Apparatus, method, and program product for calculating abnormality based on degree of correlation destruction

In the invariant analysis, a fault cause is judged correctly. A correlation model storing unit (112) of an operation management apparatus (100) stores a correlation model including one or more correlation functions each of which indicates a correlation between two metrics different each other among a plurality of metrics in a system. The correlation destruction detecting unit (103) detects correlation destruction of the correlation which is included in the correlation model by applying newly inputted values of the plurality of metrics to the correlation model. The abnormality calculation unit (104) calculates and outputs a centrality degree which indicates a degree to which a first metric is estimated to be center of distribution of correlation destruction on the basis of a correlation destruction degree of one or more correlations between each of one or more second metrics having a correlation with the first metric and each of one or more metrics other than the first metric among the plurality of metrics.