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With the rapid growth of technology in recent years, we are surrounded by or even dependent on the use of technological devices such as smartphones as they are now an indispensable part of our life. Smartphone applications (apps) provide a wide range of utilities such as navigation, entertainment, fitness, etc. To provide such context-sensitive services to users, apps need to access users' data including sensitive ones, which in turn, can potentially lead to privacy invasions. To protect users against potential privacy invasions in such a vulnerable ecosystem, legislation such as the European Union General Data Protection Regulation (EU GDPR) demands best privacy practices. Therefore, app developers are required to make their apps compatible with legal privacy principles enforced by law. However, this is not an easy task for app developers to comprehend purely legal principles to understand what needs to be implemented. Similarly, bridging the gap between legal principles and technical implementations to understand how legal principles need to be implemented is another barrier to develop privacy-friendly apps. To this end, this paper proposes a privacy and security design guide catalog for app developers to assist them in understanding and adopting the most relevant privacy and security principles in the context of smartphone apps. The presented catalog is aimed at mapping the identified legal principles to practical privacy and security solutions that can be implemented by developers to ensure enhanced privacy aligned with existing legislation. Through conducting a case study, it is confirmed that there is a significant gap between what developers are doing in reality and what they promise to do. This paper provides researchers and developers of privacy-related technicalities an overview of the characteristics of existing privacy requirements needed to be implemented in smartphone ecosystems, on which they can base their work.
One striking observation in Parkinson’s disease (PD) is the remarkable gender difference in incidence and prevalence of the disease. Data on gender differences with regard to disease onset, motor and non-motor symptoms, and dopaminergic medication are limited. Furthermore, whether estrogen status affects disease onset and progression of PD is controversially discussed. In this retrospective single center study, we extracted clinical data of 226 ambulatory PD patients and compared age of disease onset, disease stage, motor impairment, non-motor symptoms, and dopaminergic medication between genders. We applied a matched-pairs design to adjust for age and disease duration. To determine the effect of estrogen-related reproductive factors including number of children, age at menarche, and menopause on the age of onset, we applied a standardized questionnaire and performed a regression analysis. The male to female ratio in the present PD cohort was 1.9:1 (147 men vs. 79 women). Male patients showed increased motor impairment than female patients. The levodopa equivalent daily dose was increased by 18.9% in male patients compared to female patients. Matched-pairs analysis confirmed the increased dose of dopaminergic medication in male patients. No differences were observed in age of onset, type of medication, and non-motor symptoms between both groups. Female reproductive factors including number of children, age at menarche, and age at menopause were positively associated with a delay of disease onset up to 30 months. The disease-modifying role of estrogen-related outcome measures warrants further clinical and experimental studies targeting gender differences, specifically hormone-dependent pathways in PD.
Making agriculture sustainable is a global challenge. In the European Union (EU), the Common Agricultural Policy (CAP) is failing with respect to biodiversity, climate, soil, land degradation as well as socio‐economic challenges.
The European Commission's proposal for a CAP post‐2020 provides a scope for enhanced sustainability. However, it also allows Member States to choose low‐ambition implementation pathways. It therefore remains essential to address citizens' demands for sustainable agriculture and rectify systemic weaknesses in the CAP, using the full breadth of available scientific evidence and knowledge.
Concerned about current attempts to dilute the environmental ambition of the future CAP, and the lack of concrete proposals for improving the CAP in the draft of the European Green Deal, we call on the European Parliament, Council and Commission to adopt 10 urgent action points for delivering sustainable food production, biodiversity conservation and climate mitigation.
Knowledge is available to help moving towards evidence‐based, sustainable European agriculture that can benefit people, nature and their joint futures.
The statements made in this article have the broad support of the scientific community, as expressed by above 3,600 signatories to the preprint version of this manuscript. The list can be found here (https://doi.org/10.5281/zenodo.3685632).
A free Plain Language Summary can be found within the Supporting Information of this article.
Perspectives on participation in continuous vocational education training - an interview study
(2020)
In European industrialized countries, a large number of companies in the healthcare, hotel, and catering sectors, as well as in the technology sector, are affected by demographic, political, and technological developments resulting in a greater need of skilled workers with a simultaneous shortage of skilled workers (CEDEFOP, 2015, 2016). Consequently, employers have to address workers who have not been taken into account such as low-skilled workers, workers returning from a career break, people with a migrant background, older people, and jobseekers and train them, in order to guarantee the professionalization of this workforce (Festing and Harsch, 2018). Continuing vocational education and training (CVET) is seen as an indispensable tool; because CVET has advantages for both employers and employees, it helps to increase the productivity of companies (Barrett and O’Connell, 2001), to prevent the widening of socioeconomic disparities (Dieckhoff, 2007), and to open up career opportunities for the workforce (Rubenson and Desjardins, 2009). However, participation rate on CVET seems to differ, depending on institutional factors (such as sector and size of the company) and individual characteristics (such as qualification level, migration background, age and time of absence from work) (e.g., Rubenson and Desjardins, 2009; Wiseman and Parry, 2017). In contrast to previous research, our study aims to provide a holistic view of reasons for and against CVET, combining the different perspectives of employers and (potential) employees. The analysis of reasons and barriers was carried out based on semi-structured interviews. Fifty-seven employers, 73 employees, and 42 jobseekers (potential employees) from the sectors retail, healthcare and social services, hotels and catering, and technology were interviewed. Results point to considerable differences in the reasons and barriers mentioned by the disadvantaged groups. These differences are particularly significant between employees on the one side and employers, as well as jobseekers, on the other side, while the reasons to attend CVET of jobseekers are more similar to those of employers. The results can be used to tailor CVET more closely to the needs of (potential) employees and thus strengthen both the qualification and career opportunities of (potential) employees and the competitiveness and productivity of companies.
Diversity and psychological health issues at the workplace are pressing issues in today’s organizations. However, research linking two fields is scant. To bridge this gap, drawing from team faultline research, social categorization theory, and the job-demands resources model, we propose that perceiving one’s team as fragmented into subgroups increases strain. We further argue that this relationship is mediated by task conflict and relationship conflict and that it is moderated by psychological empowerment and task interdependence. Multilevel structural equation models on a two-wave sample consisting of 536 participants from 107 work teams across various industries and work contexts partially supported the hypotheses: task conflict did indeed mediate the positive relationships between perceived subgroups and emotional exhaustion while relationship conflict did not; effects on stress symptoms were absent. Moreover, contrary to our expectations, neither empowerment, nor task interdependence moderated the mediation. Results indicate that team diversity can constitute a job demand that can affect psychological health. Focusing on the mediating role of task conflict, we offer a preliminary process model to guide future research at the crossroads of diversity and psychological health at work.
