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: "arbitrage opportunities in publication and ghost authors"
  Abstract: In some research evaluation systems, credit awarded to an article depends on the number of co-authors on the article with total credit to the article increasing with the number of co-authors. There are many examples of such evaluation systems (e.g., the United States National Research Council evaluation of graduate programs gave full credit to each co-author). Such credit systems run the risk of encouraging ghost or honorary authorships. In a recent article, Antonio Osorio and Lutz Bornmann (2019) propose a scheme to discourage ghost authorships but increase the total credit to a paper when co-authorships increase. It is shown that if articles are valued more highly as the number of co-authorships increases, then there are opportunities to increase credit by mutually agreeing to add each other as authors. Unrelated authors of unrelated papers may all benefit by expanding their co-author list. I call this phenomena arbitrage--a term borrowed from economics and finance--since the content of the articles do not change, but the value increases by moving to a "market" of more co-authors where articles are valued differently.

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.DL(Digital Libraries)