Showing papers by "University of Mannheim published in 2004"

Information systems outsourcing: a survey and analysis of the literature

Abstract: In the last fifteen years, academic research on information systems (IS) outsourcing has evolved rapidly. Indeed the field of outsourcing research has grown so fast that there has been scant opportunity for the research community to take a collective breath, and complete a global assessment of research activities to date. This paper seeks to address this need by exploring and synthesizing the academic literature on IS outsourcing. It offers a roadmap of the IS outsourcing literature, highlighting what has been done so far, how the work fits together under a common umbrella, and what the future directions might be.In order to adequately address the immense diversity of research on IS outsourcing and outsourcing in general, we develop a conceptual framework that helps us to categorize the literature. In particular, we look at the research objectives, methods used and theoretical foundations of the papers. In identifying the major research objectives, we view outsourcing as an organizational decision process and adapt Simon's stage model of decision making. This allows us to identify five major sourcing issues, from which at least one is covered by each academic article. These are the questions of why to outsource, what to outsource, which decision process to take, how to implement the sourcing decision, and what is the outcome of the sourcing decision. In analyzing the literature, we identify and structure the main explanatory factors and theoretical relationships within each of these sourcing stages. Based on our discussion of the research objectives, theoretical foundations and research approaches taken in the literature, we show how the various research streams hang together and we come up with a number of implications for research. Moreover, we identify a number of emerging sourcing issues. We believe that research on these "new" phenomena such as offshore outsourcing, application service providing and business process outsourcing would benefit from 'standing on the shoulders' of what has already been accomplished in the field of IS outsourcing.

Informational efficiency of credit default swap and stock markets: The impact of credit rating announcements

Abstract: This paper analyzes the response of stock and credit default swap (CDS) markets to rating announcements made by the three major rating agencies during the period 2000–2002. Applying event study methodology, we examine whether and how strongly these markets respond to rating announcements in terms of abnormal returns and adjusted CDS spread changes. First, we find that both markets not only anticipate rating downgrades, but also reviews for downgrade by all three agencies. Second, a combined analysis of different rating events within and across agencies reveals that reviews for downgrade by Standard & Poor’s and Moody’s exhibit the largest impact on both markets. Third, the magnitude of abnormal performance in both markets is influenced by the level of the old rating, previous rating events and, only in the CDS market, by the pre-event average rating level of all agencies.

The link between salespeople’s job satisfaction and customer satisfaction in a business-to-business context: A dyadic analysis

Abstract: Although it has frequently been argued that the job satisfaction of a company’s employees is an important driver of customer satisfaction, systematic research exploring this link is scarce. The present study investigates this relationship for salespeople in a business-to-business context. The theoretical justification for a positive impact of salespeople’s job satisfaction on customer satisfaction is based on the concept of emotional contagion. The analysis is based on a dyadic data set that involves judgments provided by salespeople and their customers collected across multiple manufacturing and services industries. Results indicate the presence of a positive relationship between salespeople’s job satisfaction and customer satisfaction. Furthermore, the relationship between salespeople’s job satisfaction and customer satisfaction is found to be particularly strong in the case of high frequency of customer interaction, high intensity of customer integration into the value-creating process, and high product/service innovativeness.

Inflammatory bowel disease and smoking. A review of epidemiology, pathophysiology, and therapeutic implications

Abstract: The relationship between smoking behavior and inflammatory bowel disease (IBD) is complex. While Crohn's disease (CD) is associated with smoking and smoking has detrimental effects on the clinical course of the disease, ulcerative colitis (UC) is largely a disease of nonsmokers and former smokers. Furthermore, cigarette smoking may even result in a beneficial influence on the course of ulcerative colitis. The potential mechanisms involved in this dual relationship include changes in humoral and cellular immunity, cytokine and eicosanoid levels, gut motility, permeability, and blood flow, colonic mucus, and oxygen free radicals. Nicotine is assumed to be the active moiety. The differential therapeutic consequences comprise the cessation of smoking in CD and, so far, clinical trials using nicotine in different forms of application for UC. In this article, we review the relationship between cigarette smoking and IBD, considering epidemiological, pathogenetic, and clinical aspects.

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.

The Cassini Cosmic Dust Analyzer

Abstract: The Cassini-Huygens Cosmic Dust Analyzer (CDA) is intended to provide direct observations of dust grains with masses between 10-19 and 10-9 kg in interplanetary space and in the jovian and satumian systems, to investigate their physical, chemical and dynamical properties as functions of the distances to the Sun, to Jupiter and to Saturn and its satellites and rings, to study their interaction with the saturnian rings, satellites and magnetosphere. Chemical composition of interplanetary meteoroids will be compared with asteroidal and cometary dust, as well as with Saturn dust, ejecta from rings and satellites. Ring and satellites phenomena which might be effects of meteoroid impacts will be compared with the interplanetary dust environment. Electrical charges of particulate matter in the magnetosphere and its consequences will be studied, e.g. the effects of the ambient plasma and the magnetic field on the trajectories of dust particles as well as fragmentation of particles due to electrostatic disruption.

