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: "envy multi envy and revenue maximization"
  Abstract: We study the envy free pricing problem faced by a seller who wishes to maximize revenue by setting prices for bundles of items. If there is an unlimited supply of items and agents are single minded then we show that finding the revenue maximizing envy free allocation/pricing can be solved in polynomial time by reducing it to an instance of weighted independent set on a perfect graph. #R##N#We define an allocation/pricing as \textit{multi envy free} if no agent wishes to replace her allocation with the union of the allocations of some set of other agents and her price with the sum of their prices. We show that it is \textit{coNP}-hard to decide if a given allocation/pricing is multi envy free. We also show that revenue maximization multi envy free allocation/pricing is \textit{APX} hard. #R##N#Furthermore, we give efficient algorithms and hardness results for various variants of the highway problem.

Connected through hyperedge HE-1 (induced by source paper "envy regret and social welfare loss"):
  with members:
    - "the ad types problem"
    - "online learning for measuring incentive compatibility in ad auctions"
    - "note on vcg vs price raising for matching markets"
    - "communication complexity of approximate nash equilibria"
    - "the price of anarchy in auctions"
    - "setting lower bounds on truthfulness"
    - "learning in auctions regret is hard envy is easy"
    - "adam a method for stochastic optimization"

Connected through hyperedge HE-2 (induced by source paper "price doubling and item halving robust revenue guarantees for item pricing"):
  with members:
    - "a duality based unified approach to bayesian mechanism design"
    - "simple mechanisms for subadditive buyers via duality"
    - "envy free pricing in multi unit markets"
    - "mechanism design for subadditive agents via an ex ante relaxation"
    - "pricing to maximize revenue and welfare simultaneously in large markets"
    - "on the computational complexity of optimal simple mechanisms"
    - "on welfare approximation and stable pricing"
    - "secretary problems with non uniform arrival order"

Connected through hyperedge HE-3 (induced by source paper "on welfare approximation and stable pricing"):
  with members:
    - "combinatorial walrasian equilibrium"
    - "combinatorial auctions with decreasing marginal utilities"
    - "truth revelation in approximately efficient combinatorial auctions"

Connected through hyperedge HE-4 (induced by source paper "clearing markets via bundles"):
  with members:
    - "combinatorial walrasian equilibrium"
    - "lower bound for envy free and truthful makespan approximation on related machines"
    - "optimization with demand oracles"
    - "an impossibility result for truthful combinatorial auctions with submodular valuations"
    - "bundling equilibrium in combinatorial auctions"

Connected through hyperedge HE-5 (induced by source paper "combinatorial walrasian equilibrium"):
  with members:
    - "clearing markets via bundles"
    - "welfare and revenue guarantees for competitive bundling equilibrium"
    - "combinatorial auctions via posted prices"
    - "understanding incentives mechanism design becomes algorithm design"
    - "lower bound for envy free and truthful makespan approximation on related machines"
    - "optimization with demand oracles"
    - "an impossibility result for truthful combinatorial auctions with submodular valuations"
    - "bayesian incentive compatibility via fractional assignments"

Connected through hyperedge HE-6 (induced by source paper "on revenue maximization with sharp multi unit demands"):
  with members:
    - "approximating the revenue maximization problem with sharp demands"
    - "pricing ad slots with consecutive multi unit demand"
    - "on profit maximizing pricing for the highway and tollbooth problems"

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)