Diversity and Social Network Structure in Collective Decision Making: Evolutionary Perspectives with Agent-Based Simulations

Collective, especially group-based, managerial decision making is crucial in organizations. Using an evolutionary theoretic approach to collective decision making, agent-based simulations were conducted to investigate how human collective decision making would be affected by the agents' diversity in problem understanding and/or behavior in discussion, as well as by their social network structure. Simulation results indicated that groups with consistent problem understanding tended to produce higher utility values of ideas and displayed better decision convergence, but only if there was no group-level bias in collective problem understanding. Simulation results also indicated the importance of balance between selection-oriented (i.e., exploitative) and variation-oriented (i.e., explorative) behaviors in discussion to achieve quality final decisions. Expanding the group size and introducing non-trivial social network structure generally improved the quality of ideas at the cost of decision convergence. Simulations with different social network topologies revealed collective decision making on small-world networks with high local clustering tended to achieve highest decision quality more often than on random or scale-free networks. Implications of this evolutionary theory and simulation approach for future managerial research on collective, group, and multi-level decision making are discussed.Comment: 27 pages, 5 figures, 2 tables; accepted for publication in Complexit

Effects of Network Connectivity and Diversity Distribution on Human Collective Ideation

Human collectives, e.g., teams and organizations, increasingly require participation of members with diverse backgrounds working in networked social environments. However, little is known about how network structure and the diversity of member backgrounds would affect collective processes. Here we conducted three sets of human-subject experiments which involved 617 participants who collaborated anonymously in a collective ideation task on a custom-made online social network platform. We found that spatially clustered collectives with clustered background distribution tended to explore more diverse ideas than in other conditions, whereas collectives with random background distribution consistently generated ideas with the highest utility. We also found that higher network connectivity may improve individuals' overall experience but may not improve the collective performance regarding idea generation, idea diversity, and final idea quality.Comment: 43 pages, 19 figures, 4 table

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Article quality and publication impact via levels of analysis incorporation : An illustration with transformational/charismatic leadership

Calls for the inclusion of levels of analysis in theory building and testing have increased over the last 25 years. Through analysis of 539 published articles we assess the prevalence of incorporation of levels of analysis in theory/hypothesis formulation, measurement, data analysis, and subsequent theory–data alignment (i.e., article quality) within charismatic and transformational leadership research. Additionally, we examine the relationship between incorporation of levels of analysis into research and publication source quality, as reflected by journal impact factors or when not available, estimated journal impact factors. When controlling for the level of analysis within all articles, results revealed that increasing the complexity of the level of analysis (i.e., higher than individual level), increased the likelihood that measurement, analysis and alignment of theory and data would be presented at the appropriate levels of analysis. In contrast, for articles with published impact factors, when controlling for the level of analysis, results revealed that increasing the complexity of the level of analysis (i.e., higher than individual level) decreased the likelihood that measurement, analysis and alignment of theory and data would be presented at the appropriate levels of analysis

Visualizing Collective Idea Generation and Innovation Processes in Social Networks

Collective idea generation and innovation processes are complex and dynamic, involving a large amount of qualitative narrative information that is difficult to monitor, analyze, and visualize using traditional methods. In this study, we developed three new visualization methods for collective idea generation and innovation processes and applied them to data from online social network experiments. The first visualization is the Idea Cloud, which helps monitor collective idea posting activity and intuitively tracks idea clustering and transition. The second visualization is the Idea Geography, which helps understand how the idea space and its utility landscape are structured and how collaboration was performed in that space. The third visualization is the Idea Network, which connects idea dynamics with the social structure of the people who generated them, displaying how social influence among neighbors may have affected collaborative activities and where innovative ideas arose and spread in the social network