The long run consequences of unilateral divorce laws on children—evidence from SHARELIFE

Previous research has shown adverse effects of growing up under unilateral divorce laws on long-term outcomes of children. It remains an open question of whether these effects of early childhood conditions arise due to divorce laws raising the likelihood of parental marital disruption or whether unilateral divorce laws also affect children in intact marriages by changing intra-household bargaining. Using recently available data from SHARELIFE for 11 Western European countries, we address this question employing a difference-in-differences approach and controlling for childhood family structure and socioeconomic status. Like previous research, we find adverse effects of growing up under unilateral divorce laws on the well-being of children. This effect remains even when controlling for childhood variables. We conclude that unilateral divorce laws affect children by changing family bargaining in intact marriages.     

Die neue Rolle des Projektmanagements – mit dem richtigen Projektmanagement-Assessment zu Wettbewerbsvorteilen

Companies are facing new challenges. Project management can help to address these challenges. But this requires an extended interpretation of project management. This article presents such an extended interpretation in form of project management as a management approach. On this foundation a continuum of project management is being deducted and the new goals, tasks and methods of project management are outlined. In addition this extended interpretation of project management imposes the responsibility on management to ensure the existence of the required project management competences and the need to bring them alive in daily project business. This usually requires the establishment or further development of situational project management competences on corporate and on individual level. The execution of a project management assessment can identify which project management competences are required and to which extent they are already available in the company. But the extended interpretation of project management also imposes new requirements to the assessment model. Those requirements are being described in this article. Furthermore COACH PM, an exemplary realisation of this new type of assessment model, is being introduced to demonstrate how the application of such an assessment model can improve the company’s capability for self-reflection significantly.     

Measuring power and satisfaction in societies with opinion leaders: an axiomatization

Opinion leaders are actors who have some power over their followers as they are able to influence their followers’ choice of action in certain instances. In van den Brink et al. (Homo Oeconomicus 28:161–185, 2011) we proposed a two-action model for societies with opinion leaders. We introduced a power and a satisfaction score and studied some common properties. In this paper we strengthen two of these properties and present two further properties, which allows us to axiomatize both scores for the case that followers require unanimous action inclinations of their opinion leaders to follow them independently from their own action inclinations.     

Determinanten der Vorstandsvergütung

Using a novel, hand-collected data set covering all German non-financial firms listed in the Prime Standard of FWB (Frankfurt Stock Exchange), we examine determinants of executive compensation in German listed firms. We distinguish three potential determinants: firm characteristics, firm performance, and corporate governance characteristics. While we find that simple firm characteristics like size and industry affiliation together with time effects explain more than 60 % of variation in overall compensation, performance characteristics are economically inconsequential for the explanation of compensation levels. When we distinguish between widely held firms and firms with a large blockholder, we find that the latter grant compensation packages that are smaller, less sensitive to the firm’s stock market performance but more sensitive to the firm’s operating performance. Finally, we confirm that supervisory board characteristics also affect the level of executive compensation in German firms. Overall, our findings suggest that although the corporate governance environment in Germany has changed dramatically during the last decade, German listed firms are still exposed to high agency costs.     

Grave fraudulence in medical device research: a narrative review of the PIN seeding study for the Pinnacle hip system

In 2001, DePuy, a wholly-owned subsidiary of Johnson & Johnson (J&J/DePuy), initiated a seeding study called the “Multi-center, Prospective, Clinical Evaluation of Pinnacle Acetabular Implants in Total Hip Arthroplasty” (PIN Study). J&J/DePuy designed this study to develop new business opportunities during the launch of their Pinnacle Hip System (PHS) and generate survivorship data for marketing. This article, the first review of a seeding trial for a medical device, examines internal company documents relating to the PIN Study; the analysis herein focuses on the integrity of J&J/DePuy’s research practices in conception, implementation, and analysis. J&J/DePuy violated the study protocol and manipulated data; consented participants in violation of standards protecting human subjects; and did not secure Institutional Review Board approval for all study sites. J&J/DePuy used PIN Study results as the “fundamental selling point” for the PHS. Medical device seeding trials are distinct from previously-documented pharmaceutical seeding trials because companies can profit directly from device sales and because these studies may be the first clinical evaluation of the device (as was the case for the PIN Study). Seeding trials are malleable marketing projects, not rigorous scientific studies. Regulatory bodies, physicians, and others should be vigilant for persuasive marketing accounts disguised as science.     

Risk, complexity, and deviations from expected-value maximization: Results of a lottery choice experiment

Varying several parameters of single-stage lottery choice tasks we investigate the question which features of a decision task lead subjects to deviate from maximizing expected monetary value (EV). Despite small differences in EV between the two lotteries in the choice sets, the subjects on average chose the lottery with the higher EV in every task. Risk avoidance occurs, but not consistently over all tasks. Further results are that subjects prefer less complex lotteries over more complex ones, and that risk matters the more the less complex the decision task is.     

Do individual investors learn from their mistakes?

Based on recent empirical evidence which suggests that as investors gain experience, their investment performance improves, we hypothesize that the specific mechanism through which experience translates into better investment returns is closely related to learning from investment mistakes. To test our hypotheses, we use an administrative dataset which covers the trading history of 19,487 individual investors. Our results show that underdiversification and the disposition effect do not decline as investors gain experience. However, we find that experience correlates with less portfolio turnover. We conclude that compared to other investment mistakes, it is relatively easy for individuals to identify and avoid costs related to excessive trading activity. When correlating experience with portfolio returns, we find that as investors gain experience, their portfolio returns improve. A comparison of returns before and after accounting for transaction costs reveals that this effect is related to learning from overtrading.     

Reassessing the link between premarital cohabitation and marital instability

Premarital cohabitation has been found to be positively correlated with the likelihood of marital dissolution in the United States. To reassess this link, I estimate proportional hazard models of marital dissolution for first marriages by using pooled data from the 1988, 1995, and 2002 surveys of the National Survey of Family Growth (NSFG). These results suggest that the positive relationship between premarital cohabitation and marital instability has weakened for more recent birth and marriage cohorts. Using multiple marital outcomes for a person to account for one source of unobserved heterogeneity, panel models suggest that cohabitation is not selective of individuals with higher risk of marital dissolution and may be a stabilizing factor for higher-order marriages. Further research with more recent data is needed to assess whether these results are statistical artifacts caused by data weaknesses in the NSFG.