Abstract：Scale-free issues of complex systems, including scale-free property of complex systems, analysis of power law distribution, the evolving mechanisms for scale-free property, scale-free phenomena of complex systems, and macro-control of scale-free property, are systemically researched in this paper. We emphasize that: ①Generally speaking, scale-free property is one of the intrinsic characteristics of complex systems, which describes their overall extremely uneven asymmetry distributions; ②Various complex systems with power-law distribution are highly heterogeneous only when their scaling exponents are between 2 and 3, which is proved theoretically by the authors; ③The macro-control principle for the scale-free property of the very important complex systems involved in the national economy and the people's livelihood is proposed.
2006, Vol. 24 