The European Bond Markets Under Emu

Abstract: In this paper, we document how in the wake of monetary unification the markets for Euro-area sovereign and private-sector bonds have become increasingly integrated. Issuers and investors alike have come to regard the Euro-area bond market as a single one. Primary and secondary bond markets have become increasingly integrated on a pan-European scale. Issuance of corporate bonds has taken off on an unprecedented scale in continental Europe. In the process, both investors and issuers have reaped the considerable benefits afforded by greater competition in the underwriting of private bonds and auctioning of public ones, and by the greater liquidity of secondary markets. Bond yields have converged dramatically in the transition to EMU. The persistence of small and variable yield differentials for sovereign debt under EMU indicates that Euro-area bonds are still not perfect substitutes. However, to a large extent this does not reflect persistent market segmentation but rather small differentials in fundamental risk. Liquidity differences play at most a minor role, and this role appears to arise partly from their interaction with fundamental risk. The challenges still lying ahead are numerous. They include the unbalance between the German-dominated futures and the underlying cash market; the vulnerability of the cash markets' prices to free-riding and manipulation by large financial institutions; the possibility of joint bond issuance by Euro-area countries; the integration of clearing and settlement systems in the Euro-area bond market, and the participation of new accession countries' issuers to this market.

Local-lag and timewarp: providing consistency for replicated continuous applications

Abstract: In this paper, we investigate how consistency can be established for replicated applications changing their state in reaction to user-initiated operations as well as the passing of time. Typical examples of these applications are networked computer games and distributed virtual environments. We give a formal definition of the terms consistency and correctness for this application class. Based on these definitions, it is shown that an important tradeoff relationship exists between the responsiveness of the application and the appearance of short-term inconsistencies. We propose to exploit the knowledge of this tradeoff by voluntarily decreasing the responsiveness of the application in order to eliminate short-term inconsistencies. This concept is called local-lag. Furthermore, a timewarp scheme is presented that complements local-lag by guaranteeing consistency and correctness for replicated continuous applications. The computational complexity of the timewarp algorithm is determined in theory and practice by examining a simple networked computer game. The timewarp scheme is then compared to the well-known dead-reckoning approach. It is shown that the choice between both schemes is application-dependent.

The Role of Non-Financial Factors in Internal Credit Ratings

Abstract: Internal credit ratings are expected to gain in importance because of their potential use for determining regulatory capital adequacy and banks' increasing focus on the risk-return profile in commercial lending. Whereas the eligibility of financial factors as inputs for internal credit ratings is widely accepted, the role of non-financial factors remains ambiguous. Analyzing credit file data from four major German banks, we find evidence that the combined use of financial and non-financial factors leads to a more accurate prediction of future default events than the single use of each of these factors.

Content and Advertising in the Media: Pay-Tv Versus Free-to-Air

Abstract: We compare the advertising intensity and content of programming in a market with competing media platforms. With pay-tv, media platforms have two sources of revenues, advertising revenues and revenues from viewers. With free-to-air media, platforms receive all revenues from advertising. We show that if viewers strongly dislike advertising, the advertising intensity is greater under free-to-air television. We also show that free-to-air television tends to provide more similar content whereas pay-tv stations differentiate their content. In addition, we compare the welfare properties of the two different schemes.

Does the new immigration require a new theory of intergenerational integration

Abstract: Starting from discussions on the validity of the classical assimilation concept, a general model for the explanation of different structural outcomes of interethnic relations is developed. The core of the model builds on the assumption that different outcomes are the often unintended and situation-logic results of (mis-)investments in and with ethnic and non-ethnic capital. Central initial conditions of the model are group size, social and cultural distances and the availability of social capital. The model specifies the mutual relations between these three constructs. Different variants of intergenerational integration of immigrants can thus be reconstructed as special cases of a general mechanism.

The effect of internet piracy on music sales: cross-section evidence

Abstract: We use a 1998-2002 cross-section dataset to analyze the claim of losses due to internet piracy made by the record industry. The results suggest that internet piracy played a significant role in the decline in music sales during the early days of file-sharing networks.

