Amazon calculates a product’s star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers, and factors that establish reviewer trustworthiness.
Three stories repeated - Editing error? - with none of the characters noticing. I understand the translator trying to keep to some of old English terminology, but updating to make it easier reading and understanding would have helped.