* Shorter version accepted in ICML Workshop on Federated Learning, July
2020, and CCS Workshop on Privacy-Preserving Machine Learning in Practice,
November 2020 Access Paper or Ask Questions
* This work is published in IEEE Transactions on Information Theory and
presented in part at the NIPS 2015 Workshop on Machine Learning Systems and
the IEEE ISIT 2016 Access Paper or Ask Questions
* improved log factor in main result; added discussion on comparison
probabilities close to zero; added numerical results Access Paper or Ask Questions