Additive and Multiplicative Uncertainty Revisited: What Explains the Contrasting Biases?

above the certainty level while for additive uncertainty the price should be lower than the certainty level. This note gives an intuitive explanation for the result after first presenting a parsimonious review of the two models. We also discuss which, if either, of the two models is more realistic. Received December 14, 2001; revised version received July 16, 2002 Published online: April 30, 2003 We thank referees for helpful comments. Ciaran Driver would like to acknowledge the research facilities from ANU, Canberra for their help in writing this paper.     

生态环境的恶化与乡村社会控制--以清代徽州的棚民活动为中心

从明后期开始进入徽州地区的外地棚民，利用当地丰富的自然资源，进行各种经济活动。在当时的社会条件制约下，此类经济活动耗费了大量的资源，破坏了徽州农村的生态环境，损害了地方和国家的利益。针对这一问题，清代徽州乡村社会各种民间力量和官方联合展开了一场声势浩大的驱禁棚民运动，取得了预期效果。