The global market for virtual items, characters and currencies was estimated to exceed 2.1 Billion USD in 2007. Selling virtual goods for real money is an increasingly common revenue model not only for online games and virtual worlds, but for social networking sites and other mainstream online services as well. What drives consumer spending on virtual items is an increasingly relevant question,...

Virtual Worlds have become serious business models and thus gained the attention of law professionals. The legal problems arising out of Virtual Worlds have started a discussion which will be summarized in this article. Moreover arguments will be delivered which can be used to protect users of those Virtual Realities.

In the countries surrounding the Mediterranean basin, most of the semi-natural grazing lands are covered by rangelands. Rangelands can be defined as highly heterogeneous natural vegetation communities with high conservation value, growing in harsh environments (poor soils, unfavourable climatic conditions). In the recent socio-economic context, traditional livestock grazing practices that enabl...

Article history: Received 14 November 2005 Received in revised form 24 April 2006 Accepted 26 May 2006 Available online 31 July 2006 Classic rangeland theory advocates stocking rangelands at relatively lowand constant levels. This theory has been labelled inappropriate for savanna rangelands, because savannas are strongly influenced by stochastic processes. Opportunistic strategies that force a...

Industry revenue for online games is surging. A unique phenomenon in this market is the significant volume of trade among game users, who exchange real money for virtual goods that do not exist in the real world. The market of virtual goods has two distinctive characteristics: 1) the resold virtual items normally involve no quality loss since the attributes are digitally defined, and 2) the gam...

We study the problem of allocating a set of indivisible items to players having additive utility functions over the items. We consider allocations in which no player envies the bundle of items allocated to the other players too much. We present a simple proof that deterministic truthful allocations do not minimize envy by characterizing the truthful mechanisms for two players and two items. Als...

In this account of the history of voting-power measurement, we confine ourselves to the concept of a priori voting power. We show how the concept was re-invented several times and how the circumstances in which it was reinvented led to conceptual confusion as to the true meaning of what is being measured. In particular, power-as-influence was conflated with value in the sense of transferable ut...