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: "an improvement of cover el gamal s compress and forward relay scheme"
  Abstract: The compress-and-forward relay scheme developed by (Cover and El Gamal, 1979) is improved with a modification on the decoding process. The improvement follows as a result of realizing that it is not necessary for the destination to decode the compressed observation of the relay; and even if the compressed observation is to be decoded, it can be more easily done by joint decoding with the original message, rather than in a successive way. An extension to multiple relays is also discussed.

Connected through hyperedge HE-1 (induced by source paper "a unified relay framework with both d f and c f relay nodes"):
  with members:
    - "compress and forward scheme for relay networks backword decoding and connection to bisubmodular flows"
    - "selective coding strategy for unicast composite networks"
    - "wireless network information flow a deterministic approach"
    - "short message quantize forward network coding"
    - "on the optimal compressions in the compress and forward relay schemes"
    - "noisy network coding"
    - "lecture notes on network information theory"
    - "analysis of a mixed strategy for multiple relay networks"

Connected through hyperedge HE-2 (induced by source paper "on the optimal compressions in the compress and forward relay schemes"):
  with members:
    - "lecture notes on network information theory"

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.IT(Information Theory)