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: "notes on the existence of a solution in the pairwise comparisons method using the heuristic rating estimation approach"
  Abstract: Pairwise comparisons (PC) is a well-known method for modeling the subjective preferences of a decision maker. The method is very often used in the models of voting systems, social choice theory, decision techniques (such as AHP - Analytic Hierarchy Process) or multi-agent AI systems. In this approach, a set of paired comparisons is transformed into one overall ranking of alternatives. Very often, only the results of individual comparisons are given, whilst the weights (indicators of significance) of the alternatives need to be computed. According to Heuristic Rating Estimation (HRE), the new approach discussed in the article, besides the results of comparisons, the weights of some alternatives can also be a priori known. Although HRE uses a similar method to the popular AHP technique to compute the weights of individual alternatives, the solution obtained is not always positive and real. This article tries to answer the question of when such a correct solution exists. Hence, the sufficient condition for the existence of a positive and real solution in the HRE approach is formulated and proven. The influence of inconsistency in the paired comparisons set for the existence of a solution is also discussed.

Connected through hyperedge HE-1 (induced by source paper "inconsistency indices for incomplete pairwise comparisons matrices"):
  with members:
    - "on the geometric mean method for incomplete pairwise comparisons"
    - "inconsistency in the ordinal pairwise comparisons method with and without ties"
    - "new results on inconsistency indices and their relationship with the quality of priority vector estimation"
    - "recent advances on inconsistency indices for pairwise comparisons a commentary"
    - "axiomatic properties of inconsistency indices for pairwise comparisons"
    - "on the properties of the priority deriving procedure in the pairwise comparisons method"
    - "on axiomatization of inconsistency indicators for pairwise comparisons"

Connected through hyperedge HE-2 (induced by source paper "towards quantification of incompleteness in the pairwise comparisons method"):
  with members:
    - "inconsistency in the ordinal pairwise comparisons method with and without ties"
    - "on axiomatization of inconsistency indicators for pairwise comparisons"

Connected through hyperedge HE-3 (induced by source paper "heuristic rating estimation geometric approach"):
  with members:
    - "axiomatic properties of inconsistency indices for pairwise comparisons"
    - "heuristic rating estimation approach to the pairwise comparisons method"
    - "on distance based inconsistency reduction algorithms for pairwise comparisons"

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.DM(Discrete Mathematics)