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: "improved efficiency guarantees in auctions with budgets"
  Abstract: We study the efficiency guarantees in the simple auction environment where the auctioneer has one unit of divisible good to be distributed among a number of budget constrained agents. With budget constraints, the social welfare cannot be approximated by a better factor than the number of agents by any truthful mechanism. Thus, we follow a recent work by Dobzinski and Leme (ICALP 2014) to approximate the liquid welfare, which is the welfare of the agents each capped by her/his own budget. We design a new truthful auction with an approximation ratio of $\frac{\sqrt{5}+1}{2} \approx 1.618$, improving the best previous ratio of $2$ when the budgets for agents are public knowledge and their valuation is linear (additive). In private budget setting, we propose the first constant approximation auction with approximation ratio of $34$. Moreover, this auction works for any valuation function. Previously, only $O(\log n)$ approximation was known for linear and decreasing marginal (concave) valuations, and $O(\log^2 n)$ approximation was known for sub-additive valuations.

Connected through hyperedge HE-1 (induced by source paper "a note on the efficiency of position mechanisms with budget constraints"):
  with members:
    - "the efficiency of resource allocation mechanisms for budget constrained users"
    - "the price of anarchy in auctions"
    - "on the efficiency of the proportional allocation mechanism for divisible resources"
    - "liquid price of anarchy"
    - "welfare guarantees for proportional allocations"
    - "efficiency guarantees in auctions with budgets"
    - "on the stability of generalized second price auctions with budgets"
    - "expressiveness and robustness of first price position auctions"

Connected through hyperedge HE-2 (induced by source paper "the efficiency of resource allocation mechanisms for budget constrained users"):
  with members:
    - "the price of anarchy in auctions"
    - "on the efficiency of the proportional allocation mechanism for divisible resources"
    - "liquid price of anarchy"
    - "welfare guarantees for proportional allocations"
    - "efficiency guarantees in auctions with budgets"
    - "composable and efficient mechanisms"

Connected through hyperedge HE-3 (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"
    - "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"
    - "efficiency guarantees in auctions with budgets"

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)