shrinkage on a single scale is equivalent to a single step of space-discrete TV diffusion or regularization of two-pixel pairs. In the translationally invariant case we show that applying cycle spinning to Haar wavelet shrinkage on a single scale can be regarded as an absolutely stable explicit discretization of TV diffusion. We prove that space-discrete TV diffusion and TV regularization are identical and that they are also equivalent to the SIDEs system when a specific force function is chosen. Afterwards, we show that wavelet shrinkage on multiple scales can be regarded as a single step diffusion filtering or regularization of the Laplacian pyramid of the signal. We analyze possibilities to avoid Gibbs-like artifacts for multiscale Haar wavelet shrinkage by scaling the thresholds. Finally, we present experiments where hybrid methods are designed that combine the advantages of wavelets and PDE/variational approaches. These methods are based on iterated shift-invariant wavelet shrinkage at multiple scales with scaled thresholds.

Distinct influx pathways, not calcium load, determine neuronal vulnerability to calcium neurotoxicity

Abstract: Many forms of neurodegeneration are ascribed to excessive cellular Ca 2+ loading (Ca 2+ hypothesis) We examined quantitatively whether factors other than Ca 2+ loading were determinants of excitotoxic neurodegeneration Cell survival, morphology, free intracellular Ca 2+ concentration ([Ca 2+ ] i ), and 45 Ca 2+ accumulation were measured in cultured cortical neurons loaded with known quantities of Ca 2+ through distinct transmembrane pathways triggered by excitatory amino acids, cell membrane depolarization, or Ca 2+ ionophores Contrary to the Ca 2+ hypothesis, the relationships between Ca 2+ load and cell survival, free [Ca 2+ ] i , and Ca 2+ -induced morphological alterations depended primarily on the route of Ca 2+ influx, not the Ca 2+ load Notably, Ca 2+ loading via NMDA receptor channels was toxic, whereas identical Ca 2+ loads incurred through voltage-sensitive Ca 2+ channels were completely innocuous Furthermore, accounting quantitatively for Ca 2+ loading via NMDA receptors uncovered a previously unreported component of L-glutamate neurotoxicity apparently not mediated by ionotropic or metabotropic glutamate receptors It was synergistic with toxicity attributable to glutamate-evoked Ca 2+ loading, and correlated with enhanced cellular ATP depletion This previously unrecognized toxic action of glutamate constituted a chief excitotoxic mechanism under conditions producing submaximal Ca 2+ loading We conclude that (a) Ca 2+ neurotoxicity is a function of the Ca 2+ influx pathway, not Ca 2+ load, and (b) glutamate toxicity may not be restricted to its actions on glutamate receptors