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 expanding approvals rule improving proportional representation and monotonicity"
  Abstract: Proportional representation (PR) is often discussed in voting settings as a major desideratum. For the past century or so, it is common both in practice and in the academic literature to jump to single transferable vote (STV) as the solution for achieving PR. Some of the most prominent electoral reform movements around the globe are pushing for the adoption of STV. It has been termed a major open problem to design a voting rule that satisfies the same PR properties as STV and better monotonicity properties. In this paper, we first present a taxonomy of proportional representation axioms for general weak order preferences, some of which generalise and strengthen previously introduced concepts. We then present a rule called Expanding Approvals Rule (EAR) that satisfies properties stronger than the central PR axiom satisfied by STV, can handle indifferences in a convenient and computationally efficient manner, and also satisfies better candidate monotonicity properties. In view of this, our proposed rule seems to be a compelling solution for achieving proportional representation in voting settings.

Connected through hyperedge HE-1 (induced by source paper "proportionally representative participatory budgeting with ordinal preferences"):
  with members:
    - "a framework for approval based budgeting methods"
    - "fair allocation of indivisible public goods"
    - "the condorcet principle for multiwinner elections from shortlisting to proportionality"
    - "proportionally representative participatory budgeting axioms and algorithms"
    - "fair mixing the case of dichotomous preferences"
    - "rank maximal equal contribution a probabilistic social choice function"
    - "the core of the participatory budgeting problem"
    - "properties of multiwinner voting rules"

Connected through hyperedge HE-2 (induced by source paper "approximately stable committee selection"):
  with members:
    - "proportionally fair clustering"
    - "group fairness in committee selection"
    - "fair knapsack"
    - "fair allocation of indivisible public goods"
    - "proportionally representative participatory budgeting axioms and algorithms"
    - "the core of the participatory budgeting problem"
    - "properties of multiwinner voting rules"
    - "an improved approximation for k median and positive correlation in budgeted optimization"

Connected through hyperedge HE-3 (induced by source paper "the schulze method of voting"):
  with members:
    - "approval based elections and distortion of voting rules"
    - "a note on the complexity of manipulating weighted schulze voting"
    - "the flow network method"
    - "metric distortion of social choice rules lower bounds and fairness properties"
    - "fault tolerant entity resolution with the crowd"
    - "choosing by means of approval preferential voting the revised approval choice"
    - "how hard is it to control an election by breaking ties"
    - "schulze and ranked pairs voting are fixed parameter tractable to bribe manipulate and control"

Connected through hyperedge HE-4 (induced by source paper "computing and testing pareto optimal committees"):
  with members:
    - "the condorcet principle for multiwinner elections from shortlisting to proportionality"
    - "efficient reallocation under additive and responsive preferences"
    - "properties of multiwinner voting rules"
    - "finding a collective set of items from proportional multirepresentation to group recommendation"
    - "on the computation of fully proportional representation"
    - "the computational complexity of random serial dictatorship"

Connected through hyperedge HE-5 (induced by source paper "representing the insincere strategically robust proportional representation"):
  with members:
    - "how long is a piece of string an exploration of multi winner approval voting and ballot length restrictions"
    - "consistent approval based multi winner rules"
    - "the maximin support method an extension of the d hondt method to approval based multiwinner elections"
    - "achieving fully proportional representation approximability results"

Connected through hyperedge HE-6 (induced by source paper "thresholds quantifying proportionality criteria for election methods"):
  with members:
    - "proportional justified representation"

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)