Are Groups more Rational than Individuals? A Review of Interactive Decision Making in Groups

Many decisions are interactive; the outcome of one party depends not only on its decisions or on acts of nature but also on the decisions of others. In the present article, we review the literature on decision making made by groups of the past 25 years. Researchers have compared the strategic behavior of groups and individuals in many games: prisoner’s dilemma, dictator, ultimatum, trust, centipede and principal-agent games, among others. Our review suggests that results are quite consistent in revealing that groups behave closer to the game-theoretical assumption of rationality and selfishness than individuals. We conclude by discussing future research avenues in this area.group decision making, interactive decision making, rationality, discontinuity effect

Get Complicated

Conflicts over important moral differences can divide communities and trap people in destructive spirals of enmity that become intractable. But these conflicts can also be managed constructively. Two laboratory studies investigating the underlying social–psychological dynamics of more tractable versus intractable moral conflicts are presented, which tested a core proposition derived from a dynamical systems theory of intractable conflict. It portrays more intractable conflicts as those, which have lost the complexity inherent to more constructive social relations and have collapsed into overly simplified, closed patterns of thinking, feeling, and acting that resist change. Employing our Difficult Conversations Lab paradigm in which participants engage in genuine discussions over moral differences, we found that higher levels of cognitive, emotional, and behavioral complexity were associated with more tractable conversations. Whereas in a pilot study we examined conflicts that naturally became more/less intractable, in our main experiment, high versus low levels of cognitive complexity were induced

An Exploration of Co-Workers’ Group Identification as Moderator of the Leadership-Health Link

This study explores the leadership-health link from a social identity perspective. It focuses on leadership behaviors that seek to form a strong shared social identity (i.e., identity leadership) and the contextual influence of co-workers’ group identification. In a sample of 319 members in 77 workgroups, data supports the indirect link of identity leadership and reduced symptoms of burnout via perceived social support. However, contrary to our expectation, high levels of co-workers’ group identification weakened the relationship of identity leadership and perceived social support. The implications of this finding for the understanding of leadership as a group process are discussed

Predmnijevanje napona naprezanja kod vrućeg sabijanja čelika s CAE NN i hiperboličnom - sinusoidnom jednadžbom

Hot compression experiments are carried out on steel workpieces by means of Gleeble 1500 thermo mechanical simulator in wide range of temperatures 800 °C - 1200 °C with strain rates 0,1 s-1, 1,0 s-1 and 8,0 s-1and true strains of 0,0 to 0,5. Hot flow curves were estimated by means of the CAE neural networks. The methods of constant smoothness parameter and non-constant (ellipsoidal) smoothness parameter were applied. The use of the latter proved more exact (up to 3,4 %) and simpler if we compare it with the existing data for the flow curve prediction of tool steel by BP NN (up to 7 %), as the proposed method yields better results. The activation energy and other parameters in hyperbolic-sine equation were calculated according to the method proposed by McQueen et al. and according to the method recently proposed by Kugler et al. The latter yields better results at predicting the maximum values of hot flow curves.Pomoću termomehaničkog simulatora Gleeble 1500 izvedeni su vrući pokusi sabijanja čeličnih proba u temperaturnom rasponu 800 °C - 1200 °C, brzinom deformacije 0,1 s-1, 1,0 s-1 i 8,0 s-1 i stupnja defor-macije od 0,0 do 0,5. Naprezanja materijala određena su pomoću CAE neuralnih mreža. Rabljene su metode stalnog i nestalnog (elipsoidnog) parametra glatkoće. Upotreba zadnjih pokazala se za točniju (do 3,4 %) i jednostavniju ako ih se usporedi s znanima podacima krivulje naprezanja alatnog čelika metodom BP NN (do 7 %). Aktivacijska metoda i ostali parametri u hiperbolično - sinusoidnoj jednadžbi izračunani su metodom koju predlaže McQueen i ostali te novijom metodom predloženoj od Kuglera i ostalih. Ta zadnja ima bolje rezultate za predmnijevanje maksimalnih vrijednosti krivulja tečenja u vrućem

Analyses of the reasons for the decreased service time of CrN-coated die for aluminy hot extrusion – a case study

Presented study shows that considerable reserves still exist for increasing the service times (lifetimes) of CrN – coated dies for Al hot extrusion. The main reasons for the decreased service times are revealed and explained regarding the selected CrN - coated die for hot extrusion, i.e. why the service time of the coated-die is not in accordance with the wear resistance of the CrN - coating. The shaping of the bearing surface and presence of the scratches, size and amount of nonmetalic inclusions in the die steel, nodular defects in the CrN - coating, as well as thicknesses uniformity of CrN - coatings along the bearing surface, are relevant influential parameters

Band structure of helimagnons in MnSi resolved by inelastic neutron scattering

A magnetic helix realizes a one-dimensional magnetic crystal with a period given by the pitch length $\lambda_h$. Its spin-wave excitations -- the helimagnons -- experience Bragg scattering off this periodicity leading to gaps in the spectrum that inhibit their propagation along the pitch direction. Using high-resolution inelastic neutron scattering the resulting band structure of helimagnons was resolved by preparing a single crystal of MnSi in a single magnetic-helix domain. At least five helimagnon bands could be identified that cover the crossover from flat bands at low energies with helimagnons basically localized along the pitch direction to dispersing bands at higher energies. In the low-energy limit, we find the helimagnon spectrum to be determined by a universal, parameter-free theory. Taking into account corrections to this low-energy theory, quantitative agreement is obtained in the entire energy range studied with the help of a single fitting parameter.Comment: 5 pages, 3 figures; (v2) slight modifications, published versio

Scanning Tunneling Spectroscopy on Single Crystal MgB2

We report on the results of scanning tunneling spectroscopy measurements on single crystals of Mg2. Tunneling was performed both parallel and perpendicular to the crystalline c-axis. In the first case, a single superconducting gap (Delta_pi = 2.2 meV) associated with the pi-band is observed. Tunneling parallel to the ab-plane reveals an additional, larger gap (Delta_sigma ~ 7 meV) originating in the highly two-dimensional sigma-band. Vortex imaging in the pi-band was performed with the field and tunnel current parallel to the c-axis. The vortices have a large core size compared to estimates based on Hc2, and show an absence of localized states in the core. Furthermore, superconductivity between the vortices is rapidly suppressed by an applied field. A comparison to specific heat measurements is performed.Comment: 12 pages, 7 figs. Submitted to Physica

Being on the same page about social rules and norms: Effects of shared relational models on cooperation in work teams

In working teams, each member has an individual understanding of the social rules and norms that underlie social relationships in the team, as well as about what behavior is appropriate and what behavior can be expected from others. What happens if the members of a team are not “on the same page” with respect to these social rules and norms? Drawing on relational models theory, which posits four elemental relational models that people use to coordinate their social interactions, we examined the effects of a common understanding of relational models in teams (i.e., “shared relational models”) on various aspects of cooperative and uncooperative behaviors. We hypothesized that a shared understanding of relational models in a team is positively related to justice perception and negatively related to relationship conflict, which are in turn related to helping behavior and knowledge hiding. We conducted a field study, collecting data from 46 work teams (N = 189 total participants) in various organizations, and found support for all proposed hypotheses. Our findings emphasize the importance of a shared understanding of relational models for (un)cooperative behavior in teams, thereby opening a new door for research on relational models in organizations