Hierarchical location service for mobile ad-hoc networks

Abstract: Position-based routing has proven to be a scalable and efficient way for packet routing in mobile ad-hoc networks To enable position-based routing, a node must be able to discover the location of the node it wants to communicate with This task is typically accomplished by a location service In this paper, we propose a novel location service called HLS (Hierarchical Location Service) HLS divides the area covered by the network into a hierarchy of regions The top level region covers the complete network A region is subdivided into several regions of the next lower level until the lowest level is reached We call a lowest level region a cell For a given node A, one specific cell is selected on each level of the hierarchy by means of hash function As A changes its position it transmits position updates to these responsible cells If another node wants to determine the position of A it uses the same hash function to determine the cells that may hold information about the position of A It then proceeds to query the nodes in these cells in the order of the hierarchy until it receives a reply containing the current position of A Because of its hierarchical approach HLS is highly scalable and particularly well suited for networks where communication partners tend to be close to each other Due to the inherent scaling limitations of ad-hoc networks it is very likely that most ad hoc networks will display this property Furthermore HLS is very robust to node mobility and node failures since it uses regions to select location servers and not a chain of mobile nodes as it is the case, eg, for the well known Grid Location Service (GLS) We demonstrate these traits by providing extensive simulation data on the behaviour of HLS in a wide range of scenarios and by using GLS as a benchmark

Last Hired, First Fired? The Unemployment Dynamics of Male Immigrants in Germany

Abstract: This paper explores the unemployment dynamics of various immigrant groups in Germany. Several different groups are compared against the native-born population: guest workers, ethnic Germans, immigrants from the EU-15 or other western industrialized countries, non-EU immigrants and finally second-generation immigrants. Event history techniques are applied to German Socio-Economic Panel data from the second half of the 1990s. The analyses underscore the importance of human capital and labour market segmentation in the employment exclusion of immigrant populations. The study contends that the higher risk of unemployment among guest worker immigrants, more recent newcomers from outside the EU and ethnic Germans is only partially related to their inferior human capital characteristics. In fact it appears largely due to their unfavourable labour market allocation, i.e. their over-representation in occupations and economic branches particularly vulnerable during economic slowdown and restructuring. The analyses also show that unemployed immigrants, with the exception of those coming recently from EU-15 countries and second-generation immigrants, retain their outsider status even if successful in finding employment, being largely channelled into the unskilled labour market

Improving Fast Algebraic Attacks

Abstract: An algebraic attack is a method for cryptanalysis which is based on finding and solving a system of nonlinear equations. Recently, algebraic attacks where found helpful in cryptanalysing LFSR-based stream ciphers. The efficiency of these attacks greatly depends on the degree of the nonlinear equations. At Crypto 2003, Courtois [8] proposed Fast Algebraic Attacks. His main idea is to decrease the degree of the equations using a precomputation algorithm. Unfortunately, the correctness of the precomputation step was neither proven, nor was it obvious.

Introduction: History in Organisation Studies

Abstract: There have been various calls in the literature more recently for engaging with history in the study of organisations and their management.1 They have been joined by a number of studies that have e...

Gender Stereotypes and the Attribution of Leadership Traits: A Cross-Cultural Comparison.

Abstract: In this study, we analyzed cultural variations of managerial gender typing, that is, that managers are perceived as possessing traits that are part of the masculine stereotype. Management students of both sexes from three different countries—Australia, Germany, and India—estimated the percentage to which one of three stimulus groups, that is, executives-in-general (no gender specification), male executives, or female executives, possesses person-orientedand task-oriented leadership traits. Participants also rated the importance of these characteristics for the respective group. Furthermore, another group of participants described themselves regarding the two types of traits and their importance for themselves. Altogether, the results indicate a less traditional view of leadership compared to previous findings, which is very similar in all three countries. Nevertheless, there exists an interculturally shared view of a female-specific leadership competence according to which women possess a higher person orientation than men. The self-descriptions of the female and male management students regarding person- and task-oriented traits were found to be very similar.

Gendering family composition: Sex preferences for children and childbearing behavior in the Nordic countries

Abstract: It has been argued that a society’s gender system may influence parents’ sex preferences for children. If this is true, one should expect to find no evidence of such preferences in countries with a high level of gender equality. In this article, we exploit data from population registers from Denmark, Finland, Norway, and Sweden to examine continuities and changes in parental sex preferences in the Nordic countries during the past three to four decades. First, we do not observe an effect of the sex of the firstborn child on second-birth risks. Second, we detect a distinct preference for at least one child of each sex among parents of two children. For third births, Danish, Norwegian, and Swedish parents seem to develop a preference for having a daughter, while Finns exhibit a signifiant preference for having a son. These findings show that modernization and more equal opportunities for women and men do not necessarily lead to parental gender indifference. On the contrary, they may even result in new sex preferences.

A Bayesian Framework for Multi-cue 3D Object Tracking

Abstract: This paper presents a Bayesian framework for multi-cue 3D object tracking of deformable objects. The proposed spatio-temporal object representation involves a set of distinct linear subspace models or Dynamic Point Distribution Models (DPDMs), which can deal with both continuous and discontinuous appearance changes; the representation is learned fully automatically from training data. The representation is enriched with texture information by means of intensity histograms, which are compared using the Bhattacharyya coefficient. Direct 3D measurement is furthermore provided by a stereo system.

