human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "socially optimal design of service exchange platforms with imperfect monitoring"
  Abstract: In service exchange platforms, anonymous users exchange services with each other: clients request services and are matched to servers who provide services. Because providing good-quality services requires effort, in any single interaction a server will have no incentive to exert effort and will shirk. We show that if current servers will later become clients and want good-quality services, shirking can be eliminated by rating protocols, which maintain ratings for each user, prescribe behavior in each client-server interaction, and update ratings based on whether observed/reported behavior conforms with prescribed behavior. The rating protocols proposed are the first to achieve social optimum even when observation/reporting is imperfect (quality is incorrectly assessed/reported or reports are lost). The proposed protocols are remarkably simple, requiring only binary ratings and three possible prescribed behaviors. Key to the efficacy of the proposed protocols is that they are nonstationary, and tailor prescriptions to both current and past rating distributions.

Connected through hyperedge HE-1 (induced by source paper "rating protocol design for extortion and cooperation in the crowdsourcing contest dilemma"):
  with members:
    - "when reputation enforces evolutionary cooperation in unreliable manets"
    - "optimal prizes for all pay contests in heterogeneous crowdsourcing"
    - "iterated crowdsourcing dilemma game"
    - "reputation based incentive protocols in crowdsourcing applications"
    - "medium access control protocols with memory"

Connected through hyperedge HE-2 (induced by source paper "game theoretic design of optimal two sided rating protocols for service exchange dilemma in crowdsourcing"):
  with members:
    - "utility fair rate allocation in lte 802 11 networks"
    - "iterated crowdsourcing dilemma game"
    - "the importance of being earnest in crowdsourcing systems"

Connected through hyperedge HE-3 (induced by source paper "incentive design in peer review rating and repeated endogenous matching"):
  with members:
    - "tuned models of peer assessment in moocs"
    - "peer to peer multimedia sharing based on social norms"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.GT(Computer Science and Game Theory)