Examination of Post-Processing as a Composition Technique
Post-processing refers to applying additional computations or transformations to the output of a differentially private mechanism. While basic differential privacy ensures that the original analysis outcome is protected, post-processing can potentially introduce additional privacy loss. This makes it necessary to analyse the combined effect of the initial mechanism and the post-processing step to ensure that the overall privacy guarantees remain intact.
In some cases, post-processing can improve utility without significantly compromising privacy. However, careful consideration is required to ensure that the post-processed output still adheres to privacy constraints.