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: "budgetary effects on pricing equilibrium in online markets"
  Abstract: Following the work of Babaioff et al, we consider the pricing game with strategic vendors and a single buyer, modeling a scenario in which multiple competing vendors have very good knowledge of a buyer, as is common in online markets. We add to this model the realistic assumption that the buyer has a fixed budget and does not have unlimited funds. When the buyer's valuation function is additive, we are able to completely characterize the different possible pure Nash Equilibria (PNE) and in particular obtain a necessary and sufficient condition for uniqueness. Furthermore, we characterize the market clearing (or Walresian) equilibria for all submodular valuations. #R##N#Surprisingly, for certain monotone submodular function valuations, we show that the pure NE can exhibit some counterintuitive phenomena; namely, there is a valuation such that the pricing will be market clearing and within budget if the buyer does not reveal the budget but will result in a smaller set of allocated items (and higher prices for items) if the buyer does reveal the budget. It is also the case that the conditions that guarantee market clearing in Babaioff et al for submodular functions are not necessarily market clearing when there is a budget. Furthermore, with respect to social welfare, while without budgets all equilibria are optimal (i.e. POA = POS = 1), we show that with budgets the worst equilibrium may only achieve 1/(n-2) of the best equilibrium.

Connected through hyperedge HE-1 (induced by source paper "electronic markets with multiple submodular buyers"):
  with members:
    - "price competition in online combinatorial markets"
    - "the pricing war continues on competitive multi item pricing"

Connected through hyperedge HE-2 (induced by source paper "seasonal goods and spoiled milk pricing for a limited shelf life"):
  with members:
    - "pricing policies for selling indivisible storable goods to strategic consumers"
    - "price competition in online combinatorial markets"
    - "the pricing war continues on competitive multi item pricing"

Connected through hyperedge HE-3 (induced by source paper "envy free pricing in multi unit markets"):
  with members:
    - "posted pricing sans discrimination"
    - "the invisible hand of dynamic market pricing"
    - "combinatorial auctions via posted prices"
    - "the complexity of fairness through equilibrium"
    - "reducing revenue to welfare maximization approximation algorithms and other generalizations"
    - "optimal multi dimensional mechanism design reducing revenue to welfare maximization"
    - "multi unit auctions beyond roberts"
    - "mechanisms for multi unit auctions"

Connected through hyperedge HE-4 (induced by source paper "efficiency and complexity of price competition among single product vendors"):
  with members:
    - "price competition in online combinatorial markets"
    - "price competition in networked markets how do monopolies impact social welfare"
    - "the pricing war continues on competitive multi item pricing"
    - "enforcing efficient equilibria in network design games via subsidies"
    - "the cost of stability in coalitional games"
    - "a new multilayered pcp and the hardness of hypergraph vertex cover"

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)