Security has become one of the primary factors that cloud customers consider when they select a cloud provider for migrating their data and applications into the Cloud. To this end, the Cloud Security Alliance (CSA) has provided the Consensus Assessment Questionnaire (CAIQ), which consists of a set of questions that providers should answer to document which security controls their cloud offerings support. In this paper, we adopted an empirical approach to investigate whether the CAIQ facilitates the comparison and ranking of the security offered by competitive cloud providers. We conducted an empirical study to investigate if comparing and ranking the security posture of a cloud provider based on CAIQ’s answers is feasible in practice. Since the study revealed that manually comparing and ranking cloud providers based on the CAIQ is too time-consuming, we designed an approach that semi-automates the selection of cloud providers based on CAIQ. The approach uses the providers’ answers to the CAIQ to assign a value to the different security capabilities of cloud providers. Tenants have to prioritize their security requirements. With that input, our approach uses an Analytical Hierarchy Process (AHP) to rank the providers’ security based on their capabilities and the tenants’ requirements. Our implementation shows that this approach is computationally feasible and once the providers’ answers to the CAIQ are assessed, they can be used for multiple CSP selections. To the best of our knowledge this is the first approach for cloud provider selection that provides a way to assess the security posture of a cloud provider in practice.
Nach den Ereignissen in Gaggenau liest und hört man allenthalben von den "rechtlichen Schwierigkeiten", die hinsichtlich Verboten von Redeauftritten ausländischer Politiker bestünden. In Gaggenau hat man originär sicherheitsrechtlich argumentiert: viel zu viele Leute, viel zu kleiner Parkplatz, Chaos vorprogrammiert. Ähnliches nun in Köln: zu großer Aufwand, zu kurzfristig, Chaos vorprogrammiert. Nehmen wir einmal an, es seien im Einzelfall tragfähige Begründungen gewesen. Dann stellt sich zugleich die Frage: Was kann man tun, wenn man den Auftritt eines ausländischen Vertreters untersagen will, obwohl der Parkplatz groß genug und die Polizei ausreichend gegen Ausschreitungen gewappnet ist? ...
Considering the circumstance that literature dealing with the economic performance of agri-food businesses in general, or particularly with the German agricultural sector, mainly deals with strictly agricultural-related theory in order to explain the economic success of agri-food businesses, the present paper aims to extend existing discourses to further areas of thought. Consequently, the characteristics: a) increased size of agribusiness, b) pull-strategies, c) the development of new markets and d) focus on the processing industry, that all correspond to the current picture of the German agricultural sector and are considered to be significantly responsible for recently managing to outpace the French agri-food sector, will be first explained in their success against the background of mainly non-agricultural-related literature. By doing so helpful and rather unnoted perspectives can be contributed to existing discourses. Second, the paper presents scatter plots which portray correlations between a) the added value of agriculture and the regular labor force, b) the added value of agriculture and the number of agricultural holdings and c) the added value of agriculture and the number of enterprises concerning milk consumption. Corresponding scatter plots which show different developments in Germany and France can be related to the findings of the first part of the paper and allow new perspectives in existing discourses as well.
Risk culture during the last 2000 years - from an aleatory society to the illusion of risk control
(2017)
The culture of risk is 2000 years old, although the term “risk” developed much later. The culture of merchants making decisions under uncertainty and taking the individual responsibility for the uncertain future started with the Roman “Aleatory Society”, continued with medieval sea merchants, who made business “ad risicum et fortunam”, and sustained to the culture of entrepreneurs in times of industrialisation and dynamic economic changes in the 18th and 19th century. For all long-term commercial relationships, the culture of honourable merchants with personal decision-making and individual responsibility worked well. The successful development of sciences, statistics and engineering within the last 100 years led to the conjecture that men can “construct” an economical system with a pre-defined “clockwork” behaviour. Since probability distributions could be calculated ex-post, an illusion to control risk ex-ante became a pattern in business and banking. Based on the recent experiences with the financial crisis, a “risk culture” should understand that human “Strength of Knowledge” is limited and the “unknown unknown” can materialise. As all decisions and all commercial agreements are made under uncertainty, the culture of honourable merchants is key to achieve trust in long-term economic relations with individual responsibility, flexibility to adapt and resilience against the unknown.
Die Wettbewerbsfähigkeit der deutschen Wirtschaft steht vor gewaltigen Herausforderungen. Traditionell starke Sektoren wie die Automobilindustrie oder der Maschinenbau befinden sich angesichts disruptiver Veränderungen durch neue Technologien, den Kampf gegen den Klimawandel und veränderte regulatorische Rahmenbedingungen in einer Umbruchphase. Zahlreiche Industriezweige wandeln sich durch den Einsatz von Künstlicher Intelligenz zu „Smart Industries“. Gleichzeitig gewinnt die Kompetenz in Querschnittstechnologien wie Cloud Computing oder Cyber Security an Bedeutung, da diese den effektiven Einsatz von Künstlicher Intelligenz erst ermöglichen. Eine Analyse der Wettbewerbsposition der deutschen Wirtschaft zeigt auf, dass in manchen Zukunftsfeldern ein erheblicher Nachholbedarf besteht.
Auf die Fragen kommt es an: "Woher kommt der Mensch? wo will er hin? – und warum um alles in der Welt ist er da nicht geblieben?" Der Meister zirkulärer Sinnsuche hat als Fragender seine beste Rolle gefunden und damit den postheroischen Typus Mensch erschaffen, der in der Vieldeutigkeit der Welt erleichtert seinen Unfrieden findet: damit, dass Pazifisten Kriege verteidigen, dass die Außerparlamentarischen eine Partei gründen, dass die Konservativen die interessanteren Zeitungen machen und die Komik zur wirksamsten Waffe gegen Dummheit und Schmerz geworden ist. Matthias Beltz hat beiläufig mit Lebensweisheiten und assoziativ aufgetürmtem Scharfsinn nicht nur seine Fragen bewaffnet, in denen gewagte Antworten ihren vitalen Keim austreiben, sondern auch das Misstrauen gesät gegenüber politisch korrekten, nachgeplapperten und smarten Antworten. ...
We investigate the default probability, recovery rates and loss distribution of a portfolio of securitised loans granted to Italian small and medium enterprises (SMEs). To this end, we use loan level data information provided by the European DataWarehouse platform and employ a logistic regression to estimate the company default probability. We include loan-level default probabilities and recovery rates to estimate the loss distribution of the underlying assets. We find that bank securitised loans are less risky, compared to the average bank lending to small and medium enterprises.
Advanced machine learning has achieved extraordinary success in recent years. “Active” operational risk beyond ex post analysis of measured-data machine learning could provide help beyond the regime of traditional statistical analysis when it comes to the “known unknown” or even the “unknown unknown.” While machine learning has been tested successfully in the regime of the “known,” heuristics typically provide better results for an active operational risk management (in the sense of forecasting). However, precursors in existing data can open a chance for machine learning to provide early warnings even for the regime of the “unknown unknown.”
A commentary on Commentary: Aesthetic Pleasure versus Aesthetic Interest: The Two Routes to Aesthetic Liking by Consoli, G. (2017). Front. Psychol. 8:1197. doi: 10.3389/fpsyg.2017.01197
In his commentary on the paper “Aesthetic Pleasure versus Aesthetic Interest: The Two Routes to Aesthetic Liking,” authored by Jan R. Landwehr and myself (Graf and Landwehr, 2017), Consoli (2017) deplores two aspects of our paper. First, an inadequate definition and operationalization of the key constructs aesthetic pleasure, aesthetic interest, and aesthetic liking, respectively aesthetic attractiveness. Second, the conclusions drawn from our empirical studies. While I acknowledge that one may have a different theoretical perspective on aesthetic perception and evaluation, it appears that Consoli's (2017) commentary does not even address the empirical data of our studies but only our theoretical assumptions and definitions. In the following, I will address Consoli's (2016, 2017) arguments in more detail, and I will corroborate our theoretical reasoning with the empirical data of our studies (Graf and Landwehr, 2017).....
