Computer-implemented method for providing an encrypted dataset providing a global trained function, computer-implemented method for recovering personal information, computer system and computer program

Abstract

Respective local parameters parametrizing a base function are determined to provide at least one local trained function for each of multiple client systems by training the respective local trained function using machine learning with multiple training datasets on the respective client system, wherein at least some of the training datasets are specific to the respective client system. A respective local plaintext dataset including the local parameters of the respective local trained function is encrypted to generate a respective local encrypted dataset on the respective client system. The local encrypted datasets are transmitted to an aggregating system, and the global encrypted dataset is calculated from the local encrypted datasets using the calculation algorithm.