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: "combinatorial auctions without money"
  Abstract: Algorithmic Mechanism Design attempts to marry computation and incentives, mainly by leveraging monetary transfers between designer and selfish agents involved. This is principally because in absence of money, very little can be done to enforce truthfulness. However, in certain applications, money is unavailable, morally unacceptable or might simply be at odds with the objective of the mechanism. For example, in Combinatorial Auctions (CAs), the paradigmatic problem of the area, we aim at solutions of maximum social welfare but still charge the society to ensure truthfulness. Additionally, truthfulness of CAs is poorly understood already in the case in which bidders happen to be interested in only two different sets of goods. #R##N#We focus on the design of incentive-compatible CAs without money in the general setting of $k$-minded bidders. We trade monetary transfers with the observation that the mechanism can detect certain lies of the bidders: i.e., we study truthful CAs with verification and without money. We prove a characterization of truthful mechanisms, which makes an interesting parallel with the well-understood case of CAs with money for single-minded bidders. We then give a host of upper bounds on the approximation ratio obtained by either deterministic or randomized truthful mechanisms when the sets and valuations are private knowledge of the bidders. (Most of these mechanisms run in polynomial time and return solutions with (nearly) best possible approximation guarantees.) We complement these positive results with a number of lower bounds (some of which are essentially tight) that hold in the easier case of public sets. We thus provide an almost complete picture of truthfully approximating CAs in this general setting with multi-dimensional bidders.

Connected through hyperedge HE-1 (induced by source paper "improved truthful mechanisms for combinatorial auctions with submodular bidders"):
  with members:
    - "complement free couples must communicate a hardness result for two player combinatorial auctions"
    - "beyond 1 2 approximation for submodular maximization on massive data streams"
    - "prophet secretary for combinatorial auctions and matroids"
    - "on simultaneous two player combinatorial auctions"
    - "combinatorial auctions do need modest interaction"
    - "breaking the logarithmic barrier for truthful combinatorial auctions with submodular bidders"
    - "computational efficiency requires simple taxation"
    - "online matroid intersection beating half for random arrival"

Connected through hyperedge HE-2 (induced by source paper "probabilistic verification for obviously strategyproof mechanisms"):
  with members:
    - "gibbard satterthwaite success stories and obvious strategyproofness"
    - "sequential posted price mechanisms with correlated valuations"
    - "no stable matching mechanism is obviously strategy proof"
    - "a simple and approximately optimal mechanism for an additive buyer"
    - "a truthful randomized mechanism for combinatorial public projects via convex optimization"

Connected through hyperedge HE-3 (induced by source paper "partial verification as a substitute for money"):
  with members:
    - "truthful assignment without money"

Connected through hyperedge HE-4 (induced by source paper "who to trust for truthfully maximizing welfare"):
  with members:
    - "truthful approximations to range voting"
    - "the exponential mechanism for social welfare private truthful and nearly optimal"
    - "on the power of deterministic mechanisms for facility location games"
    - "an impossibility result for truthful combinatorial auctions with submodular valuations"
    - "approximately optimal mechanism design via differential privacy"
    - "on the power of randomization in algorithmic mechanism design"
    - "optimal mechansim design and money burning"

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)