ABNORMAL MODULATION CAUSE IDENTIFICATION DEVICE, ABNORMAL MODULATION CAUSE IDENTIFICATION METHOD, AND ABNORMAL MODULATION CAUSE IDENTIFICATION PROGRAM

Performance to identify a cause of abnormal irregularity in a production facility is improved. An abnormal irregularity cause identifying device includes a process data acquisition unit that reads, from a storage device storing pieces of process data continuously output by a plurality of sensors included in a production facility, the pieces of process data, an abnormality determination unit that calculates an abnormality degree representing an extent of an irregularity of process data of the pieces of process data read by the process data acquisition unit, and a cause diagnosis unit that determines, for each of the pieces of process data output by the corresponding one of the plurality of sensors, whether the abnormality degree calculated by the abnormality determination unit satisfies a predetermined criterion by using causal relation information defining a combination of a causal relation between a cause and the irregularity, which appears as an influence resulting from the cause, of the process data output by each of the plurality of sensors in a hierarchical manner along time series.