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: "Measuring secrecy by the probability of a successful guess"
  Abstract: A secrecy system in which both the legitimate receiver and an eavesdropper are allowed some distortion is studied. The eavesdropper is allowed to make one guess, and the considered secrecy metric is the exponent of the probability that the guess is within an acceptable distortion level. A subsequent notion of information leakage is suggested. In the absence of any shared key between the transmitter and the legitimate receiver, a single-letter characterization of the highest achievable exponent is provided. Moreover, asymptotically-optimal universal strategies for both the primary user and the eavesdropper are demonstrated, where universality means independence of the source statistics. When a secret key is shared between the transmitter and the legitimate receiver, and a rate constraint is imposed, upper and lower bounds on the optimal exponent are given. Certain sufficient conditions for the bounds to meet are provided, and examples where they apply are discussed.

Connected through hyperedge HE-1 (induced by source paper "Mechanism Design via Differential Privacy"):
  with members:
    - "i Bundle: an efficient ascending price bundle auction"
    - "Frugal path mechanisms"
    - "P4P: practical large-scale privacy-preserving distributed computation robust against malicious users"
    - "Improved approximation algorithms for maximum cut and satisfiability problems using semidefinite programming"
    - "Approximate graph coloring by semidefinite programming"
    - "An information theoretic approach for privacy metrics"
    - "Differentially Private Feature Selection via Stability Arguments, and the Robustness of the Lasso"

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: Mathematics