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: "grand challenges in altmetrics heterogeneity data quality and dependencies"
  Abstract: With increasing uptake among researchers, social media are finding their way into scholarly communication and, under the umbrella term altmetrics, are starting to be utilized in research evaluation. Fueled by technological possibilities and an increasing demand to demonstrate impact beyond the scientific community, altmetrics have received great attention as potential democratizers of the scientific reward system and indicators of societal impact. This paper focuses on the current challenges for altmetrics. Heterogeneity, data quality and particular dependencies are identified as the three major issues and discussed in detail with an emphasis on past developments in bibliometrics. The heterogeneity of altmetrics reflects the diversity of the acts and online events, most of which take place on social media platforms. This heterogeneity has made it difficult to establish a common definition or conceptual framework. Data quality issues become apparent in the lack of accuracy, consistency and replicability of various altmetrics, which is largely affected by the dynamic nature of social media events. Furthermore altmetrics are shaped by technical possibilities and are particularly dependent on the availability of APIs and DOIs, strongly dependent on data providers and aggregators, and potentially influenced by the technical affordances of underlying platforms.

Connected through hyperedge HE-1 (induced by source paper "the stability of twitter metrics a study on unavailable twitter mentions of scientific publications"):
  with members:
    - "scholarly twitter metrics"
    - "social media metrics for new research evaluation"
    - "mendeley readership as a filtering tool to identify highly cited publications"
    - "using almetrics for contextualised mapping of societal impact from hits to networks"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "do altmetrics correlate with citations extensive comparison of altmetric indicators with citations from a multidisciplinary perspective"
    - "tweets as impact indicators examining the implications of automated bot accounts on twitter"
    - "do altmetrics point to the broader impact of research an overview of benefits and disadvantages of altmetrics"

Connected through hyperedge HE-2 (induced by source paper "do altmetrics assess societal impact in a comparable way to case studies an empirical test of the convergent validity of altmetrics based on data from the uk research excellence framework ref"):
  with members:
    - "field and time normalization of data with many zeros an empirical analysis using citation and twitter data"
    - "normalization of zero inflated data an empirical analysis of a new indicator family and its use with altmetrics data"
    - "measuring field normalized impact of papers on specific societal groups an altmetrics study based on mendeley data"
    - "how many scientific papers are mentioned in policy related documents an empirical investigation using web of science and altmetric data"
    - "policy documents as sources for measuring societal impact how often is climate change research mentioned in policy related documents"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "influence of study type on twitter activity for medical research papers"
    - "validity of altmetrics data for measuring societal impact a study using data from altmetric and f1000prime"

Connected through hyperedge HE-3 (induced by source paper "how much research shared on facebook is hidden from public view a comparison of public and private online activity around plos one papers"):
  with members:
    - "interpreting altmetrics viewing acts on social media through the lens of citation and social theories"
    - "distributions for cited articles from individual subjects and years"
    - "tweeting biomedicine an analysis of tweets and citations in the biomedical literature"

Connected through hyperedge HE-4 (induced by source paper "social media metrics for new research evaluation"):
  with members:
    - "on the relationships between bibliographic characteristics of scientific documents and citation and mendeley readership counts a large scale analysis of web of science publications"
    - "towards the social media studies of science social media metrics present and future"
    - "mendeley readership as a filtering tool to identify highly cited publications"
    - "scholars on twitter who and how many are they"
    - "three practical field normalised alternative indicator formulae for research evaluation"
    - "a systematic identification and analysis of scientists on twitter"
    - "t factor a metric for measuring impact on twitter"
    - "iran s scientific dominance and the emergence of south east asian countries as scientific collaborators in the persian gulf region"

Connected through hyperedge HE-5 (induced by source paper "scholarly twitter metrics"):
  with members:
    - "a systematic identification and analysis of scientists on twitter"
    - "botornot a system to evaluate social bots"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "the rise of social bots"
    - "when is an article actually published an analysis of online availability publication and indexation dates"
    - "differences in personal and professional tweets of scholars"
    - "influence of study type on twitter activity for medical research papers"
    - "adapting sentiment analysis for tweets linking to scientific papers"

Connected through hyperedge HE-6 (induced by source paper "author level metrics in the new academic profile platforms the online behaviour of the bibliometrics community"):
  with members:
    - "a novel method for depicting academic disciplines through google scholar citations the case of bibliometrics"
    - "can we use google scholar to identify highly cited documents"
    - "do researchgate scores create ghost academic reputations"
    - "scholars on twitter who and how many are they"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "a review of the characteristics of 108 author level bibliometric indicators"
    - "do altmetrics correlate with citations extensive comparison of altmetric indicators with citations from a multidisciplinary perspective"
    - "do altmetrics point to the broader impact of research an overview of benefits and disadvantages of altmetrics"

Connected through hyperedge HE-7 (induced by source paper "do altmetrics correlate with the quality of papers a large scale empirical study based on f1000prime data"):
  with members:
    - "allegation of scientific misconduct increases twitter attention"
    - "normalization of zero inflated data an empirical analysis of a new indicator family and its use with altmetrics data"
    - "scholarly use of social media and altmetrics a review of the literature"
    - "social media in scholarly communication"
    - "validity of altmetrics data for measuring societal impact a study using data from altmetric and f1000prime"
    - "regression for citation data an evaluation of different methods"
    - "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"

Connected through hyperedge HE-8 (induced by source paper "field and time normalization of data with many zeros an empirical analysis using citation and twitter data"):
  with members:
    - "normalization of zero inflated data an empirical analysis of a new indicator family"
    - "measuring field normalized impact of papers on specific societal groups an altmetrics study based on mendeley data"
    - "three practical field normalised alternative indicator formulae for research evaluation"
    - "national research impact indicators from mendeley readers"
    - "validity of altmetrics data for measuring societal impact a study using data from altmetric and f1000prime"
    - "tweets vs mendeley readers how do these two social media metrics differ"
    - "investigation of partition cells as a structural basis suitable for assessments of individual scientists"
    - "partition based field normalization an approach to highly specialized publication records"

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)