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: "sponsored search auctions with markovian users"
  Abstract: Sponsored search involves running an auction among advertisers who bid in order to have their ad shown next to search results for specific keywords. Currently, the most popular auction for sponsored search is the "Generalized Second Price" (GSP) auction in which advertisers are assigned to slots in the decreasing order of their "score," which is defined as the product of their bid and click-through rate. In the past few years, there has been significant research on the game-theoretic issues that arise in an advertiser's interaction with the mechanism as well as possible redesigns of the mechanism, but this ranking order has remained standard. #R##N#From a search engine's perspective, the fundamental question is: what is the best assignment of advertisers to slots? Here "best" could mean "maximizing user satisfaction," "most efficient," "revenue-maximizing," "simplest to interact with," or a combination of these. To answer this question we need to understand the behavior of a search engine user when she sees the displayed ads, since that defines the commodity the advertisers are bidding on, and its value. Most prior work has assumed that the probability of a user clicking on an ad is independent of the other ads shown on the page. #R##N#We propose a simple Markovian user model that does not make this assumption. We then present an algorithm to determine the most efficient assignment under this model, which turns out to be different than that of GSP. A truthful auction then follows from an application of the Vickrey-Clarke-Groves (VCG) mechanism. Further, we show that our assignment has many of the desirable properties of GSP that makes bidding intuitive. At the technical core of our result are a number of insights about the structure of the optimal assignment.

Connected through hyperedge HE-1 (induced by source paper "the ad types problem"):
  with members:
    - "sponsored search auctions with rich ads"
    - "note on vcg vs price raising for matching markets"
    - "fast core pricing for rich advertising auctions"
    - "ad auctions and cascade model gsp inefficiency and algorithms"
    - "ironing in the dark"
    - "sponsored search market equilibria and the hungarian method"

Connected through hyperedge HE-2 (induced by source paper "towards better models of externalities in sponsored search auctions"):
  with members:
    - "truthful learning mechanisms for multi slot sponsored search auctions with externalities"
    - "new inapproximability bounds for tsp"
    - "computationally feasible vcg mechanisms"

Connected through hyperedge HE-3 (induced by source paper "price of competition and dueling games"):
  with members:
    - "user satisfaction in competitive sponsored search"

Connected through hyperedge HE-4 (induced by source paper "near optimum online ad allocation for targeted advertising"):
  with members:
    - "online vertex weighted bipartite matching and single bid budgeted allocations"
    - "online stochastic matching online actions based on offline statistics"
    - "online stochastic packing applied to display ad allocation"
    - "online stochastic matching beating 1 1 e"

Connected through hyperedge HE-5 (induced by source paper "combinatorial auctions with conflict based externalities"):
  with members:
    - "secondary spectrum auctions for symmetric and submodular bidders"
    - "approximation algorithms for secondary spectrum auctions"
    - "on the power of randomization in algorithmic mechanism design"

Connected through hyperedge HE-6 (induced by source paper "computational analysis of perfect information position auctions"):
  with members:
    - "graphical models for game theory"
    - "ranking and tradeoffs in sponsored search auctions"
    - "computing nash equilibria of action graph games"
    - "constrained automated mechanism design for infinite games of incomplete information"

Connected through hyperedge HE-7 (induced by source paper "truthful learning mechanisms for multi slot sponsored search auctions with externalities"):
  with members:
    - "optimising trade offs among stakeholders in ad auctions"
    - "regret analysis of stochastic and nonstochastic multi armed bandit problems"
    - "truthful mechanisms with implicit payment computation"
    - "computationally feasible vcg mechanisms"

Connected through hyperedge HE-8 (induced by source paper "online submodular maximization under a matroid constraint with application to learning assignments"):
  with members:
    - "learning policies for contextual submodular prediction"
    - "online learning of assignments that maximize submodular functions"
    - "algorithmic methods for sponsored search advertising"

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.GT(Computer Science and Game Theory)