The virtual property has three nature of the property which are utility, scarcity and availability. The virtual property is in legal owned by players.
它具有财产的三个属性：效用性、稀缺性、可支配性的，是属于玩家所有的一种具有价值的财产。
2
With the help of mathematical model, the paper employs the concept of external effect in economics and its relevant theory to explore the effects of foreign players on league utility.