著者
前野 義晴 大澤 幸生
出版者
一般社団法人 人工知能学会
雑誌
人工知能学会論文誌 (ISSN:13460714)
巻号頁・発行日
vol.24, no.5, pp.376-385, 2009 (Released:2009-06-11)
参考文献数
34
被引用文献数
1

Can we discover a node which is not observable directly but mediates the stochastic diffusion process in a network? We address such a node discovery and mathematically formulate the basic concept which is promising to solving the problem in general. The proposed method is tested with a node discovery in a Barabási-Albert model which the conventional method raised and partially succeeded in. Its performance is measured with the receiver operating characteristic curves and van Rijsbergen's F-measure (the harmonic mean of precision and recall). The proposed method succeeds in discovering an unobservable peripheral node, and an unobservable hub node in a less clustered network where the conventional method failed.
著者
大澤 幸生 谷内田 正彦
出版者
社団法人人工知能学会
雑誌
人工知能学会誌 (ISSN:09128085)
巻号頁・発行日
vol.15, no.4, pp.665-672, 2000-07-01
被引用文献数
6

KeyGraph, an automatic document indexing method for extracting keywords expressing the assertions of a document, i. e. assertions supported by the outlines based on the basic concepts of the document, is applied to detecting risky active faults from earthquake history data. Here a history data is regarded as a document to be indexed, and active faults stressed strongly i. e. with near-future earthquake risks are obtained as keywords asserted in the document. This paper presents this method and its seismologic semantics. The semantics shows that KeyGraph is a model of earthquake occurrences, which considers less details of local land crust activities than in seismology, but more of global interactions among active faults. Experimentally, faults with near-future earthquake risks were obtained with high accuracies, and the shifts of risky areas after big earthquakes datected by KeyGraph corresponded with realistic tectonics.