human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "variation in research collaboration patterns across academic ranks"):
  Abstract: The ability to activate and manage effective collaborations is becoming an increasingly important criteria in policies on academic career advancement. The rise of such policies leads to development of indicators that permit measurement of the propensity to collaborate for academics of different ranks, and to examine the role of several variables in collaboration, first among these being the researchers' disciplines. In this work we apply an innovative bibliometric approach based on individual propensity for collaboration to measure the differences in propensity across academic ranks, by discipline and for choice of collaboration forms--intramural, extramural domestic and international. The analysis is based on the scientific production of Italian academics for the period 2006---2010, totaling over 200,000 publications indexed in Web of Science. It shows that assistant professors register a propensity for intramural collaboration that is clearly greater than for professors of higher ranks. Vice versa, the higher ranks, but not quite so clearly, register greater propensity to collaborate at the international level.

Includes members:
  Member "the impact of unproductive and top researchers on overall university research performance":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "comparison of research productivity of italian and norwegian professors and universities")
  Member "the collaboration behaviors of scientists in italy a field level analysis":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "authorship analysis of specialized vs diversified research output")
  Member "gender differences in research collaboration":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "gender disparities in international research collaboration a large scale bibliometric study of 25 000 university professors")
  Member "are researchers that collaborate more at the international level top performers an investigation on the italian university system":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "gender disparities in international research collaboration a large scale bibliometric study of 25 000 university professors")
  Member "a heuristic approach to author name disambiguation in bibliometrics databases for large scale research assessments":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "comparison of research productivity of italian and norwegian professors and universities")
  Member "assessing the varying level of impact measurement accuracy as a function of the citation window length":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "should citations be field normalized in evaluative bibliometrics an empirical analysis based on propensity score matching")
  Member "research productivity are higher academic ranks more productive than lower ones":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "comparison of research productivity of italian and norwegian professors and universities")
  Member "research collaboration and productivity is there correlation":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "an individual level assessment of the relationship between spin off activities and research performance in universities")

Question: Please tell me which class the source paper 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)