Inhibitory interneurons govern virtually all computations in neocortical circuits and are in turn controlled by neuromodulation. While a detailed understanding of the distinct marker expression, physiology, and neuromodulator responses of different interneuron types exists for rodents and recent studies have highlighted the role of specific interneurons in converting rapid neuromodulatory signals into altered sensory processing during locomotion, attention, and associative learning, it remains little understood whether similar mechanisms exist in human neocortex. Here, we use whole-cell recordings combined with agonist application, transgenic mouse lines, in situ hybridization, and unbiased clustering to directly determine these features in human layer 1 interneurons (L1-INs). Our results indicate pronounced nicotinic recruitment of all L1-INs, whereas only a small subset co-expresses the ionotropic HTR3 receptor. In addition to human specializations, we observe two comparable physiologically and genetically distinct L1-IN types in both species, together indicating conserved rapid neuromodulation of human neocortical circuits through layer 1.
Although existing research has established that aesthetic pleasure and aesthetic interest are two distinct positive aesthetic responses, empirical research on aesthetic preferences usually considers only aesthetic liking to capture participants’ aesthetic response. This causes some fundamental contradictions in the literature; some studies find a positive relationship between easy-to-process stimulus characteristics and aesthetic liking, while others suggest a negative relationship. The present research addresses these empirical contradictions by investigating the dual character of aesthetic liking as manifested in both the pleasure and interest components. Based on the Pleasure-Interest Model of Aesthetic Liking (PIA Model; Graf and Landwehr, 2015), two studies investigated the formation of pleasure and interest and their relationship with aesthetic liking responses. Using abstract art as the stimuli, Study 1 employed a 3 (stimulus fluency: low, medium, high) × 2 (processing style: automatic, controlled) × 2 (aesthetic response: pleasure, interest) experimental design to examine the processing dynamics responsible for experiencing aesthetic pleasure versus aesthetic interest. We find that the effect of stimulus fluency on pleasure is mediated by a gut-level fluency experience. Stimulus fluency and interest, by contrast, are related through a process of disfluency reduction, such that disfluent stimuli that grow more fluent due to processing efforts become interesting. The second study employed product designs (bikes, chairs, and lamps) as stimuli and a 2 (fluency: low, high) × 2 (processing style: automatic, controlled) × 3 (product type: bike, chair, lamp) experimental design to examine pleasure and interest as mediators of the relationship between stimulus fluency and design attractiveness. With respect to lamps and chairs, the results suggest that the effect of stimulus fluency on attractiveness is fully mediated by aesthetic pleasure, especially in the automatic processing style. Conversely, disfluent product designs can enhance design attractiveness judgments due to interest when a controlled processing style is adopted.
The purpose of the data presented in this article is to use it in ex post estimations of interest rate decisions by the European Central Bank (ECB), as it is done by Bletzinger and Wieland (2017) [1]. The data is of quarterly frequency from 1999 Q1 until 2013 Q2 and consists of the ECB's policy rate, inflation rate, real output growth and potential output growth in the euro area. To account for forward-looking decision making in the interest rate rule, the data consists of expectations about future inflation and output dynamics. While potential output is constructed based on data from the European Commission's annual macro-economic database, inflation and real output growth are taken from two different sources both provided by the ECB: the Survey of Professional Forecasters and projections made by ECB staff. Careful attention was given to the publication date of the collected data to ensure a real-time dataset only consisting of information which was available to the decision makers at the time of the decision.
Does the rotten child spoil his companion? : spatial peer effects among children in rural India
(2014)
This paper identifies the effect of neighborhood peer groups on childhood skill acquisition using observational data. We incorporate spatial peer interaction, defined as a child's nearest geographical neighbors, into a production function of child cognitive development in Andhra Pradesh, India. Our peer group definition takes the form of networks, whose structure allows us to identify endogenous peer effects and contextual effects separately. We exploit variation over time to avoid confounding correlated with social effects. Our results suggest that spatial peer and neighborhood effects are strongly positively associated with a child's cognitive skill formation. Further, we explore the effect of peer groups in helping to provide insurance against the negative impact of idiosyncratic shocks to child learning. We find that the data reject full risk-sharing, but cannot rule out the existence of partial risk-sharing on behalf of peers. We show that peer effects are robust to different specifications of peer interactions and investigate the sensitivity of our estimates to potential misspecification of the network structure using Monte Carlo experiments.
This paper presents a comprehensive extension of pricing two-dimensional derivatives depending on two barrier constraints. We assume randomness on the covariance matrix as a way of generalizing. We analyse common barrier derivatives, enabling us to study parameter uncertainty and the risk related to the estimation procedure (estimation risk). In particular, we use the distribution of empirical parameters from IBM and EURO STOXX50. The evidence suggests that estimation risk should not be neglected in the context of multidimensional barrier derivatives, as it could cause price differences of up to 70%.
We consider a class of panel tests of the null hypothesis of no cointegration and cointegration. All tests under investigation rely on single-equations estimated by least squares, and they may be residual-based or not. We focus on test statistics computed from regressions with intercept only (i.e., without detrending) and with at least one of the regressors (integrated of order 1) being dominated by a linear time trend. In such a setting, often encountered in practice, the limiting distributions and critical values provided for and applied with the situation “with intercept only” are not correct. It is demonstrated that their usage results in size distortions growing with the panel size N. Moreover, we show which are the appropriate distributions, and how correct critical values can be obtained from the literature.
Two alternative hypotheses – referred to as opportunity- and stigma-based behavior – suggest that the magnitude of the link between unemployment and crime also depends on preexisting local crime levels. In order to analyze conjectured nonlinearities between both variables, we use quantile regressions applied to German district panel data. While both conventional OLS and quantile regressions confirm the positive link between unemployment and crime for property crimes, results for assault differ with respect to the method of estimation. Whereas conventional mean regressions do not show any significant effect (which would confirm the usual result found for violent crimes in the literature), quantile regression reveals that size and importance of the relationship are conditional on the crime rate. The partial effect is significantly positive for moderately low and median quantiles of local assault rates.
We analyze and compare the social, cultural and historical determinants that influence the international competitiveness of China and India. Starting with the discussion why pure economic determinants cannot solely explain a country's competitiveness, we will analyze previous qualitative research and evaluate quantitative data to assess which country has more favorable socio-economic factors influencing its economic performance in the long run.
We study platform design in online markets in which buying involves a (nonmonetary) cost for consumers caused by privacy and security concerns. Firms decide whether to require registration at their website before consumers learn relevant product information. We derive conditions under which a monopoly seller benefits from ex ante registration requirements and demonstrate that the profitability of registration requirements is increased when taking into account the prospect of future purchases or an informational value of consumer registration to the firm. Moreover, we consider the effectiveness of discounts (store credit) as a means to influence the consumers’ registration decision. Finally, we confirm the profitability of ex ante registration requirements in the presence of price competition.
