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: "fixed and market pricing for cloud services"
  Abstract: We study a model of congestible resources, where pricing and scheduling are intertwined. Motivated by the problem of pricing cloud instances, we model a cloud computing service as linked $GI/GI/\cdot$ queuing systems where the provider chooses to offer a fixed pricing service, a dynamic market based service, or a hybrid of both, where jobs can be preempted in the market-based service. Users (jobs), who are heterogeneous in both the value they place on service and their cost for waiting, then choose between the services offered. Combining insights from auction theory with queuing theory we are able to characterize user equilibrium behavior, and show its insensitivity to the precise market design mechanism used. We then provide theoretical and simulation based evidence suggesting that a fixed price typically, though not always, generates a higher expected revenue than the hybrid system for the provider.

Connected through hyperedge HE-1 (induced by source paper "a framework for allocating server time to spot and on demand services in cloud computing"):
  with members:
    - "on the benefits of qos differentiated posted pricing in cloud computing an analytical model"
    - "towards designing cost optimal policies to utilize iaas clouds under online learning"
    - "a truthful 1 epsilon optimal mechanism for on demand cloud resource provisioning"
    - "spot pricing in the cloud ecosystem a comparative investigation"
    - "truthful online scheduling with commitments"
    - "algorithms for scheduling deadline sensitive malleable tasks"

Connected through hyperedge HE-2 (induced by source paper "on the cluster admission problem for cloud computing"):
  with members:
    - "overcommitment in cloud services bin packing with chance constraints"
    - "era a framework for economic resource allocation for the cloud"
    - "truthful online scheduling with commitments"
    - "fair allocation without trade"
    - "no justified complaints on fair sharing of multiple resources"
    - "finding approximate pomdp solutions through belief compression"
    - "nonapproximability results for partially observable markov decision processes"

Connected through hyperedge HE-3 (induced by source paper "simple pricing schemes for the cloud"):
  with members:
    - "pricing multi unit markets"
    - "pricing identical items"
    - "revenue gaps for discriminatory and anonymous sequential posted pricing"
    - "prophet inequalities made easy stochastic optimization by pricing non stochastic inputs"
    - "revenue gaps for static and dynamic posted pricing of homogeneous goods"
    - "hiring secretaries over time the benefit of concurrent employment"
    - "on demand or spot selling the cloud to risk averse customers"
    - "truthful online scheduling with commitments"

Connected through hyperedge HE-4 (induced by source paper "era a framework for economic resource allocation for the cloud"):
  with members:
    - "truthful online scheduling with commitments"

Connected through hyperedge HE-5 (induced by source paper "a performance based scheme for pricing resources in the cloud"):
  with members:
    - "a market for scheduling with applications to cloud computing"
    - "random projections for the nonnegative least squares problem"

Connected through hyperedge HE-6 (induced by source paper "using a predator prey model to explain variations of cloud spot price"):
  with members:
    - "spot pricing in the cloud ecosystem a comparative investigation"

Connected through hyperedge HE-7 (induced by source paper "on demand or spot selling the cloud to risk averse customers"):
  with members:
    - "prior independent auctions for risk averse agents"

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)