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 leiden ranking 2011 2012 data collection indicators and interpretation"
  Abstract: The Leiden Ranking 2011/2012 is a ranking of universities based on bibliometric indicators of publication output, citation impact, and scientific collaboration. The ranking includes 500 major universities from 41 different countries. This paper provides an extensive discussion of the Leiden Ranking 2011/2012. The ranking is compared with other global university rankings, in particular the Academic Ranking of World Universities (commonly known as the Shanghai Ranking) and the Times Higher Education World University Rankings. Also, a detailed description is offered of the data collection methodology of the Leiden Ranking 2011/2012 and of the indicators used in the ranking. Various innovations in the Leiden Ranking 2011/2012 are presented. These innovations include (1) an indicator based on counting a university's highly cited publications, (2) indicators based on fractional rather than full counting of collaborative publications, (3) the possibility of excluding non-English language publications, and (4) the use of stability intervals. Finally, some comments are made on the interpretation of the ranking, and a number of limitations of the ranking are pointed out.

Connected through hyperedge HE-1 (induced by source paper "an evaluation of percentile measures of citation impact and a proposal for making them better"):
  with members:
    - "heuristics as conceptual lens for understanding and studying the usage of bibliometrics in research evaluation"
    - "creativity in science and the link to cited references is the creative potential of papers reflected in their cited references"
    - "plots for visualizing paper impact and journal impact of single researchers in a single graph"
    - "how are excellent highly cited papers defined in bibliometrics a quantitative analysis of the literature"
    - "the substantive and practical significance of citation impact differences between institutions guidelines for the analysis of percentiles using effect sizes and confidence intervals"
    - "methods for the generation of normalized citation impact scores in bibliometrics which method best reflects the judgements of experts"
    - "how to evaluate individual researchers working in the natural and life sciences meaningfully a proposal of methods based on percentiles of citations"
    - "which percentile based approach should be preferred for calculating normalized citation impact values an empirical comparison of five approaches including a newly developed citation rank approach p100"

Connected through hyperedge HE-2 (induced by source paper "should citations be field normalized in evaluative bibliometrics an empirical analysis based on propensity score matching"):
  with members:
    - "the preeminence of ethnic diversity in scientific collaboration"
    - "the geography of references in elite articles which countries contribute to the archives of knowledge"
    - "field normalization of scientometric indicators"
    - "which type of citation analysis generates the most accurate taxonomy of scientific and technical knowledge"
    - "relative citation ratio rcr an empirical attempt to study a new field normalized bibliometric indicator"
    - "validity of basing authors publication strategy on journal impact factors"
    - "a review of theory and practice in scientometrics"
    - "large scale analysis of the accuracy of the journal classification systems of web of science and scopus"

Connected through hyperedge HE-3 (induced by source paper "indicators of open access for universities"):
  with members:
    - "evidence of open access of scientific publications in google scholar a large scale analysis"
    - "developing indicators on open access by combining evidence from diverse data sources"
    - "disentangling gold open access"

Connected through hyperedge HE-4 (induced by source paper "mining university rankings publication output and citation impact as their basis"):
  with members:
    - "a critical comparative analysis of five world university rankings"
    - "what do university rankings by fields rank exploring discrepancies between the organizational structure of universities and bibliometric classifications"
    - "on the internal dynamics of the shanghai ranking"

Connected through hyperedge HE-5 (induced by source paper "research assessment by percentile based double rank analysis"):
  with members:
    - "citation score normalized by cited references csncr the introduction of a new citation impact indicator"
    - "efficiency of research performance and the glass researcher"
    - "identifying potential breakthrough publications using refined citation analyses three related explorative approaches"
    - "a review of the literature on citation impact indicators"
    - "regression for citation data an evaluation of different methods"
    - "how are excellent highly cited papers defined in bibliometrics a quantitative analysis of the literature"
    - "distributions for cited articles from individual subjects and years"
    - "brics countries and scientific excellence a bibliometric analysis of most frequently cited papers"

Connected through hyperedge HE-6 (induced by source paper "the integrated impact indicator i3 revisited a non parametric alternative to the journal impact factor"):
  with members:
    - "discontinuities in citation relations among journals self organized criticality as a model of scientific revolutions and change"
    - "creativity in science and the link to cited references is the creative potential of papers reflected in their cited references"
    - "use of the journal impact factor for assessing individual articles need not be wrong"
    - "can the journal impact factor be used as a criterion for the selection of junior researchers a large scale empirical study based on researcherid data"
    - "citations indicators of quality the impact fallacy"
    - "how are excellent highly cited papers defined in bibliometrics a quantitative analysis of the literature"
    - "the substantive and practical significance of citation impact differences between institutions guidelines for the analysis of percentiles using effect sizes and confidence intervals"
    - "the academic trace of the performance matrix a mathematical synthesis of the h index and the integrated impact indicator i3"

Connected through hyperedge HE-7 (induced by source paper "creativity in science and the link to cited references is the creative potential of papers reflected in their cited references"):
  with members:
    - "core elements in the process of citing publications conceptual overview of the literature"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "a review of the literature on citation impact indicators"
    - "do altmetrics correlate with citations extensive comparison of altmetric indicators with citations from a multidisciplinary perspective"
    - "alternative metrics in scientometrics a meta analysis of research into three altmetrics"
    - "do altmetrics point to the broader impact of research an overview of benefits and disadvantages of altmetrics"
    - "how well developed are altmetrics a cross disciplinary analysis of the presence of alternative metrics in scientific publications"
    - "source normalized indicators of citation impact an overview of different approaches and an empirical comparison"

Connected through hyperedge HE-8 (induced by source paper "core elements in the process of citing publications conceptual overview of the literature"):
  with members:
    - "the number of linked references of publications in microsoft academic in comparison with the web of science"
    - "citation analysis with microsoft academic"
    - "characterizing in text citations in scientific articles a large scale analysis"
    - "the coverage of microsoft academic analyzing the publication output of a university"
    - "excellence networks in science a web based application based on bayesian multilevel logistic regression bmlr for the identification of institutions collaborating successfully"
    - "on the causes of subject specific citation rates in web of science"
    - "what is the effect of country specific characteristics on the research performance of scientific institutions using multi level statistical models to rank and map universities and research focused institutions worldwide"
    - "how to evaluate individual researchers working in the natural and life sciences meaningfully a proposal of methods based on percentiles of citations"

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)