Informational cascades in the laboratory: Do they occur for the right reasons?

Recently, the theory of informational cascades has been tested in an experiment by L. Anderson and Ch. Holt (American Economic Review, 87 (1997) 847–862) who report that their data support the theory amazingly well. In this paper we report on an experiment designed to find out whether observed cascades are indeed due to rational Bayesian updating. However, we find little support for rational updating. The simple heuristic “follow your own signal” does much better in explaining our data than Bayesian rationality.     

Social Anomie and Racial Segregation in South Africa

The concept of anomie is one of the classics of sociological theory. Developed by scholars such as Emile Durkheim and Robert K. Merton, the concept refers to the absence of clear social norms and values and to a lack of sense of social regulation. However, whereas Merton focused on features of relative deprivation that cause anomie, Durkheim was primarily interested in the link between rapid social change and social anomie. According to the latter, normative regulation is threatened with being undermined and people are likely to lack the social and psychological means for adjustment in times of rapid social change. Drawing on survey data from the South African General Household Survey polled in 2002, the article examines the ethnical differences in levels of social anomie in the South African society. In order to do so, we, first, place the South African levels of anomie into comparative context. In a second step, we look at the race specific levels of anomie. Third, we investigate whether the differences in anomie between the races are related to the still existing socio-economic inequalities or whether race can be regarded as an independent factor that impacts on anomie. Finally we scrutinize to what extent socio-economic factors account for different levels of anomie within the races.     

The Chairman’s Paradox Revisited

This paper re-examines the so-called ‘chairman’s paradox‘ that was first noticed by Farquharson in his path breaking tract on sophisticated voting, Theory of Voting (1969). The Chairman’s paradox is concerned with the case of a three member committee in which a particular player who has a regular and a tie-breaking vote – the ‘chairman’ – not only will do worse in specific instances under the plurality procedure for three alternatives than if he did not have such a vote, but will also do worse overall. That is, the chairman’s a priori probability of success (‘getting what one wants’) for all possible games with linear (strict) preference orders is lower than that of the two regular members. It is demonstrated that this result, which comes about if voters act strategically rather than sincerely, is not as robust as it has been thought to be. By merely replacing the standard assumption of linear preference orders with weak preference orders, which allow for indifference, we can escape from the paradox for the canonical case of three players and three alternatives. With weak preference orders, the a priori success of the chairman is now greater than that of the other two players. We also point to a new paradox of sophisticated voting.     

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.     

Bandwidth selection for kernel density estimation: a review of fully automatic selectors

On the one hand, kernel density estimation has become a common tool for empirical studies in any research area. This goes hand in hand with the fact that this kind of estimator is now provided by many software packages. On the other hand, since about three decades the discussion on bandwidth selection has been going on. Although a good part of the discussion is about nonparametric regression, this parameter choice is by no means less problematic for density estimation. This becomes obvious when reading empirical studies in which practitioners have made use of kernel densities. New contributions typically provide simulations only to show that the own selector outperforms some of the existing methods. We review existing methods and compare them on a set of designs that exhibit few bumps and exponentially falling tails. We concentrate on small and moderate sample sizes because for large ones the differences between consistent methods are often negligible, at least for practitioners. As a byproduct we find that a mixture of simple plug-in and cross-validation methods produces bandwidths with a quite stable performance.     

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.