Telecommunications companies traditionally offer several tariffs from which their customers can choose the tariff that best suits their preferences. Yet, customers sometimes make choices that are not optimal for them because they do not minimize their bill for a certain usage amount. We show in this paper that companies should be very concerned about choices in which customers pick tariffs that are too small for them because they lead to a significant increase in customers churn. In contrast, this is not the case if customers choose tariffs that are too big for them. The reason is that in particular flat-rates provide customers with the additional benefit that they guarantee a constant bill amount that consumption can be enjoyed more freely because all costs are already accounted for.
Marketers increasingly use word of mouth to promote products or acquire new customers. But is such companystimulated WOM effective? Are customers who are referred by other customers really worth the effort? A recent study clearly says “yes”. In a study of almost 10,000 accounts at a German bank, the referred customers turned out to be 25 % more profi table than customers acquired by other means. Over a 33-month period, they generated higher profi t margins, were more loyal and showed a higher customer lifetime value. The difference in lifetime value between referred and non-referred customers was most pronounced among younger people and among retail (as opposed to private banking) customers. The reward of € 25 per acquired customer clearly paid off. Given the average difference in customer lifetime value of € 40, this amount implied a return on investment (ROI) of roughly 60 % over a six-year period. The encouraging results of this study, however, do not imply that “viral-for-hire” works in each and every case. Referral programs would be most beneficial for products and services that customers might not appreciate immediately. Products and services that imply some kind of risk would also benefit to a more than average degree from referrals because prospects are likely to feel more confi dent when a trusted person has positive experiences. Companies should consider carefully which prospects to target with referral programs and how large a referral fee to provide.
The success stories of design-oriented companies like Apple, Audi or Nike have put design on the agenda in many marketing departments. Consumers cannot elude the effect of aesthetics and therefore design is a major factor for business success. Typically consumers choose the product with the best design, all other aspects being equal. Only when the interplay of product characteristics, brand and design is carefully coordinated can successful products be created. This requires an integrated approach to design, one which is applied right at the beginning of the value chain. Product development, marketing and design need to work in close cooperation, communicate well and frequently, and collect feedback from the market. Superior aesthetics are always important but should be a top priority in cases where efficiency-oriented Asian competitors are able to offer functionally similar products at much lower prices.
In many markets, design is one of the key factors in determining a product’s success. The present research offers insights into the role of design for the success of cars, and offers procedures to measure the quality of the designs objectively. The authors show that visual design plays a major role in a product’s success in the automobile market. In the study, two visual design aspects were already sufficient to significantly improve traditional sales forecasting models for cars. Visual prototypicality and visual complexity both had a positive impact on sales, and designs that were perceived as both prototypical and complex were the ones that displayed the best results. Most design evaluation used to be based on subjective measures, but the researcher applied a new, objective procedure to measure prototypicality and complexity. While the latter was detected by the disk space needed by the compressed image file, the new approach for measuring prototypicality was even more sophisticated. It relied on the technique of image morphing. Morphing is a technique that allows the construction of a visual synthesis – or average picture – from a number of individual pictures. Once a car morph is developed, one can determine the visual similarity of different car models to the morph in order to obtain its prototypicality. In principle, this procedure can be automated completely, and including a large number of versions is possible. These measures therefore seem suitable for supporting design decision processes in practice.
We study the effects of the recent economic crisis on firms׳ bidding behavior and markups in sealed bid auctions. Using data from Austrian construction procurements, we estimate bidders׳ construction costs within a private value auction model. We find that markups of all bids submitted decrease by 1.5 percentage points in the recent economic crisis, markups of winning bids decrease by 3.3 percentage points. We also find that without the government stimulus package this decrease would have been larger. These two pieces of evidence point to pro-cyclical markups.
Markets are central to modern society, so their failures can have devastating effects. Here, we examine a prominent failure: price bubbles. We propose that bubbles are affected by ethnic homogeneity in the market and can be thwarted by diversity. Using experimental markets in Southeast Asia and North America, we find a marked difference: Market prices fit true values 58% better in diverse markets. In homogenous markets, overpricing is higher and traders’ errors are more correlated than in diverse markets. The findings suggest that price bubbles arise not only from individual errors or financial conditions, but also from the social context of decision making. Informing public discussion, our findings suggest that diversity facilitates friction that enhances deliberation and upends conformity.
Spätestens seit die Europäische Zentralbank (EZB) ihr Ankaufprogramm für Wertpapiere bekannt gegeben hat, ist die Diskussion über die Wirksamkeit dieser Maßnahmen auch in Europa angekommen. Wegen der besonderen institutionellen Umstände des Euroraums – Kauf von Anleihen der einzelnen Nationalstaaten und des Verbots der monetären Finanzierung – reichen die möglichen Nebenwirkungen hierzulande über den rein geldpolitischen Horizont hinaus.
"Ökonomische Modelle und Geschichtswissenschaften gehören zusammen", konstatiert der französische Wissenschaftler Thomas Piketty, dessen Thesen weltweit diskutiert werden, und ergänzt in einem Interview in der "Süddeutschen Zeitung" provokant: "Forscher arbeiten mit hochentwickelten Modellen und anspruchsvoller Mathematik, um Kleinigkeiten zu erklären. Manchmal zeigen diese Modelle auch gar nichts." Der Frankfurter Ökonom Bertram Schefold nimmt die Entwicklung seines Fachs – insbesondere in Frankfurt – unter die Lupe.
The aim of the following paper is to examine the complementarities (and divergences) between the paleoliberal Adam Smith and the ordoliberal Walter Eucken. Following the hypothesis that Smith is among the forerunners and predecessors of Ordoliberalism and Social Market Economy, we try to provide the reader with an insight into the socio-political philosophy of Smith and Eucken pointing at similarities and differences alike. Therefore, we base our examination on a systematic primary source text analysis comparing the books and essays written by Eucken and Smith. The paper tackles these questions in two main steps: The first part highlights Smith's and Eucken's complex and interdependent system of natural liberty. The second section reviews Smith's and Eucken's philosophy of the state.
Eucken's writings are rich in content not only from an (constitutional) economic perspective but also from an economic and business ethics perspective – an often neglected perspective of the reception of German Ordoliberalism in general and the Freiburg School of Economics in particular. The paper gives a first insight into the ethical-normative thinking of Eucken, as one of the main representatives of Ordoliberalism, and explains Eucken’s conception of Social Market Economy as a functioning and humane order as well as Eucken’s Kantian understanding of freedom. To conclude the essay tries to classify Eucken’s Ordoliberalism as a part of the spectrum of modern economic and business ethics.