Intraoperative radiotherapy for breast cancer

Abstract: Postoperative radiotherapy, which forms part of breast-conserving therapy, may not need to encompass the whole breast. Apart from the consumption of huge resources and patients' time, postoperative radiotherapy deters many women from receiving the benefits of breast-conserving surgery, forcing them to choose a mastectomy instead. If radiotherapy could be given in the operating theatre immediately after surgery, many of these disadvantages could be overcome. One striking fact about local recurrence after breast-conserving surgery is that most occurs in the area of breast immediately next to the primary tumour; this is despite the finding that two-thirds of mastectomy samples have microscopic tumours distributed throughout the breast, even when radiotherapy is omitted. Thus, only the area adjacent to the tumour may need treatment with radiotherapy. On the basis of this premise, clinical scientists have used new technology to administer radiotherapy to the area at greatest risk of local recurrence, with the aim of completing the whole local treatment in one sitting. In this review, we have elaborated on the rationale and different methods of delivery of intraoperative radiotherapy. If this approach is validated by the results of current randomised trials, it could save time, money, and breasts.

An Economist's Guide to Digital Music

Abstract: In this guide, we discuss the impact of digitalization on the music industry. We rely on market and survey data at the international level as well as expert statements from the industry. The guide investigates recent developments in legal and technological protection of digital music and describes new business models as well as consumers' attitude towards music downloads and audio-streaming. We conclude the guide by a discussion of the evolution of the music industry.

Contention-based forwarding for street scenarios

Abstract: In this paper, we propose to apply Contention-Based Forwarding (CBF) to Vehicular Ad Hoc Networks (VANETs). CBF is a greedy position-based forwarding algorithm that does not require proactive transmission of beacon messages. CBF performance is analyzed using realistic movement patterns of vehicles on a highway. We show by means of simulation that CBF as well as traditional position-based routing (PBR) achieve a delivery rate of almost 100 given that connectivity exists. However, CBF has a much lower forwarding overhead than PBR since PBR can achieve high delivery ratios only by implicitly using a trial-and-error next-hop selection strategy. With CBF, a better total throughput can be achieved. We further discuss several optimizations of CBF for its use in VANETs, in particular a new position-encoding scheme that naturally allows for communication paradigms such as `street geocast` and `street flooding`. The discussions show that CBF can be viewed as a concept for convergence of intelligent flooding, geocast, and multi-hop forwarding in the area of inter-vehicle communication.

Mediators of inflammation in the early and the late phase of allergic rhinitis.

Abstract: Purpose of review This review provides the reader with an overview of the early and the late phase of the immediate allergic reaction. Furthermore, recent publications are presented that could reveal important new insights into the mechanisms of allergic inflammation. Recent findings Recent work on the possible roles of nerve growth factor, nitric oxide synthases, several CC chemokines and other mediators is presented. Summary Allergic rhinitis is characterized by the clinical symptoms of sneezing, itching, rhinorrhea, and nasal congestion. Frequently, these are accompanied by eye, ear and throat symptoms or postnasal drip. The symptoms arise as a result of inflammation induced by IgE-mediated immune response to a specific allergen. Inflammatory mediators are released and cells are activated and recruited to the mucosa. In this review, early and late phase responses of the allergic type I reaction are described, including the different cell types and mediators involved. Special attention is paid to new inflammatory processes to provide the reader with recent information.

Clinical review: Immunomodulatory effects of dopamine in general inflammation

Abstract: Large quantitaties of inflammatory mediators are released during the course of endotoxaemia. These mediators in turn can stimulate the sympathetic nervous system (SNS) to release catecholamines, which ultimately regulate inflammation-associated impairment in tissue perfusion, myocardial impairment and vasodilatation. Treatment of sepsis is based on surgical and/or antibiotic therapy, appropriate fluid management and application of vasoactive catecholamines. With respect to the latter, discussions on the vasopressor of choice are still ongoing. Over the past decade dopamine has been considered the 'first line' vasopressor and is frequently used to improve organ perfusion and blood pressure. However, there is a growing body of evidence that dopamine has deleterious side effects; therefore, its clinical relevance seems to be more and more questionable. Nevertheless, it has not been convincingly demonstrated that other catecholamines are superior to dopamine in this respect. Apart from its haemodynamic action, dopamine can modulate immune responses by influencing the cytokine network. This leads to inhibition of expression of adhesion molecules, inhibition of cytokine and chemokine production, inhibition of neutrophil chemotaxis and disturbed T-cell proliferation. In the present review we summarize our knowledge of the immunomodulatory effects of dopamine, with an emphasis on the mechanisms by which these effects are mediated.