项目经济评价是从国家的角度分析项目的经济合理性,它区别于项目财务评价的一个重要方面,就是试图包括所有的费用和效益,即把项目财务评价不考虑的外部费用和效益也包括进来。项目的外部效果是项目外部费用和外部效益的简称,是指项目的经济活动超出其计划范围之外对社会经济的其他部分所造成的影响。外部效果又可称为外部性效果、间 Project economic evaluation is to analyze the economic rationality of the project from a national perspective. It is different from an important aspect of project financial evaluation in that it tries to include all the costs and benefits, including the external costs and benefits not considered in the project financial evaluation . The external effect of the project is the abbreviation of external costs and external benefits of the project. It refers to the impact of the economic activities of the project beyond the scope of its plan on other parts of the social economy. External effects can be called external effects, between