Wie lässt sich das anthropologische Fundament des Ordoliberalismus und der Sozialen Marktwirtschaft beschreiben? Welche Prämissen liegen ihm zugrunde? Ist ein derartiges Menschenbild überhaupt noch zeitgemäß? Welchen Gefahren ist es ausgesetzt und welche institutionellen Vorkehrungen lassen sich treffen? Diese und andere Fragen stehen im Mittelpunkt des nachfolgenden Essays. Dieser ist dabei wie folgt gegliedert: Das zweite Kapitel analysiert die anthropologischen Grundlagen des Ordoliberalismus. Ein Schwerpunkt liegt dabei auf dem kantischen ‚Programm der Freiheit als Autonomie‘. Das darauf folgende dritte Kapitel thematisiert mögliche Gefahrenpotenziale für eben jenes ordoliberale Menschenbild. Hierbei werden insbesondere die Vermachtung der Wirtschaft und die Instrumentalisierung und Funktionalisierung der Wissenschaft eingehender untersucht. Im vorletzten Kapitel schließlich werden die häufig vorgeschlagenen institutionellen Vorkehrungen kritisch evaluiert. Wichtige Beiträge hierzu stammen aus der Feder von Röpke (Clercs und Nobilitas naturalis) und Hayek (Zwei-Kammern-Verfassungsmodell).
As recent newspaper headlines show the topic of patents/patent laws is still heavily disputed. In this paper I will approach this topic from a theoretical-historical and history of economic thought-perspective. In this regard I will link the patent controversy of the nineteenth century with Walter Eucken’s Ordoliberalism – a German version of neoliberalism. My paper is structured as follows: The second chapter provides the reader with a historical introduction. At the heart of this paragraph are the controversy and discourse on patent laws in nineteenth century Europe as well as the pro and contra arguments presented by the anti-patent/free-trade movement respectively by the advocates of patent protection. The focus of my paper is on the struggle for the protection of inventions and innovations in nineteenth century Germany, since Walter Eucken, main representative of the Freiburg School of Law and Economics, picks up the counter-arguments presented in the national debate and in particular by the Kongress deutscher Volkswirthe. The third chapter deals intensively with the question whether patent laws are just ‘nonsense upon stilts’ from an ordoliberal perspective. Here, Eucken’s arguments against the current patent system are elaborated in great detail. The paper ends with a summary of my main findings.
Zeit seines Lebens beschäftigte sich Goethe mit ökonomischen Theorien; in seinem dichterischen Werk entwarf er wirtschaftliche Visionen, die das späte 19. und das frühe 20. Jahrhundert übersahen. Seine positive Vision des Kapitalismus ist von einer Sittlichkeit durchdrungen, die extreme Formen des Erwerbsstrebens und der Ausbeutung hemmt. Dagegen steht Goethes Schreckensbild eines uns modern erscheinenden Kapitalismus, wie es im »Faust« beschworen wird.
Vielfältige Einschnitte im Rentensystem haben die Bedeutung der privaten Altersvorsorge in den vergangenen Jahren massiv erhöht. Neben Immobilienbesitz, Lebensversicherungen und staatlich geförderten Programmen zur privaten Vorsorge hat sich inzwischen auch die eigenverantwortliche Altersvorsorge mit Wertpapierdepots etabliert, so dass die Anzahl privater Depots in den letzten 25 Jahren von 8,0 auf 27,9 Millionen gestiegen ist. Vor diesem Hintergrund ist die Frage von zentraler Bedeutung, wie gut Anleger ihr Geld investieren.
Kaum eine andere Industrie wurde in den vergangenen beiden Jahrzehnten so massiv durch den Einzug der Informationstechnologie geprägt wie der Wertpapierhandel. Traditionelle Geschäftsmodelle haben sich grundlegend verändert. Das klassische Börsenparkett ist nahezu vollständig elektronischen Handelsplattformen gewichen.
Die Rechnung kommt immer zum Schluss – und sie zu bezahlen, macht in der Regel keine Freude. Wenn wir aber schon eher ungern bezahlen, soll die Zahlungsmethode selbst wenigstens einfach, überall verfügbar und sehr sicher sein. Insbesondere die Sicherheit ist beim Bezahlen im 21. Jahrhundert ein wichtiges Thema, zu dem es interdisziplinäre Forschungsansätze aus Wirtschaftswissenschaften, Informatik und Recht in einem von dynamischer Entwicklung geprägten Umfeld gibt.
We analyze the implications of the governance structure in academic faculties for their recruitment decisions when competing for new researchers. The value to individual members through social interaction within the faculty depends on the average status of their fellow members. In recruitment decisions, incumbent members trade off the effect of entry on average faculty status against alternative uses of the recruitment budget if no entry takes place. We show that the best candidates join the best faculties but that they receive lower wages than some lesser ranking candidates. We also study the allocation of surplus created by the entry of a new faculty member and show that faculties with symmetric status distributions maximize their joint surplus under majority voting.
Der verstärkte Umgang mit Wissen in den Wirtschaftswissenschaften ist in den letzten Jahren in den Fokus der Wissenschaftler geraten. Ausgeblendet wurde dabei größtenteils die Kehrseite von Wissen, die Frage nach dem "Nichtwissen". Das Nichtwissen ist aufgrund der vorherrschenden Auffassung des gesellschaftlichen Bildes mit einer negativen Notation behaftet. Die zunehmende Auseinandersetzung des Nichtwissens in den Geisteswissenschaften bringt die positiven Funktionen zur Geltung. Der vorliegende Artikel zeigt zunächst die erfolgsfördernden Funktionen des Nichtwissens auf und implementiert somit Chancen des Nichtwissens in einem wirtschaftwissenschaftlichen Rahmen. Im Anschluss werden empirische Befunde, resultierend aus einer Befragung, die an der Goethe Universität Frankfurt am Main durchgeführt wurde, präsentiert.
We propose a model of the dynamics of organizational communication. Our model specifies the mechanics by which communication impact is fed back to communication inputs and closes the gap between sender and receiver of messages. We draw on language critique, a branch of language philosophy, and derive joint linguistic actions of interlocutors to explain the emergence and adaptation of communication on the group level. The model is framed by Te'eni's cognitive-affective model of organizational communication.
An information system is more than just the information technology; it is the system that emerges from the complex interactions and relationships between the information technology and the organization. However, what impact information technology has on an organization and how organizational structures and organizational change influence information technology remains an open question. We propose a theory to explain how communication structures emerge and adapt to environmental changes. We operationalize the interplay of information technology and organization as language communities whose members use and develop domain-specific languages for communication. Our theory is anchored in the philosophy of language. In developing it as an emergent perspective, we argue that information systems are self-organizing and that control of this ability is disseminated throughout the system itself, to the members of the language community. Information technology influences the dynamics of this adaptation process as a fundamental constraint leading to perturbations for the information system. We demonstrate how this view is separated from the entanglement in practice perspective and show that this understanding has far-reaching consequences for developing, managing, and examining information systems.
Theory building is not only underdeveloped in IT services management research, but in
general in IS. Given the paradigm shift that comes from the development away from a
networked economy towards a network economy, the lack of spending enough attention to
theorizing in IS becomes even more obvious. In the light of other "megatrends" in IS
research, such as the increasing professionalization and use of statistical methods and the
exploitation of extremely large sets of data (often harvested from social media sites), we
might lose interest in theorizing in the presence of the tremendous amount of available
empirical data. In this position paper, the author advocates that services science researchers
should focus on rigor and relevance in their research approaches.
