中文摘要：

专利池正成为技术专利的重要组织形式，对其开展评价是一项紧迫的工作。专利池中的专利存在着复杂的引用关系，基于专利间的引用关系，研究提出测度技术内聚性的定量指标；以典型的专利池为研究样本，运用技术内聚度分析专利池的技术内聚性变化趋势；研究表明，技术内聚度在专利池创立前呈上升趋势，在创立后逐步趋于稳定；依据专利池的技术内聚度，可以将专利池划分为松散型和紧密型。

英文摘要：

With patent pool becomes an important organization form of technical patents, the evaluation of patent pool is an urgent task. There are complicated relationships for the patent citations in patent pools. The technical cohesion index is proposed in order to quantitatively measure the technical cohesion of patent pool based on patent citations. Therefore, by utilizing the typical patent pools as research samples, the trend of technical cohesion is studied through the index. The results show that the technical cohesion is rising before patent pool formation. And the technical cohesion tends to be stable after patent pool formation. Patent pools could be divided into loose type and close type according to the values of technical cohesion index.