Data analysis server, data analysis system, and data analysis method

摘要

A data analysis server holds base-point-added information, wherein the base-point-added information includes a value of an explanatory variable encrypted by first high-performance encryption, a value of a response variable encrypted by a predetermined encryption scheme, and a base point based on frequencies of the value of the explanatory variable in information for learning are associated with one another, wherein the data analysis server: executes decision tree generation processing for generating a decision tree having a leaf node associated with the value of the response variable encrypted by the predetermined encryption scheme, which is included in the base-point-added information; and execute branching rule determine processing in decision tree generation processing without decrypting the value of the explanatory variable and the base point corresponding.