Vom "Netz-Doktor" bis "Health 2.0" : welche Möglichkeiten das Internet chronisch Kranken bieten kann
(2011)
Jeder fünfte Deutsche ist inzwischen bereits über 65 Jahre, und der demografische Wandel schreitet voran. Mit dem wachsenden Anteil Älterer nimmt auch die Zahl der chronisch Kranken stetig zu. Diese Patienten haben einen besonders hohen Bedarf an aktuellen medizinischen Informationen; das stellt neue Herausforderungen an alle Beteiligten im Gesundheitssystem. Unter dem Stichwort "Health 2.0" untersucht der Wirtschaftsinformatiker Christoph Rosenkranz, welche interaktiven Möglichkeiten das Internet den Betroffenen bisher schon bietet und was es darüber hinaus in Zukunft leisten sollte.
The Dagstuhl Perspectives Workshop "Online Privacy: Towards Informational Self-Determination on the Internet" (11061) has been held in February 6-11, 2011 at Schloss Dagstuhl. 30 participants from academia, public sector, and industry have identified the current status-of-the-art of and challenges for online privacy as well as derived recommendations for improving online privacy. Whereas the Dagstuhl Manifesto of this workshop concludes the results of the working groups and panel discussions, this article presents the talks of this workshop by their abstracts.
Der "Generationenvertrag" der gesetzlichen Rentenversicherung hat die Grenzen seiner Leistungsfähigkeit erreicht. Damit ist die "erste Säule" der Alterssicherung, die auf diesem Umlageverfahren basiert, ins Wanken geraten. Schuld daran ist die zunehmende Überalterung der Gesellschaft, aber auch die anhaltend hohe Arbeitslosigkeit, die zu enormen Beitragsausfällen führt. Schon heute sind die Rentenzahlungen nur noch zu rund 75 Prozent durch die Sozialversicherungsbeiträge der arbeitenden Bevölkerung gedeckt, der Rest muss – ähnlich wie bei den Beamtenpensionen – aus dem allgemeinen Steueraufkommen finanziert werden. Das birgt vor allem für die jungen Beitragszahler substanzielle Risiken. Angesichts dieser Perspektiven sind immer weniger junge Menschen bereit, steigende Rentenbeiträge bei stetig sinkenden Leistungen zu akzeptieren. Kann die kapitalgedeckte Alterssicherung diese Defizite auffangen? Wie lassen sich die vielfältigen Konzepte der privaten Alterssicherung bewerten?
We propose a theory characterizing information systems (IS) as language communities which use and develop domain-specific languages for communication. Our theory is anchored in Language Critique, a branch of philosophy of language. In developing our theory, we draw on Systems Theory and Cybernetics as a theoretical framework. "Organization" of a system is directly related to communication of its sub-systems. "Big systems" are self-organizing and the control of this ability is disseminated throughout the system itself. Therefore, the influence on changes of the system from its outside is limited. Operations intended to change an organization are restricted to indirect approaches. The creation of domain-specific languages by the system itself leads to advantageous communication costs compared to colloquial communication at the price of set-up costs for language communities. Furthermore, we demonstrate how our theoretical constructs help to describe and predict the behavior of IS. Finally, we discuss implications of our theory for further research and IS in general. Keywords: Language Critique, language communities, communication, self-organization, IS research
Immer auf den ersten Rängen : Leibniz-Preis für den Frankfurter Volkswirtschaftler Roman Inderst
(2010)
Wenn es um Superlative geht, dann steht der 40-jährige Prof. Roman Inderst immer ganz oben auf dem Treppchen: jung und schon auf den ersten Rängen unter den Top Ten der europäischen Wirtschaftswissenschaftler. Und am 15. März wurde er auch noch als jüngster unter den zehn Preisträgern mit dem wichtigsten deutschen Forschungspreis, dem mit 2,5 Millionen Euro dotierten Gottfried Wilhelm Leibniz-Preis 2010, ausgezeichnet.
Plattformen für Social Communities im Internet, wie Facebook, StudiVZ und XING, haben in den vergangenen Jahren rasant an Popularität gewonnen. Auf ihnen versammeln sich bereits heute Millionen von Nutzern weltweit. Sie verbinden sich über virtuelle Freundeslisten und tauschen sich über gemeinsame Interessen und Aktivitäten aus. Immer häufger werden dazu auch mobile Endgeräte wie Handys verwendet, erlauben diese doch ständig in Kontakt mit der Community zu bleiben. Allerdings wollen viele Nutzer längst nicht jedem Mitglied einer Community alles preisgeben. Doch wie lässt sich die Privatsphäre in solchen Communities besser schützen? Dieser Frage geht das Forschungsprojekt PICOS nach.
In diesem Beitrag zur Frage nach dem Ausmaß von Einkommensarmut von Familien stehen zwei Aspekte im Mittelpunkt. – Zum einen ist im Vorfeld von Verteilungsanalysen die Art der Einkommensgewichtung in Mehrpersonenhaushalten zu klären. Nach Abwägung verschiedener Ansätze zur Ableitung einer Äquivalenzskala wurde eine Präferenz für ein institutionell orientiertes Gewichtungsschema, approximiert durch die alte OECD-Skala, begründet. – Zum anderen wurde der Einfluss der Frauenerwerbsbeteiligung auf die Einkommenssituation von Familien mit Kindern empirisch untersucht. Von prekären Einkommensverhältnissen und Einkommensarmut sind vor allem Familien mit geringfügig beschäftigter oder nichterwerbstätiger Partnerin sowie Alleinerziehende – Letztere wiederum bei fehlender Erwerbstätigkeit besonders stark – betroffen, wobei in den neuen Ländern die Situation wesentlich brisanter ist als in den alten Ländern. Bei politischen Maßnahmen sollten Erwerbswünsche der Frauen und Bedürfnisse der Familien berücksichtigt werden. Von daher sind Transfers im Rahmen des Familienleistungsausgleichs und die öffentliche Förderung von Kinderbetreuungseinrichtungen nicht als konkurrierende, sondern eher als komplementäre Konzepte zu diskutieren.
The recent success of some alternative trading systems (ATSs) has had a strong impact on the traditional stock exchange industry and many observers expect even more dramatic changes in the future. This paper investigates the nature of competition between stock exchanges and ATSs and argues that the introduction of ATSs weakens the level of competition between market-makers in the traditional exchange...
"Verhaltenswissenschaftliche Theorien oder mikroökonomische Theorie?" - das ist nicht die Frage, wenn es um die Erklärung menschlichen Verhaltens in Organisationengeht. Sie schließen sich nämlich nicht gegenseitig aus, sondern ergänzen sich. Deshalb sollten sie gemeinsam, und zwar in einem integrativen und nicht in einem additiven Sinne zumbesseren Verständnis und zur wirksameren Beeinflussung menschlicher Handlungen in Organisationen genutzt werden. Der vorliegende Aufsatz will dazu und zur Vermeidung bzw. Überwindung verfehlter Frontbildungen einen Beitrag leisten. Die ökonomische Effizienz von Anreizsystemen, die in der Regel nicht direkt beurteilt werden kann, sondern indirekt über adäquate Ersatzkriterien oder -wie hier- über plausible Bedingungen, ist, wie sich schnell erkennenläßt, ein besonders treffliches Objektfürderartige Bemühungen unter marktwirtschaftichen Bedingungen.
