中文摘要：

软件开发工作量估算可以为多项与组织决策和项目管理相关的任务提供有效的支持。根据工作量估算的不同目标，通过对COCOMOⅡ成本驱动因子进行扩充和对国内外最新软件项目数据进行回归分析，建立了一个用于工作量估算的IOP模型。该模型采用统一框架，分别从行业水平、组织水平和项目特征3个层次实现基于规模的软件开发工作量估算，以满足针对软件行业、软件组织和特定软件项目的不同的估算目标，例如项目招标、软件组织不同项目的管理和具体软件项目的管理等。最后，给出了IOP模型应用的若干实例。

英文摘要：

Software development effort estimation can support many requirements and tasks which are involved in organization decisionmaking and project management activities. Based on those multi-purposes, an IOP-model for effort estimation is introduced. The model parameters are extended from COCOMO （constructive cost model） Ⅱ and are calibrated by regression analysis from the latest domestic and international software repository. IOP-model adopts a uniform framework and describes effort-and-size-relationship on three levels ofindustry, organization and project.Its result in each level could explain problems of different hierarchies which software organizations and users focus on, such as： project bidding, multiple project management in the same organization and specific project management. Some sample uses of lOP-model are given at the end.