Delinquent Networks

Delinquents are embedded in a network of relationships. Each delinquent decides in a non‐cooperative way how much delinquency effort he will exert. We characterize the Nash equilibrium and derive an optimal enforcement policy, called the key‐player policy. We then extend our characterization of optimal single player network removal to optimal group removal, the key group. We also characterize and derive a policy that targets links rather than players. Finally, we endogenize the network connecting delinquents by allowing players to join the labor market instead of committing delinquent offenses. The key‐player policy turns out to be much more complex because it depends on wages and on the structure of the network. (JEL: A14, C72, K42, L14)     

Let's meet up! The role of relational goods in promoting cooperation

The present paper draws on data collected through a Traveler's Dilemma experiment where the possibility of consuming relational goods is introduced by allowing (or forcing) agents to meet after the experiment. It enriches the literature on social distance by comparing the effect of its reduction when it is a voluntary subject's choice and when it is compulsory.We show that the existing interpretations of the effect of social distance reduction cannot explain the differences in agents’ behavior across our experimental treatments. This allows us to give to the theory of social distance an original interpretation based on the concept of relational goods where the possibility to consume relational goods promotes non-selfish behavior.     

Improving physical and mental health in frontline mental health care providers: Yoga-based stress management versus cognitive behavioral stress management

The need for brief, low-cost, easily disseminable, and effective interventions to promote healthy lifestyles is high. This is especially true for mental health providers. The authors developed two studies to compare the impacts of Cognitive Behavioral Stress Management (CBSM) and Yoga-Based Stress Management (YBSM) interventions for health care professionals. Study 1 offered an 8-week YBSM intervention to 37 mental health care participants and collected health data pre- and post. Study 2 offered YBSM and CBSM classes to 40 randomly assigned mental health care providers and collected mental and physical health data at four time points. In Study 1, using t tests, the YBSM intervention affected a number of mental and physical well-being indices pre to post. In Study 2, using linear mixed modeling, YBSM and CBSM groups both improved significantly (p?p?F?=?4.34), physical activity (YBSM increased more, p?F?=?3.47), overall mental health (YBSM increased more, p?F?=?5.32), and secondary traumatic stress (YBSM decreased more, p?F?=?4.89). YBSM and CBSM appear to be useful for health care professionals’ mental and physical health. YBSM demonstrates some benefit above and beyond the extremely well studied and empirically supported CBSM, including increased physical activity, overall mental health, and decreased secondary traumatic stress benefits.     

Informationsüberlastung bei digitaler Zusammenarbeit – Ursachen,Folgen und Interventionsmöglichkeiten

In this article in the journal Gruppe. Interaktion. Organisation (GIO) we analyze current research on influencing factors and consequences of information overload (IO) in team information exchange mediated by modern information and communication technologies (ICT). We consider, which underlying mediating mechanisms cause information overload in team information search and processing, as well as team decision making and communication information, and discuss possible interventions. We focus both on empirical research and on the differentiation between causes, resources and on team level interventions. Based on existing findings we draw implications for future research and practice. In particular we show, how leaders can avoid IO and can contribute to efficient ICT mediated team communication.     

Who's Who in Networks. Wanted: The Key Player

Finite population noncooperative games with linear‐quadratic utilities, where each player decides how much action she exerts, can be interpreted as a network game with local payoff complementarities, together with a globally uniform payoff substitutability component and an own‐concavity effect. For these games, the Nash equilibrium action of each player is proportional to her Bonacich centrality in the network of local complementarities, thus establishing a bridge with the sociology literature on social networks. This Bonacich–Nash linkage implies that aggregate equilibrium increases with network size and density. We then analyze a policy that consists of targeting the key player, that is, the player who, once removed, leads to the optimal change in aggregate activity. We provide a geometric characterization of the key player identified with an intercentrality measure, which takes into account both a player's centrality and her contribution to the centrality of the others.     

Digitalisierung der Arbeit: Konsequenzen für Führung und Zusammenarbeit

In this paper, we focus on the characteristics and requirements of digital leadership and cooperation when teams are working on complex and dynamic project tasks, and cooperation is mediated by modern information and communication technology. Based on current research results we discuss the question, whether the thesis can be supported that leadership of complex digital teamwork can only be successful if leadership functions are delegated to the team and personal leadership is complemented by structural leadership. Despite many ambiguous research results regarding the effects of digital leadership current findings seem to support that more shared leadership in self-managing project teams seems to be helpful for team performance.     

Measuring risk aversion with lists: a new bias

Various experimental procedures aimed at measuring individual risk aversion involve a list of pairs of alternative prospects. We first study the widely used method by Holt and Laury (Am Econ Rev 92(5):1644–1655, 2002), for which we find that the removal of some items from the lists yields a systematic decrease in risk aversion and scrambles the ranking of individuals by risk aversion. This bias, that we call embedding bias, is quite distinct from other confounds that have been previously observed in the use of the HL method. It may be related to empirical phenomena and theoretical developments where better prospects increase risk aversion. Nevertheless, we also find that the more recent elicitation method due to Abdellaoui et al. (Theory Decis 71:63–80, 2011), also based on lists but using only one and the same probability in the list, does not display any statistically significant bias when the corresponding items of the list are removed. Our results suggest that methods other than the popular HL one may be preferable for the measurement of risk aversion.     

Asymmetric exchange between populations differing in habitat quality: A metapopulation study on the citril finch

The citril finch ( Serinus citrinella ) is a Cardueline finch restricted to the high mountains of western Europe. Since 1991 we have captured-recaptured about 6000 birds in two contrasting subpopulations located on the same mountain but separated by 5 km in distance. Citril finches, at the north-facing locality (La Vansa), rely more on Pine trees ( Pinus uncinata ) as their main food source, than birds at the south-facing locality (La Bofia), which rely more on herb seeds, which are of lower energetic content. Birds at La Vansa had higher body mass and fat score than those at La Bofia, suggesting that La Vansa was a site of higher-quality than La Bofia. By the use of a metapopulation approach and multistate models, we found that citril finches at the high-quality locality (La Vansa) showed higher survival rates than those at the low-quality one (La Bofia) (Vansa adults: φ = 0.42 - 0.04, juveniles: φ = 0.34 - 0.05; Bofia adults: φ = 0.35 - 0.04, juveniles: φ = 0.28 - 0.05). Dispersal was also asymmetric and higher for juvenile birds, with movement rates for juvenile citril finches from the low-quality to the higher-quality locality (Bofia to Vansa: é = 0.38 - 0.10) higher than the reverse (Vansa to Bofia: é = 0.09 - 0.03). We also investigated time-specific factors (e.g. meteorological data and fructification rate of Pinus ) as potential predictors of overall mortality and dispersal patterns. The results do not allow strong conclusions regarding the impact of these factors on survival and movement rates. Patterns of movement found in the Citril Finch between localities document a new model for the dispersal of species from low to high quality habitats, which we label of 'sources and pools'. This contrasts with currently accepted models of 'sources and sinks', in which movement is from high to low quality habitats, and 'Ideal Free Distributions', in which there is a balanced dispersal between habitats of different quality.