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: "negative emotions boost user activity at bbc forum"
  Abstract: We present an empirical study of user activity in online BBC discussion forums, measured by the number of posts written by individual debaters and the average sentiment of these posts. Nearly 2.5 million posts from over 18 thousand users were investigated. Scale-free distributions were observed for activity in individual discussion threads as well as for overall activity. The number of unique users in a thread normalized by the thread length decays with thread length, suggesting that thread life is sustained by mutual discussions rather than by independent comments. Automatic sentiment analysis shows that most posts contain negative emotions and the most active users in individual threads express predominantly negative sentiments. It follows that the average emotion of longer threads is more negative and that threads can be sustained by negative comments. An agent-based computer simulation model has been used to reproduce several essential characteristics of the analyzed system. The model stresses the role of discussions between users, especially emotionally laden quarrels between supporters of opposite opinions, and represents many observed statistics of the forum.

Connected through hyperedge HE-1 (induced by source paper "an agent based model for emotion contagion and competition in online social media"):
  with members:
    - "limited individual attention and online virality of low quality information"
    - "measuring emotional contagion in social media"
    - "anger is more influential than joy sentiment correlation in weibo"
    - "agent based model for rural urban migration a dynamic consideration"
    - "the role of social networks in information diffusion"
    - "twitter reciprocal reply networks exhibit assortativity with respect to happiness"
    - "happiness is assortative in online social networks"
    - "weak ties subtle role of information diffusion in online social networks"

Connected through hyperedge HE-2 (induced by source paper "anger is more influential than joy sentiment correlation in weibo"):
  with members:
    - "twitter reciprocal reply networks exhibit assortativity with respect to happiness"
    - "happiness is assortative in online social networks"
    - "twitter mood predicts the stock market"
    - "measuring the happiness of large scale written expression songs blogs and presidents"
    - "thumbs up sentiment classification using machine learning techniques"

Connected through hyperedge HE-3 (induced by source paper "the dynamics of emotional chats with bots experiment and agent based simulations"):
  with members:
    - "the anatomy of the facebook social graph"
    - "bloggers behavior and emergent communities in blog space"

Connected through hyperedge HE-4 (induced by source paper "the role of emotional variables in the classification and prediction of collective social dynamics"):
  with members:
    - "twitter mood predicts the stock market"
    - "collective dynamics of social annotation"

Connected through hyperedge HE-5 (induced by source paper "discovering basic emotion sets via semantic clustering on a twitter corpus"):
  with members:
    - "twitter mood predicts the stock market"
    - "between conjecture and memento shaping a collective emotional perception of the future"
    - "thumbs up or thumbs down semantic orientation applied to unsupervised classification of reviews"
    - "mining the web for synonyms pmi ir versus lsa on toefl"

Connected through hyperedge HE-6 (induced by source paper "happiness is assortative in online social networks"):
  with members:
    - "twitter mood predicts the stock market"
    - "measuring the happiness of large scale written expression songs blogs and presidents"
    - "v like formations in flocks of artificial birds"
    - "social networks that matter twitter under the microscope"

Connected through hyperedge HE-7 (induced by source paper "patterns of emotional blogging and emergence of communities agent based model on bipartite networks"):
  with members:
    - "emotional reactions and the pulse of public opinion measuring the impact of political events on the sentiment of online discussions"
    - "bloggers behavior and emergent communities in blog space"
    - "measuring the happiness of large scale written expression songs blogs and presidents"

Connected through hyperedge HE-8 (induced by source paper "emotional analysis of blogs and forums data"):
  with members:
    - "bloggers behavior and emergent communities in blog space"
    - "machine learning in automated text categorization"

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.HC(Human-Computer Interaction)