Learning with User-Level Local Differential Privacy

Understand

User-level privacy is important in distributed systems.

• Previous research primarily focuses on the central model, while the local models have received much less attention.
• Under the central model, user-level DP is strictly stronger than the item-level one.
• However, under the local model, the relationship between user-level and item-level LDP becomes more complex, thus the analysis is crucially different.