When people collaborate, they expect more in return than a simple sum of their efforts. This observation is at the heart so-called public goods game, where participants' contributions are multiplied by an $r$ synergy factor before distributed among group members. However, larger could be effective, which can described factor. To elaborate on possible consequences, this study, we introduce model...

Two general kinds of theory (one ecological and one social) have been advanced to explain the fact that primates have larger brains and greater congnitive abilities than other animals. Data on neocortex volume, group size and a number of behavioural ecology variables are used to test between the various theories. Group size is found to be a function of relative neocortical volume, but the ecolo...

People in densely populated environments typically form groups that split and merge. In this paper we track groups of people so as to reflect this formation process and gain efficiency in situations where maintaining the state of individual people would be intractable. We pose the group tracking problem as a recursive multi-hypothesis model selection problem in which we hypothesize over both, t...