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: "choosing products in social networks"
  Abstract: We study the consequences of adopting products by agents who form a social network. To this end we use the threshold model introduced in Apt and Markakis, arXiv:1105.2434, in which the nodes influenced by their neighbours can adopt one out of several alternatives, and associate with such each social network a strategic game between the agents. The possibility of not choosing any product results in two special types of (pure) Nash equilibria. #R##N#We show that such games may have no Nash equilibrium and that determining the existence of a Nash equilibrium, also of a special type, is NP-complete. The situation changes when the underlying graph of the social network is a DAG, a simple cycle, or has no source nodes. For these three classes we determine the complexity of establishing whether a (special type of) Nash equilibrium exists. #R##N#We also clarify for these categories of games the status and the complexity of the finite improvement property (FIP). Further, we introduce a new property of the uniform FIP which is satisfied when the underlying graph is a simple cycle, but determining it is co-NP-hard in the general case and also when the underlying graph has no source nodes. The latter complexity results also hold for verifying the property of being a weakly acyclic game.

Connected through hyperedge HE-1 (induced by source paper "paradoxes in social networks with multiple products"):
  with members:
    - "graphical models for game theory"
    - "social network games with obligatory product selection"
    - "social networks with competing products"
    - "on the hardness of network design for bottleneck routing games"
    - "social network games"
    - "diffusion in social networks with competing products"
    - "competitive contagion in networks"

Connected through hyperedge HE-2 (induced by source paper "social network games with obligatory product selection"):
  with members:
    - "graphical models for game theory"
    - "paradoxes in social networks with multiple products"
    - "on the hardness of network design for bottleneck routing games"
    - "social network games"
    - "diffusion in social networks with competing products"

Connected through hyperedge HE-3 (induced by source paper "social network games"):
  with members:
    - "graphical models for game theory"
    - "social network games with obligatory product selection"
    - "paradoxes in social networks with multiple products"
    - "a classification of weakly acyclic games"
    - "social networks with competing products"
    - "diffusion in social networks with competing products"

Connected through hyperedge HE-4 (induced by source paper "social networks with competing products"):
  with members:
    - "paradoxes in social networks with multiple products"
    - "social network games"
    - "diffusion in social networks with competing products"
    - "competitive contagion in networks"
    - "adaptive submodularity theory and applications in active learning and stochastic optimization"

Connected through hyperedge HE-5 (induced by source paper "the grammar hammer of 2012"):
  with members:
    - "guided grammar convergence"
    - "guided grammar convergence full case study report generated by converge guided"
    - "mediawiki grammar recovery"
    - "well typed islands parse faster"

Connected through hyperedge HE-6 (induced by source paper "a classification of weakly acyclic games"):
  with members:
    - "on dynamics in selfish network creation"
    - "on the structure of weakly acyclic games"
    - "order independence and rationalizability"

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.SI(Social and Information Networks)