Fecha de publicación: -- Fuente: Wipo "digitalization" Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for using cryptographic techniques to enhance data security and privacy and increasing computational efficiency in selecting digital components for multiple digital component slots are described. In one aspect, a method includes receiving, from a client device and by a first MPC computer of a group of MPC computers that collaborate to perform MPC computations, a composite request for digital components to display in multiple digital component slots of an electronic resource. The composite request includes first secret shares of data identifying user groups that include a user of the client device as a member. A determination is made, in collaboration with one or more second MPC computers, a first secret share of a value of each of multiple candidate parameters of a candidate expression for each digital component in a set of digital components.