A non-transitory computer-readable medium having computer-readable instructions stored thereon which, when executed by a computer, cause the computer to perform a method of processing data comprising the steps of: receiving data associated with event instances; and for each of a plurality of iteration methods: partitioning the incoming event instances into logical data partitions; assigning an identifier to each event instance such that events classified in the same logical data partition receive the same identifier and a given event instance is always assigned the same identifier; and inserting each event instance into a doubly-linked list associated with the identifier in an appropriate location.