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: "the groupon effect on yelp ratings a root cause analysis"
  Abstract: Daily deals sites such as Groupon offer deeply discounted goods and services to tens of millions of customers through geographically targeted daily e-mail marketing campaigns. In our prior work we observed that a negative side effect for merchants using Groupons is that, on average, their Yelp ratings decline significantly. However, this previous work was essentially observational, rather than explanatory. In this work, we rigorously consider and evaluate various hypotheses about underlying consumer and merchant behavior in order to understand this phenomenon, which we dub the Groupon effect. We use statistical analysis and mathematical modeling, leveraging a dataset we collected spanning tens of thousands of daily deals and over 7 million Yelp reviews. In particular, we investigate hypotheses such as whether Groupon subscribers are more critical than their peers, or whether some fraction of Groupon merchants provide significantly worse service to customers using Groupons. We suggest an additional novel hypothesis: reviews from Groupon subscribers are lower on average because such reviews correspond to real, unbiased customers, while the body of reviews on Yelp contain some fraction of reviews from biased or even potentially fake sources. Although we focus on a specific question, our work provides broad insights into both consumer and merchant behavior within the daily deals marketplace.

Connected through hyperedge HE-1 (induced by source paper "contextual centrality going beyond network structures"):
  with members:
    - "targeting interventions in networks"
    - "online influence maximization under independent cascade model with semi bandit feedback"
    - "submodular optimization with submodular cover and submodular knapsack constraints"
    - "the slashdot zoo mining a social network with negative edges"

Connected through hyperedge HE-2 (induced by source paper "the status gradient of trends in social media"):
  with members:
    - "all who wander on the prevalence and characteristics of multi community engagement"
    - "from amateurs to connoisseurs modeling the evolution of user expertise through online reviews"

Connected through hyperedge HE-3 (induced by source paper "designing markets for daily deals"):
  with members:
    - "daily deals prediction social diffusion and reputational ramifications"
    - "eliciting forecasts from self interested experts scoring rules for decision makers"

Connected through hyperedge HE-4 (induced by source paper "optimal groupon allocations"):
  with members:
    - "daily deals prediction social diffusion and reputational ramifications"

Connected through hyperedge HE-5 (induced by source paper "real time bid optimization for group buying ads"):
  with members:
    - "daily deals prediction social diffusion and reputational ramifications"
    - "selective call out and real time bidding"
    - "bidding for representative allocations for display advertising"

Connected through hyperedge HE-6 (induced by source paper "does a daily deal promotion signal a distressed business an empirical investigation of small business survival"):
  with members:
    - "daily deals prediction social diffusion and reputational ramifications"

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.SI(Social and Information Networks)