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: "on some winning strategies for the iterated prisoner s dilemma or mr nice guy and the cosa nostra"
  Abstract: We submitted two kinds of strategies to the iterated prisoner's dilemma (IPD) competitions organized by Graham Kendall, Paul Darwen and Xin Yao in 2004 and 2005. Our strategies performed exceedingly well in both years. One type is an intelligent and optimistic enhanced version of the well known TitForTat strategy which we named OmegaTitForTat. It recognizes common behaviour patterns and detects and recovers from repairable mutual defect deadlock situations, otherwise behaving much like TitForTat. The second type consists of a set of strategies working together as a team. These group strategies have one distinguished individual Godfather strategy that plays OmegaTitForTat against non-members while heavily profiting from the behaviour of the other members of his group, the Hitman. The Hitman willingly let themselves being abused by their Godfather while themselves lowering the scores of all other players as much as possible, thus further maximizing the performance of their Godfather in relation to other participants. The study of collusion in the simplified framework of the iterated prisoner's dilemma allows us to draw parallels to many common aspects of reality both in Nature as well as Human Society, and therefore further extends the scope of the iterated prisoner's dilemma as a metaphor for the study of cooperative behaviour in a new and natural direction. We further provide evidence that it will be unavoidable that such group strategies will dominate all future iterated prisoner's dilemma competitions as they can be stealthy camouflaged as non-group strategies with arbitrary subtlety. Moreover, we show that the general problem of recognizing stealth colluding strategies is undecidable in the theoretical sense.

Connected through hyperedge HE-1 (induced by source paper "recognising and evaluating the effectiveness of extortion in the iterated prisoner s dilemma"):
  with members:
    - "evolutionary extortion and mischief zero determinant strategies in iterated 2x2 games"

Connected through hyperedge HE-2 (induced by source paper "reinforcement learning produces dominant strategies for the iterated prisoner s dilemma"):
  with members:
    - "an open framework for the reproducible study of the iterated prisoner s dilemma"
    - "the numpy array a structure for efficient numerical computation"
    - "evolutionary algorithms for reinforcement learning"

Connected through hyperedge HE-3 (induced by source paper "an open framework for the reproducible study of the iterated prisoner s dilemma"):
  with members:
    - "top tips to make your research irreproducible"
    - "share and enjoy publishing useful and usable scientific models"
    - "building a framework for predictive science"

Connected through hyperedge HE-4 (induced by source paper "monte carlo bayesian reinforcement learning"):
  with members:
    - "model based bayesian exploration"
    - "pegasus a policy search method for large mdps and pomdps"
    - "point based pomdp algorithms improved analysis and implementation"
    - "model based bayesian reinforcement learning in large structured domains"
    - "a bayesian sampling approach to exploration in reinforcement learning"

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)