2,912 research outputs found
How to Measure Group Selection in Real-world Populations
Multilevel selection and the evolution of cooperation are fundamental to the formation of higher-level organisation and the evolution of biocomplexity, but such notions are controversial and poorly understood in natural populations. The theoretic principles of group selection are well developed in idealised models where a population is neatly divided into multiple semi-isolated sub-populations. But since such models can be explained by individual selection given the localised frequency-dependent effects involved, some argue that the group selection concepts offered are, even in the idealised case, redundant and that in natural conditions where groups are not well-defined that a group selection framework is entirely inapplicable. This does not necessarily mean, however, that a natural population is not subject to some interesting localised frequency-dependent effects ā but how could we formally quantify this under realistic conditions? Here we focus on the presence of a Simpsonās Paradox where, although the local proportion of cooperators decreases at all locations, the global proportion of cooperators increases. We illustrate this principle in a simple individual-based model of bacterial biofilm growth and discuss various complicating factors in moving from theory to practice of measuring group selection
A Personal Perspective on a Conceptual Foundation for Information Systems
In this paper, I propose a conceptual foundation for information systems based on three propositions:
P1: Information systems improve an entityās ability to attain its goals
P2: Information systems improve the ability of entities to cooperate on shared goals
P3: Information systems transform entities in intended and unintended ways.
I apply an evolutionary-historical analysis, a variation of historical analysis, to the emergence of humansā major information processing capabilities to trace the development of information systems to establish the propositions. I identify some research questions directly arising from the three propositions and advance a case that these propositions are potentially a sufficient conceptual foundation for IS research
The Essential Skills of Data Modeling
The critical data modeling issue is learning to think like a data modeler. The representation method is a less important concern, because all dialects of these methods capture the same core data. For data modeling teachers, there are two issues. First, what representation method enables quick sketching of models on a board? Second, what method should students use to capture the fine detail for their assignments? Other issues related to teaching data modeling are also discussed, including the argument for intertwining the teaching of data modeling and SQL
Africaās Contributions to Information Systems
Africans created the worldās first major information systems, gesturing and language. Now days, Africa is once again showing leadership in the area of frugal IS
The Efficacy of Group Selection is Increased by Coexistence Dynamics within Groups
Selection on the level of loosely associated groups has been suggested as a route towards the evolution of cooperation between individuals and the subsequent formation of higher-level biological entities. Such group selection explanations remain problematic, however, due to the narrow range of parameters under which they can overturn within-group selection that favours selfish behaviour. In principle, individual selection could act on such parameters so as to strengthen the force of between-group selection and hence increase cooperation and individual fitness, as illustrated in our previous work. However, such a process cannot operate in parameter regions where group selection effects are totally absent, since there would be no selective gradient to follow. One key parameter, which when increased often rapidly causes group selection effects to tend to zero, is initial group size, for when groups are formed randomly then even moderately sized groups lack significant variance in their composition. However, the consequent restriction of any group selection effect to small sized groups is derived from models that assume selfish types will competitively exclude their more cooperative counterparts at within-group equilibrium. In such cases, diversity in the migrant pool can tend to zero and accordingly variance in group composition cannot be generated. In contrast, we show that if within-group dynamics lead to a stable coexistence of selfish and cooperative types, then the range of group sizes showing some effect of group selection is much larger
THE EFFECT OF MEDIUM AND TASK ON DYADIC COMMUNICATION
A controlled laboratory study examined dyadic communication in face-to-face, telephone, and computer mediated text modes using high and low equivocal tasks. The dependent variables were decision time, consensus, change and communication satisfaction. The study failed to support media richness theory. While the findings support the hypothesis that decision time varies as a function of medium, they do not support similar hypotheses for consensus change and communication satisfaction. No support for hypothesized differences in decision time and consensus change as a function of the interaction of medium and task was found. However, there were consistent significant differences in all dependent measures based on task
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