中文摘要：

为研究自愿性会计政策变更对企业价值的影响这一基本理论问题．以Feltham—Ohlson模型为基础，建立了企业净资产的随时间而演进的分析模型，并将减值准备的计提纳入模型中．通过对模型的分析，发现在一般情况下，企业价值最大化的实现与基于减值准备的会计政策变更无关；无论是否存在自愿性会计政策变更，再融资约束条件的存在都会导致企业投资机会集的缩小，也即会减少企业价值；在再融资约束条件下，企业为了达到融资门槛而采取的减少减值准备计提的自愿性会计政策变更会进一步减小企业的投资机会集，造成企业价值的进一步下降．

英文摘要：

Based on Feltham - Ohlson Model, this paper has set up a model that enterprise net assets change with time and brings the accrual of impairment provision into it. Through an analysis of the model, the authors find the follows ： In general, the realization of maximum of enterprise value has nothing to do with voluntary accounting changes based on impairment provision. Whether there are voluntary accounting changes or not, the refinancing constraints will reduce the IOS, i.e. enterprise value. On the condition of refinancing constraints, that the enterprise adopts voluntary accounting changes of reducing the accrual of impairment provision in order to meet the demand of refinancing will cause the further decline of IOS .i.e. enterprise value.