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: "simultaneous auctions are almost efficient"
  Abstract: Simultaneous item auctions are simple procedures for allocating items to bidders with potentially complex preferences over different item sets. In a simultaneous auction, every bidder submits bids on all items simultaneously. The allocation and prices are then resolved for each item separately, based solely on the bids submitted on that item. Such procedures occur in practice (e.g. eBay) but are not truthful. We study the efficiency of Bayesian Nash equilibrium (BNE) outcomes of simultaneous first- and second-price auctions when bidders have complement-free (a.k.a. subadditive) valuations. We show that the expected social welfare of any BNE is at least 1/2 of the optimal social welfare in the case of first-price auctions, and at least 1/4 in the case of second-price auctions. These results improve upon the previously-known logarithmic bounds, which were established by [Hassidim, Kaplan, Mansour and Nisan '11] for first-price auctions and by [Bhawalkar and Roughgarden '11] for second-price auctions.

Connected through hyperedge HE-1 (induced by source paper "complexity theory game theory and economics the barbados lectures"):
  with members:
    - "a round collapse theorem for computationally sound protocols or tfnp is hard on average in pessiland"
    - "on communication complexity of fixed point computation"
    - "near optimal communication lower bounds for approximate nash equilibria"
    - "query to communication lifting for bpp"
    - "lifting randomized query complexity to randomized communication complexity"
    - "settling the complexity of computing approximate two player nash equilibria"
    - "communication complexity of approximate nash equilibria"
    - "the price of anarchy in auctions"

Connected through hyperedge HE-2 (induced by source paper "pricing multi unit markets"):
  with members:
    - "a simple and approximately optimal mechanism for a buyer with complements"
    - "the invisible hand of dynamic market pricing"
    - "pricing online decisions beyond auctions"
    - "a simple and approximately optimal mechanism for an additive buyer"
    - "revenue maximization for selling multiple correlated items"
    - "combinatorial auctions via posted prices"
    - "dynamic pricing with limited supply"
    - "non price equilibria in markets of discrete goods"

Connected through hyperedge HE-3 (induced by source paper "combinatorial auctions do need modest interaction"):
  with members:
    - "on estimating maximum matching size in graph streams"
    - "on simultaneous two player combinatorial auctions"
    - "best response dynamics in combinatorial auctions with item bidding"
    - "computational efficiency requires simple taxation"
    - "welfare maximization with limited interaction"
    - "combinatorial auctions via posted prices"
    - "economic efficiency requires interaction"
    - "learning valuation functions"

Connected through hyperedge HE-4 (induced by source paper "the price of anarchy in auctions"):
  with members:
    - "a duality based unified approach to bayesian mechanism design"
    - "best response dynamics in combinatorial auctions with item bidding"
    - "simple mechanisms for agents with complements"
    - "the price of anarchy in large games"
    - "on the economic efficiency of the combinatorial clock auction"
    - "on the efficiency of all pay mechanisms"
    - "learning and efficiency in games with dynamic population"
    - "no regret learning in bayesian games"

Connected through hyperedge HE-5 (induced by source paper "simple mechanisms for agents with complements"):
  with members:
    - "simple auctions for agents with complements"
    - "interpolating between truthful and non truthful mechanisms for combinatorial auctions"
    - "the pseudo dimension of near optimal auctions"
    - "greedy algorithms make efficient mechanisms"
    - "simple mechanisms for a subadditive buyer and applications to revenue monotonicity"
    - "on the complexity of computing an equilibrium in combinatorial auctions"
    - "a simple and approximately optimal mechanism for an additive buyer"
    - "an n to 1 bidder reduction for multi item auctions and its applications"

Connected through hyperedge HE-6 (induced by source paper "an empirical study on computing equilibria in polymatrix games"):
  with members:
    - "approximating nash equilibria in tree polymatrix games"
    - "from duels to battefields computing equilibria of blotto and other games"
    - "an empirical study of finding approximate equilibria in bimatrix games"
    - "coordination games on graphs"
    - "on the complexity of computing an equilibrium in combinatorial auctions"
    - "inapproximability of nash equilibrium"
    - "computing approximate nash equilibria in polymatrix games"
    - "computing nash equilibria of action graph games"

Connected through hyperedge HE-7 (induced by source paper "correlated and coarse equilibria of single item auctions"):
  with members:
    - "learning in auctions regret is hard envy is easy"
    - "on the complexity of computing an equilibrium in combinatorial auctions"
    - "tight bounds for the price of anarchy of simultaneous first price auctions"
    - "composable and efficient mechanisms"
    - "non price equilibria in markets of discrete goods"

Connected through hyperedge HE-8 (induced by source paper "liquid price of anarchy"):
  with members:
    - "on the efficiency of the proportional allocation mechanism for divisible resources"
    - "mechanism design for crowdsourcing an optimal 1 1 e competitive budget feasible mechanism for large markets"
    - "improved efficiency guarantees in auctions with budgets"
    - "on the complexity of computing an equilibrium in combinatorial auctions"
    - "truthful multi unit procurements with budgets"
    - "price of anarchy for auction revenue"
    - "welfare guarantees for proportional allocations"
    - "combinatorial walrasian equilibrium"

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)