Covert Learning: How to Learn with an Untrusted Intermediary

Ran Canetti, Ari Karchmer

Abstract: We consider the task of learning a function via oracle queries, where the queries and responses are monitored (and perhaps also modified) by an untrusted intermediary. Our goal is twofold: First, we would like to prevent the intermediary from gaining any information about either the function or the learner’s intentions (e.g. the particular hypothesis class the learner is considering). Second, we would like to curb the intermediary’s ability to meaningfully interfere with the learning process, even when it can modify the oracles’ responses.