A bibliometric analysis on the patterns and influences of interdisciplinary research areas

本研究以专利分类为研究对象，从以下两个角度考察其“跨学科性”：(1)当观察期处于共时状态，假设各专利与被引领域之间的联系强度恒定时，被引领域数量增长的期望值；(2)根据累积被引次数随时间的增加，被引领域数量增长的经验值。从结果中可以确认，每个专利和引用领域之间的潜在联系的强度随着时间的推移而变化。特别是在“化学”领域；“冶金学”和“物理学”，以下变化是相当大的：一项专利往往在一段时间内受到有限领域的反复引用，但后来又被各个领域引用。

This study focused on the classifications assigned to patents and examined the "interdisciplinarity" from the following two perspectives: (1) expected values for growth in the number of citing fields, when regarding the observation period as being in a synchronic state and assuming that the strength of connections between each patent and citing fields is constant; and (2) empirical values for growth in the number of citing fields according to the increase in the cumulative number of citations over time. From the results, it was confirmed that the strength of potential connections between each patent and citing fields changes over time. Especially in the fields of "chemistry; metallurgy" and "physics," the following change is considerable: a patent tends to receive citations repeatedly from a limited range of fields for a while, but later comes to be cited by various fields.