Inflation hat in den letzten Jahren weltweit erheblich an Popularität eingebüßt. Galten noch in den 1960er und 1970er Jahren moderate Inflationsraten von 5 bis 10 Prozent als wachstums- und beschäftigungsfördernd, so ist es mittlerweile in Politik und Wissenschaft nahezu unstrittig, dass Inflation vor allem volkswirtschaftliche Kosten verursacht und deshalb Preisstabilität das vorrangige Ziel moderner Geldpolitik sein muss. So sieht insbesondere die in Frankfurt ansässige Europäische Zentralbank (EZB) ihre Hauptaufgabe darin, die jährliche Inflationsrate in der Eurozone unter 2 Prozent zu halten. Klettert die Inflationsrate nur wenige Dezimalpunkte über diesen Zielwert, muss mit Zinserhöhungen und einer restriktiven Geldpolitik der Zentralbank gerechnet werden. Diese Geldpolitik i s t gerechtfertigt, wenn bereits niedrige Inflationsraten messbare realwirtschaftliche Effekte besitzen. Eine Studie der Professur für Empirische Makroökonomie untersucht deshalb den Einfluss von Inflation auf die Variabilität der relativen Preise.
We highlight the implications of combining underwriting services and lending for the choice of underwriters and for competition in the underwriting business. We show that cross-selling can increase underwriters’ incentives, and we explain three phenomena: first, that cross-selling is important for universal banks to enter the investment banking business; second, that cross-selling is particularly attractive for highly leveraged borrowers; third, that less-than-market rates are no prerequisite for cross-selling to benefit a bank’s clients. In our model, cross-selling reduces rents in the underwriting business.
Wie können Unternehmen bei der Auswahl von Bewerbern zukünftig besser zwischen Quantität und Qualität abwägen? Welche Wege sollten Kandidaten bei der Suche nach ihrem Wunscharbeitgeber einschlagen? Fragen, mit denen sich die Frankfurter Wirtschaftsinformatiker beschäftigen. Das Internet hat in den letzten Jahren die Personalbeschaffung erobert: Viele große und mittlere Unternehmen suchen ihr neues Personal inzwischen überwiegend auf elektronischem Weg. So lassen sich nicht nur die Kosten für das Personalmarketing deutlich reduzieren, auch die Rekrutierungszeiten werden kürzer. Doch gleichzeitig sehen sich die Unternehmen einer wachsenden Flut von Bewerbern gegenüber: Stellensuchende nutzen – verstärkt durch den Druck des Arbeitsmarkts – zunehmend die Chance, ihre Bewerbung über das Internet schnell, kostengünstig und an mehrere Unternehmen gleichzeitig elektronisch zu versenden. Um schnell die relevantesten Bewerber für ausgeschriebene Stellen zu identifizieren, benötigen die Unternehmen entsprechende Tools. Das Team um Wolfgang König und Tobias Keim erforscht innovative Lösungen.
Soll Wissen nur wirtschaftliches Wachstum fördern? : Umdenken: Innovation als sozialer Prozess
(2009)
Wissenschaftliche Erkenntnisse sollen sich schnell und gewinnbringend in technologische Neuerungen umsetzen lassen, so dass Wirtschaft und Gesellschaft gleichermaßen davon profitieren können. So lässt sich das vorrangige Ziel der Innovations- und Wissenschaftspolitik umschreiben, wie sie beispielsweise von der Europäischen Union betrieben wird. Doch ist diese lineare Betrachtungsweise überhaupt noch zeitgemäß? Zeigen nicht neue Theorien der Ökonomie, dass dieses einfache Fortschrittsverständnis zu kurz greift? Wie müssen sich die herkömmlichen Politikmuster verändern, um Innovation als sozialen Prozess zu verstehen? Wie könnte eine Innovationspolitik aussehen, die Bildung und Wissenschaft nicht nur als Mittel zum ökonomischen Fortschritt instrumentalisiert? Diese und ähnliche aktuelle Fragen wirft unser Forschungsprojekt "Der Beitrag der Neuen Wachstumstheorie zur Koevolution von Wissenskultur und technischem Fortschritt" im Forschungskolleg "Wissenskultur und gesellschaftlicher Wandel" auf.
Ist der Pflegenotstand unabwendbar? : Über die Zukunft der Pflegeversicherung: Defizite und Lösungen
(2007)
Über die gesetzliche Pflegeversicherung wird seit der Verabschiedung des Gesetzes zur sozialen Absicherung des Risikos der Pflegebedürftigkeit (PflegeVersG oder SGB XI) im April 1994 kontrovers diskutiert. Ganz oben auf der politischen Agenda steht dieses Thema wieder seit der jüngsten Debatte zur Gesundheitsreform. Während die CDU/CSU-regierten Länder für eine private, kapitalgedeckte Zusatzversicherung eintreten, favorisieren SPDLänder eine »Bürgerversicherung« auch für die Pflegeversicherung. ...
Wenn Angehörige die Pflege übernehmen : von Kosten und Nutzen intrafamiliärer Pflegevereinbarungen
(2007)
Ob ein Angehöriger im Alter zu Hause von der Familie versorgt werden kann, hängt von vielen Faktoren ab, nicht nur davon, ob die Familienmitglieder über die nötigen Pflegekenntnisse verfügen, motiviert sind oder ob sie sich moralisch verpflichtet fühlen. Bei der Frage nach den Möglichkeiten der Pflege in der Familie, man spricht auch von »intrafamiliären Pflegearrangements«, müssen auch ökonomische Gesichtspunkte berücksichtigt werden: Wer sich als Pflegebedürftiger entscheidet, keinen ambulanten Pflegedienst zu engagieren oder nicht ins Heim zu gehen, der bevorzugt – ökonomisch gesprochen – die Eigenproduktion in Form der Familienpflege gegenüber dem Kauf professioneller Pflegedienstleistungen von externen Märkten. Welche Gründe haben Familien für die Bevorzugung der intrafamiliären Pflege, welchen Nutzen und welche Kosten berücksichtigen sie bei ihrer (Pflege-)Entscheidung? Um die beobachtbare Stabilität und die möglichen Vorteile der Pflege in Familien und Privathaushalten zu erklären, kann die ökonomische Sicht interessante Aspekte erhellen. Letztere werden in diesem Beitrag mit den Ergebnissen einer schriftlichen Befragung zu den Auswirkungen der Gesetzlichen Pflegeversicherung in Hessen konfrontiert.
Seit Jahren wird von einem Krieg der Generationen fabuliert, der in den kommenden Jahrzehnten ausbrechen werde. Von einer Kündigung des Generationenvertrags in der Gesetzlichen Rentenversicherung ist die Rede, nach dem bisher die laufenden Renten aus den gleichzeitig gezahlten Beiträgen ohne Bildung eines Kapitalstocks finanziert werden (Umlageverfahren). Die Menschen werden zunehmend unsicherer, ob sie noch ein Alterseinkommen erwarten können, das einen Ruhestand ohne große finanzielle Sorgen erlaubt und das sie vor Armut im Alter bewahrt. Gleichzeitig spricht man aber von der Generation der Erben, die in den nächsten ein oder zwei Jahrzehnten Erbschaften in bisher nie gekannter Höhe erhalten werden. Diese Gemengelage bedarf der genaueren Durchleuchtung, um echte von vermeintlichen Problemen unterscheiden zu können.
