| 1. | Eg . ravenstein , the british statistician , the ancestor who researches flow of population , has said that the move and flow of population signifies survival and progress , while quiescence signifies stagnation and depression 最早研究人的流动的英国统计学家eg .列文斯坦( ravenstein )曾说过,人的迁移与流动意味着生存和进步,而静止则意味着停滞和萧条。 |