应用统计过程控制图监控项目的工期和成本
Application of Statistical Progress Control Chart to Monitor Project Duration and Cost

挣值管理(Earned Value Management, EVM)和挣得工期管理(Earned Duration Management, EDM)是监控和分析项目成本和工期的强有力工具。EDM是Khamooshi和Golafshani (2014)引入仅利用时间指标来计算工期的方法，目前对于EVM和EDM与累积和(CUSUM)控制图相结合的方法还没有被研究。本文分别利用来自EVM的成本表现指标(Cost Performance Index, CPI)和来自EDM的工期表现指标(Duration Performance Index, DPI)来构造CUSUM统计量，考虑到传统的CUSUM控制图一般是监控在假定漂移大小的前提下的过程，通常取漂移量σ=|u₁-u₀|/2。在大多数实际的工艺设计中，预先确定漂移的确切大小是一件困难的事情。因而本文选用Sparks (2000)提出的自启动累积和(Adaptive CUSUM, ACUSUM)控制图和EDM与EVM来分别监控实际工程项目的工期和成本变化，以使得项目管理者及时采取纠正措施来确保项目在预算和计划工期内完成。实验结果表明ACUSUM控制图对于项目成本和工期的监控是很有潜力的。
Earned Value Management (EVM) and Earned Duration Management (EDM) are powerful tools for monitoring and analyzing project cost and duration. EDM is a method that uses only time indicators to calculate duration introduced by Khamooshi & Golafshani (2014). At present, the method of combining EVM and EDM with CUSUM control chart has not been studied. This paper uses Cost Performance Index (CPI) from EVM and Duration Performance Index (DPI) from EDM to construct CUSUM statistics, respectively. Considering that the traditional CUSUM control chart generally monitors the process on the premise of assuming the magnitude of drift, the drift is usually taken σ=|u₁-u₀|/2. In most practical process design, it is difficult to determine the exact size of drift in advance. Therefore, this paper selects the Adaptive CUSUM control chart proposed by Sparks (2000). EDM and EVM are used to monitor the duration and cost shifts of the actual project, respectively. So that the project manager can take corrective measures in time to ensure that the project is completed within the budget and planned duration. The experimental results show that ACUSUM control chart is promising for monitoring of project cost and duration.