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: "comments on approximate characterizations for the gaussian source broadcast distortion region"
  Abstract: Recently, Tian  et al.   [1]  considered joint source-channel coding of transmitting a Gaussian source over    $K$   -user Gaussian broadcast channel, and derived an outer bound on the admissible distortion region. In  [1] , they stated “due to its nonlinear form, it appears difficult to determine whether it is always looser than the trivial outer bound in all distortion regimes with bandwidth compression”. However, in this correspondence we solve this problem and prove that for the bandwidth expansion case (with    $K\geq 2$   ), this outer bound is strictly tighter than the trivial outer bound with each user being optimal in the point-to-point setting; while for the bandwidth compression or bandwidth match case, this outer bound actually degenerates to the trivial outer bound. Therefore, our results imply that on one hand, the outer bound given in  [1]  is nontrivial only for Gaussian broadcast communication (   $K\geq 2$   ) with bandwidth expansion; on the other hand, unfortunately, no nontrivial outer bound exists so far for Gaussian broadcast communication (   $K\geq 2$   ) with bandwidth compression.

Connected through hyperedge HE-1 (induced by source paper "distortion bounds for source broadcast over degraded channel"):
  with members:
    - "a source channel separation theorem with application to the source broadcast problem"
    - "outer bounds on the admissible source region for broadcast channels with correlated sources"
    - "hybrid coding an interface for joint source channel coding and network communication"
    - "achievability proof via output statistics of random binning"
    - "hybrid digital analog codes for source channel broadcast of gaussian sources over gaussian channels"
    - "the achievable distortion region of bivariate gaussian source on gaussian broadcast channel"
    - "on the capacity of the discrete memoryless broadcast channel with feedback"
    - "wyner ziv coding over broadcast channels digital schemes"

Connected through hyperedge HE-2 (induced by source paper "distortion bounds for source broadcast problem"):
  with members:
    - "a source channel separation theorem with application to the source broadcast problem"
    - "distortion bounds for source broadcast over degraded channel"
    - "outer bounds on the admissible source region for broadcast channels with correlated sources"
    - "achievability proof via output statistics of random binning"
    - "hybrid digital analog codes for source channel broadcast of gaussian sources over gaussian channels"
    - "on the capacity of the discrete memoryless broadcast channel with feedback"
    - "wyner ziv coding over broadcast channels digital schemes"

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)