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: "collaborative thesaurus tagging the wikipedia way"
  Abstract: This paper explores the system of categories that is used to classify articles in Wikipedia. It is compared to collaborative tagging systems like del.icio.us and to hierarchical classification like the Dewey Decimal Classification (DDC). Specifics and commonalitiess of these systems of subject indexing are exposed. Analysis of structural and statistical properties (descriptors per record, records per descriptor, descriptor levels) shows that the category system of Wikimedia is a thesaurus that combines collaborative tagging and hierarchical subject indexing in a special way.

Connected through hyperedge HE-1 (induced by source paper "on the estimation and use of statistical modelling in information retrieval"):
  with members:
    - "part of speech based term weighting for information retrieval"
    - "social resilience in online communities the autopsy of friendster"
    - "vocabulary growth in collaborative tagging systems"
    - "the structure of broad topics on the web"
    - "search in power law networks"

Connected through hyperedge HE-2 (induced by source paper "ranking of wikipedia articles in search engines revisited fair ranking for reasonable quality"):
  with members:
    - "the retrieval effectiveness of web search engines considering results descriptions"

Connected through hyperedge HE-3 (induced by source paper "treelicious a system for semantically navigating tagged web pages"):
  with members:
    - "the structure of collaborative tagging systems"

Connected through hyperedge HE-4 (induced by source paper "tagging folksonomy co renaissance of manual indexing"):
  with members:
    - "collaborative tagging as a tripartite network"
    - "collaborative tagging and semiotic dynamics"

Connected through hyperedge HE-5 (induced by source paper "synonym search in wikipedia synarcher"):
  with members:
    - "analyzing and visualizing the semantic coverage of wikipedia and its authors"

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.IR(Information Retrieval)