human: Given a node-centered hypergraph: <hypergraph>, where nodes represent authors and hyperedges represent groups of authors who co-authored the same paper.

Details of the hypergraph:
Center node: "On Linear Refinement of Differential Privacy-Preserving Query Answering"
  Abstract: Recent work showed the necessity of incorporating a user’s background knowledge to improve the accuracy of estimates from noisy responses of histogram queries. Various types of constraints (e.g., linear constraints, ordering constraints, and range constraints) may hold on the true (non-randomized) answers of histogram queries. So the idea was to apply the constraints over the noisy responses and find a new set of answers (called refinements) that are closest to the noisy responses and also satisfy known constraints. As a result, the refinements expect to boost the accuracy of final histogram query results. However, there is one key question: is the ratio of the distributions of the results after refinements from any two neighbor databases still bounded? In this paper, we introduce a new definition, ρ-differential privacy on refinement, to quantify the change of distributions of refinements. We focus on one representative refinement, the linear refinement with linear constraints and study the relationship between the classic e-differential privacy ( on responses) and our ρ-differential privacy on refinement. We demonstrate the conditions when the ρ-differential privacy on refinement achieves the same e-differential privacy. We argue privacy breaches could incur when the conditions do not meet.

Connected through hyperedge HE-1 (induced by source paper "More Efficient Constant-Round Multi-party Computation from BMR and SHE"):
  with members:
    - "Authenticating Computation on Groups: New Homomorphic Primitives and Applications"
    - "A Secure Obfuscator for Encrypted Blind Signature Functionality"
    - "On Obfuscation with Random Oracles"
    - "Graph-Induced Multilinear Maps from Lattices"
    - "Blazing Fast 2PC in the Offline/Online Setting with Security for Malicious Adversaries"
    - "Non-Interactive Secure Computation Based on Cut-and-Choose"
    - "Efficient Secure and Verifiable Outsourcing of Matrix Multiplications"
    - "Rational Secure Two-party Computation in Social Cloud"

Question: Please tell me which research area the center author belongs to. The 4 classes are: Computer science, Mathematics, Engineering, Economics, Psychology, Business. Directly output the class name.

gpt: Computer science