An information processing device has a data generator that generates pseudo data of normal data and pseudo data of abnormal data, on the basis of the normal data, similar data of the normal data, the abnormal data, and similar data of the abnormal data, first update circuitry that updates a first parameter multiplied by the pseudo data of the normal data to obtain an abnormality degree of the pseudo data of the normal data and multiplied by the pseudo data of the abnormal data to obtain an abnormality degree of the pseudo data of the abnormal data, and second update circuitry that updates a second parameter multiplied by the normal data to obtain the similar data of the normal data and a third parameter multiplied by the abnormal data to obtain the similar data of the abnormal data.