Die Entscheidung, die »Regelaltersgrenze« von derzeit 65 auf 67 Jahre anzuheben, hat erneut der Debatte Auftrieb verschafft, wie der Übergang von der Erwerbsphase in den Ruhestand sinnvoll zu gestalten ist. Sind die betroffenen Altersjahrgänge noch leistungsfähig genug, um weiter berufstätig zu sein? Wie schätzen Arbeitgeber die Einsatzmöglichkeit älterer Arbeitnehmerinnen und Arbeitnehmer ein? Gibt es genügend Arbeitsplätze, um eine erweiterte Zahl von älteren Erwerbstätigen aufzunehmen? Mindert der spätere Ausstieg der Älteren die Einstiegschancen der Jüngeren? Ist der geplante Aufschub der Regelaltersgrenze lediglich ein »Trick«, um die Rentenabschläge hochzuschrauben?
This paper evaluates the effects of job creation schemes on the participating individuals in Germany. Since previous empirical studies of these measures have been based on relatively small datasets and focussed on East Germany, this is the first study which allows to draw policy-relevant conclusions. The very informative and exhaustive dataset at hand not only justifies the application of a matching estimator but also allows to take account of threefold heterogeneity. The recently developed multiple treatment framework is used to evaluate the effects with respect to regional, individual and programme heterogeneity. The results show considerable differences with respect to these sources of heterogeneity, but the overall finding is very clear. At the end of our observation period, that is two years after the start of the programmes, participants in job creation schemes have a significantly lower success probability on the labour market in comparison to matched non-participants.
Models with multiple equilibria are a popular way to explain currency attacks. Morris and Shin (1998) have shown that, in the context of those models, unique equilibria may prevail once noisy private information is introduced. In this paper, we generalize the results of Morris and Shin to a broader class of probability distributions and show - using the technique of iterated elimination of dominated strategies - that uniqueness will hold, even if we allow for sunspots and individual uncertainty about strategic behavior of other agents. We provide a clear exposition of the logic of this model and we analyse the impact of transparency on the probability of a speculative attack. For the case of uniform distribution of noisy signals, we show that increased transparency of government policy reduces the likelihood of attacks. JEL Classification F 31, D 82
The focus of this article is the analysis of the inflation risk of European real estate securities. Following both a causal and a final understanding of risk, the analysis is twofold. First, to examine the causal influence of inflation on short- and long-term asset returns, different regression approaches are employed based on the methodology of Fama and Schwert (1977). Hedging capacities against expected inflation are found only for German open-end funds. Secondly, different shortfall risk measures are used to study whether an investment in European real estate securities protects against a negative real return at the end of a given investment period.
In contrast to the United States and the United Kingdom, little empirical work exists about the distributional characteristics of appraisalbased real estate returns outside these countries. The purpose of this study is to fill this gap by focusing on Germany. In line with other studies, this paper offers an extensive investigation into the distribution of German real estate returns and compares them with and U.S. and U.K. data in the same period. Furthermore, the comovements with bonds and stocks are also examined. In the core, the distributional characteristics for German real estate are comparable to that for the U.S. and U.K.
U.S. investors hold much less international stock than is optimal according to mean–variance portfolio theory applied to historical data. We investigated whether this home bias can be explained by Bayesian approaches to international asset allocation. In comparison with mean–variance analysis, Bayesian approaches use different techniques for obtaining the set of expected returns by shrinking the sample means toward a reference point that is inferred from economic theory. Applying the Bayesian approaches to the field of international diversification, we found that a substantial home bias can be explained when a U.S. investor has a strong belief in the global mean–variance efficiency of the U.S. market portfolio, and in this article, we show how to quantify the strength of this belief. We also found that one of the Bayesian approaches leads to the same implications for asset allocation as the mean–variance/tracking-error criterion. In both cases, the optimal portfolio is a combination of the U.S. market portfolio and the mean–variance-efficient portfolio with the highest Sharpe ratio.
In this paper, we calculate a transaction–based price index for apartments in Paris (France). The heterogeneous character of real estate is taken into account using an hedonic model. The functional form is specified using a general Box–Cox function. The data basis covers 84 686 transactions of the housing market in 1990:01–1999:12, which is one of the largest samples ever used in comparable studies. Low correlations of the price index with stock and bond indices (first differences) indicate diversification benefits from the inclusion of real estate in a mixed asset portfolio. JEL C43, C51, O18, R20.
This paper is focused on the coordination of order and production policy between buyers and suppliers in supply chains. When a buyer and a supplier of an item work independently, the buyer will place orders based on his economic order quantity (EOQ). However, the buyer s EOQ may not lead to an optimal policy for the supplier. It can be shown that a cooperative batching policy can reduce total cost significantly. Should the buyer have the more powerful position to enforce his EOQ on the supplier, then no incentive exists for him to deviate from his EOQ in order to choose a cooperative batching policy. To provide an incentive to order in quantities suitable to the supplier, the supplier could offer a side payment. One critical assumption made throughout in the literature dealing with incentive schemes to influence buyer s ordering policy is that the supplier has complete information regarding buyer s cost structure. However, this assumption is far from realistic. As a consequence, the buyer has no incentive to report truthfully on his cost structure. Moreover there is an incentive to overstate the total relevant cost in order to obtain as high a side payment as possible. This paper provides a bargaining model with asymmetric information about the buyer s cost structure assuming that the buyer has the bargaining power to enforce his EOQ on the supplier in case of a break-down in negotiations. An algorithm for the determination of an optimal set of contracts which are specifically designed for different cost structures of the buyer, assumed by the supplier, will be presented. This algorithm was implemented in a software application, that supports the supplier in determining the optimal set of contracts.
Die zunehmende Monopolisierung auf dem Markt für Informationsressourcen im akademischen Sektor führte in den vergangenen Jahren zu einer verstärkten Bildung von Bibliothekskonsortien auf der Abnehmerseite, die einen Gegenpol in Form einer Einkaufsgenossenschaft darstellen sollten [McCa02]. Diese Tendenzen lassen sich in verschiedenen Ländern wie etwa in Deutschland, England, der Schweiz und der Niederlande beobachten [Okerso]. In den USA sind Konsortien eher selten zu finden; das größte Konsortium ist hier OHIO-Link (http://www.lib.ohio-state.edu/). In Deutschland richten sich die meisten Konsortien wegen der föderalen Finanzierungsstrukturen regional aus; überregionale bzw. deutschlandweite Konsortien sind derzeit noch selten. Ein Zusammenschluss auf thematischer Grundlage findet derzeit so gut wie gar nicht statt, vielmehr werden möglichst viele Bibliotheken in Konsortien unabhängig von den an den jeweiligen Standorten betriebenen Forschungsschwerpunkten eingebunden [AnDe02]....