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: "online market intermediation"
  Abstract: We study a dynamic market setting where an intermediary interacts with an unknown large sequence of agents that can be either sellers or buyers: their identities, as well as the sequence length $n$, are decided in an adversarial, online way. Each agent is interested in trading a single item, and all items in the market are identical. The intermediary has some prior, incomplete knowledge of the agents' values for the items: all seller values are independently drawn from the same distribution $F_S$, and all buyer values from $F_B$. The two distributions may differ, and we make standard regularity assumptions, namely that $F_B$ is MHR and $F_S$ is log-concave. #R##N#We study online, posted-price mechanisms, and analyse two objectives: that of maximizing the intermediary's profit and that of maximizing the social welfare, under a competitive analysis benchmark. First, on the negative side, for general agent sequences we prove tight competitive ratios of $\varTheta(\sqrt{n})$ and $\varTheta(\ln n)$, respectively for the two objectives. On the other hand, under the extra assumption that the intermediary knows some bound $\alpha$ on the ratio between the number of sellers and buyers, we design asymptotically optimal online mechanisms with competitive ratios of $1+o(1)$ and $4$, respectively. Additionally, we study the model were the number of items that can be stored in stock throughout the execution is bounded, in which case the competitive ratio for the profit is improved to $O(\ln n)$.

Connected through hyperedge HE-1 (induced by source paper "efficient two sided markets with limited information"):
  with members:
    - "optimal single choice prophet inequalities from samples"
    - "bulow klemperer style results for welfare maximization in two sided markets"
    - "improved truthful mechanisms for combinatorial auctions with submodular bidders"
    - "online trading as a secretary problem"
    - "the best of both worlds asymptotically efficient mechanisms with a guarantee on the expected gains from trade"
    - "approximating gains from trade in two sided markets via simple mechanisms"
    - "fixed price approximability of the optimal gain from trade"
    - "sbba a strongly budget balanced double auction mechanism"

Connected through hyperedge HE-2 (induced by source paper "optimal pricing for mhr and lambda regular distributions"):
  with members:
    - "optimal auctions vs anonymous pricing beyond linear utility"
    - "optimal pricing for mhr distributions"
    - "tight revenue gaps among simple mechanisms"
    - "tight approximation ratio of anonymous pricing"
    - "prophet secretary for combinatorial auctions and matroids"
    - "revenue gaps for discriminatory and anonymous sequential posted pricing"
    - "revenue gaps for static and dynamic posted pricing of homogeneous goods"
    - "the sample complexity of revenue maximization"

Connected through hyperedge HE-3 (induced by source paper "optimal pricing for mhr distributions"):
  with members:
    - "tight revenue gaps among simple mechanisms"
    - "revenue gaps for discriminatory and anonymous sequential posted pricing"
    - "randomization beats second price as a prior independent auction"
    - "the vcg mechanism for bayesian scheduling"
    - "optimal auctions vs anonymous pricing"
    - "bayesian combinatorial auctions expanding single buyer mechanisms to many buyers"
    - "extreme value theorems for optimal multidimensional pricing"
    - "mechanism design via correlation gap"

Connected through hyperedge HE-4 (induced by source paper "multi unit bilateral trade"):
  with members:
    - "online trading as a secretary problem"
    - "approximating gains from trade in two sided markets via simple mechanisms"
    - "fixed price approximability of the optimal gain from trade"
    - "muda a truthful multi unit double auction mechanism"
    - "almost efficient mechanisms for bilateral trading"
    - "online truthful mechanisms for multi sided markets"
    - "simple and near optimal mechanisms for market intermediation"

Connected through hyperedge HE-5 (induced by source paper "online trading as a secretary problem"):
  with members:
    - "approximating gains from trade in two sided markets via simple mechanisms"
    - "fixed price approximability of the optimal gain from trade"
    - "sbba a strongly budget balanced double auction mechanism"
    - "combinatorial auctions via posted prices"
    - "algorithms for secretary problems on graphs and hypergraphs"

Connected through hyperedge HE-6 (induced by source paper "fixed price approximability of the optimal gain from trade"):
  with members:
    - "approximating gains from trade in two sided markets via simple mechanisms"
    - "markets with strategic multi minded mediators"
    - "sbba a strongly budget balanced double auction mechanism"
    - "approximately efficient two sided combinatorial auctions"
    - "online truthful mechanisms for multi sided markets"

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)