Figure 3: Risk, which greatly contributes to variance and unpredictability, is reduced over time in an iterative project.
图3：风险，主要代表了变化性和不可预测性，在项目的迭代中随着时间而降低。
2
Hence, the variance diminishes over time due to collaborative interaction on new knowledge acquisition.
因此，由于在新知识的获取方面进行合作交流，方差随着时间减少了。
3
However, for the composite load has the characteristics of complex composition, random time variance and spread over different area, its exact mathematics model is still not built up.