Aggregation behaviour is the tendency for animals to group together, which may have important consequences on individual fitness. We used a combination of experimental and simulation approaches to study how genetic variation and social environment interact to influence aggregation dynamics in Drosophila To do this, we used two different natural lines of Drosophila that arise from a polymorphism...

Social Choice Theory (SCT), and the study of collective methods for decision making in general, have received a lot of attention in the AI community in recent years. The reasons for this focus are clear: SCT provides tools for the analysis of collective choices of groups of agents, and as such is of immediate relevance to the study of multiagent systems. At the same time, studies in AI have led...

Social dynamics explaining communication among individuals and social relationships represent a major field of investigation in the current scenario of online social network research, whose importance and impact in everyday life is growing at unprecedented rate. This work reports our quantitative assessment of so-called strength of weak ties theory, foreseen by Granovetter’s seminal studies, ap...

The aggregation of individual judgments over interrelated propositions is a newly arising …eld of social choice theory. I introduce several independence conditions on judgment aggregation rules, each of which protects against a speci…c type of manipulation by agenda setters or voters. I derive impossibility theorems whereby these independence conditions are incompatible with certain minimal req...

We address continuously processing an aggregation join query over data streams. Queries of this type involve both join and aggregation operations, with windows specified on join input streams. To our knowledge, the existing researches address join query optimization and aggregation query optimization as separate problems. Our observation, however, is that by putting them within the same scope o...

Judgment aggregation theory studies how to amalgamate individual opinions on a set of logically related issues into a set of collective opinions. Aggregation rules proposed in the literature are sparse. All proposed rules consider only two-valued judgments, thus imposing the strong requirement that an agent cannot abstain from giving judgments on any of the issues. All proposed rules are also i...

Some previous research on the contextual causes of individual political participation has argued that increasing community heterogeneity increases political participation; while other researchers have claimed the opposite: that increasing community homogeneity (decreasing heterogeneity) increases participation. These theories use the different mechanisms of conflict and improved social networks...