Causal structure acquisition device, causal structure acquisition method, causal structure acquisition program and it is recorded computer-readable recording medium

摘要

PPROBLEM TO BE SOLVED: To easily acquire a causal structure of knowledge information used by an inference system for diagnostic and prediction and the like. PSOLUTION: The causal structure acquiring device 10 obtains measured data of a plurality of pairs of variables selected from a variable group including a plurality of variables from a measured data recording part 23 in a variable-to-variable relationship generation part 11 and calculates independence test statistic of the two variables based on the obtained measured data. If the test statistic is larger than an upper limit threshold value, it is determined that the two variables have causal relationship, if the test statistic is smaller than a lower limit threshold value, it is determined that the two variables do not have any causal relationship, and if the test statistic is between the two threshold values, it is determined that whether the two variables have causal relationship or not is unknown. Thus, it is possible to easily determine whether the two variables included in the variable group have causal relationship or not. PCOPYRIGHT: (C)2008,JPO&INPIT