Optimal portfolios with a positive lower bound on final wealth

We consider the determination of optimal portfolios under a lower bound on the final wealth. Possible applications range from capital guarantee strategies over life insurance investment where part of the benefit is a guaranteed return on capital to continuous-time mean-variance problems with a strictly positive lower bound. Our solution method consists of transforming the original problem into a portfolio problem without a positive lower bound but a transformed utility function and a modified initial wealth.     

Nadelstichverletzungen: Kleiner Pieks mit großer Wirkung

Arbeitsschutz als Führungsaufgabe - Eine kurze Unachtsamkeit oder unglückliche Verkettung von Ereignissen und schon ist es passiert: Die Kanüle trifft das Pflegepersonal. Aber: Nadelstichverletzungen lassen sich durch die Verwendung sicherer Produkte und Injektionstechniken reduzieren. Dabei ist die Verbesserung des Arbeits- und Gesundheitsschutzes des medizinischen und pflegerischen Personals eine wichtige Aufgabe der Führungskr?fte.     

Conditional performance evaluation for German equity mutual funds

We investigate the conditional performance of a sample of German equity mutual funds over the period from 1994 to 2003 using both the beta-pricing approach and the stochastic discount factor (SDF) framework. On average, mutual funds cannot generate excess returns relative to their benchmark that are large enough to cover their total expenses. Compared to unconditional alphas, fund performance sharply deteriorates when we measure conditional alphas. Given that stock returns are to some extent predictable based on publicly available information, conditional performance evaluation raises the benchmark for active fund managers because it gives them no credit for exploiting readily available information. Underperformance is more pronounced in the SDF framework than in beta-pricing models. The fund performance measures derived from alternative model specifications differ depending on the number of primitive assets taken to calibrate the SDF as well as the number of instrument variables used to scale assets and/or factors.     

A Bibliometric Review of Open Innovation: Setting a Research Agenda

Through an objective, systematic, and comprehensive review of the literature on open innovation (OI), this article identifies gaps in existing research, and provides recommendations on how hitherto unused or underused organizational, management, and marketing theories can be applied to advance the field. This study adopts a novel approach by combining two complementary bibliometric methods of co‐citation analysis and text mining of 321 journal articles on OI that enables a robust empirical analysis of the intellectual streams and key concepts underpinning OI. Results reveal that researchers do not sufficiently draw on theoretical perspectives external to the field to examine multiple facets of OI. Research also seems confined to innovation‐specific journals with its focus restricted to a select few OI issues, thereby exerting limited influence on the wider business community. This study reveals three distinct areas within OI research: (1) firm‐centric aspects of OI, (2) management of OI networks, and (3) role of users and communities in OI. Thus far, studies have predominantly investigated the firm‐centric aspects of OI, with a particular focus on the role of knowledge, technology, and R&D from the innovating firm's perspective, while the other two areas remain relatively under‐researched. Further gaps in the literature emerge that present avenues for future research, namely to: (1) develop a more comprehensive understanding of OI by including diverse perspectives (users, networks, and communities), (2) direct increased attention to OI strategy formulation and implementation, and (3) enhance focus on customer co‐creation and conceptualize “open service innovation.” Marketing (e.g., service‐dominant logic), organizational behavior (e.g., communities of practice), and management (e.g., dynamic capabilities) offer suitable theoretical lenses and/or concepts to address these gaps.     

Pflegeberatung ist Vertrauenssache

M?ngeln in der h?uslichen Pflege pr?ventiv begegnen – Vertrauen ohne Kontrolle, Routine, überforderung oder das Nichtbeachten des Beziehungsgeflechtes zwischen Pflegenden und Gepflegten führt oft zu Problemen. Der Gesetzgeber verpflichtete deshalb die Pflegekassen und Tr?gerverb?nde von ambulanten Pflegeeinrichtungen zur Erarbeitung von Richtlinien und standardisierten Verfahren für die Pflegefachberatung. Leider gibt es bislang keine verbindliche Umsetzung.     

Rationierung: Teufelszeug oder Herausforderung zum Umdenken?

Umgang mit knappen Ressourcen - Das Schreckgespenst der Rationierung macht sich im Gesundheitswesen breit und beunruhigt Patienten, Anbieter von Gesundheitsleistungen und den Gesetzgeber gleicherma?en. Pflegende befürchten, selbst Opfer oder Henkersknechte dieses Ph?nomens zu werden. Sind diese ?ngste begründet? Und – besteht die M?glichkeit zum Gegensteuern? Eine kritische Einsch?tzung von Ralf Gratias.     

Relative concerns of rural-to-urban migrants in China

As their environment changes, migrants constitute an interesting group to study the effect of relative income on subjective well-being. This paper focuses on the huge population of rural-to-urban migrants in China. Using a novel dataset, we find that the well-being of migrants depends on several reference groups: it is negatively affected by the income of other migrants and workers of home regions; in contrast, we identify a positive, ‘signal’ effect vis-à-vis urban workers: larger urban incomes indicate higher income prospects for the migrants. These effects are particularly strong for migrants who wish to settle permanently, decline with years since migrations and change with other characteristics including work conditions and community ties.     

Pricing assets with higher moments: Evidence from the Australian and us stock markets

This paper investigates the importance of higher moments of return distributions in capturing the variation of average stock returns for companies listed in the leading S&P US and Australian indices. We find that Australian stocks are more negatively skewed but less leptokurtic than US stocks. As a result, we find that co-skewness plays a more important role in explaining Australian returns while co-kurtosis is consistently influential for US stock returns. We postulate that the differences in results are related to the underlying firm characteristics of the companies in the two indices, where principally the Australian firms are noticeably smaller than their US counterparts and concentrated in a smaller number industry sectors. This implies that for many smaller exchanges around the world higher moment characteristics displayed by the US market may not be applicable. We also show our results are robust to partly explaining average stock returns in the presence of size, value, and momentum effects.