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: "on the unhappiness of software developers"
  Abstract: The happy-productive worker thesis states that happy workers are more productive. Recent research in software engineering supports the thesis, and the ideal of flourishing happiness among software developers is often expressed among industry practitioners. However, the literature suggests that a cost-effective way to foster happiness and productivity among workers could be to limit unhappiness. Psychological disorders such as job burnout and anxiety could also be reduced by limiting the negative experiences of software developers. Simultaneously, a baseline assessment of (un)happiness and knowledge about how developers experience it are missing. In this paper, we broaden the understanding of unhappiness among software developers in terms of (1) the software developer population distribution of (un)happiness, and (2) the causes of unhappiness while developing software. We conducted a large-scale quantitative and qualitative survey, incorporating a psychometrically validated instrument for measuring (un)happiness, with 2 220 developers, yielding a rich and balanced sample of 1318 complete responses. Our results indicate that software developers are a slightly happy population, but the need for limiting the unhappiness of developers remains. We also identified 219 factors representing causes of unhappiness while developing software. Our results, which are available as open data, can act as guidelines for practitioners in management positions and developers in general for fostering happiness on the job. We suggest considering happiness in future studies of both human and technical aspects in software engineering.

Connected through hyperedge HE-1 (induced by source paper "time pressure in software engineering a systematic review"):
  with members:
    - "using experience sampling to link software repositories with emotions and work well being"
    - "reviewing literature on time pressure in software engineering and related professions computer assisted interdisciplinary literature review"
    - "bootstrapping a lexicon for emotional arousal in software engineering"
    - "mining valence arousal and dominance possibilities for detecting burnout and productivity"

Connected through hyperedge HE-2 (induced by source paper "challenges in survey research"):
  with members:
    - "empirical software engineering from discipline to interdiscipline"
    - "survey research in software engineering problems and mitigation strategies"
    - "what happens when software developers are un happy"
    - "naming the pain in requirements engineering comparing practices in brazil and germany"
    - "naming the pain in requirements engineering a design for a global family of surveys and first results from germany"

Connected through hyperedge HE-3 (induced by source paper "happiness and the productivity of software engineers"):
  with members:
    - "what happens when software developers are un happy"
    - "how do you feel developer an explanatory theory of the impact of affects on programming performance"
    - "do feelings matter on the correlation of affects and the self assessed productivity in software engineering"
    - "software developers moods emotions and performance"
    - "happy software developers solve problems better psychological measurements in empirical software engineering"

Connected through hyperedge HE-4 (induced by source paper "time pressure in software engineering a systematic literature review"):
  with members:
    - "using experience sampling to link software repositories with emotions and work well being"
    - "reviewing literature on time pressure in software engineering and related professions computer assisted interdisciplinary literature review"
    - "bootstrapping a lexicon for emotional arousal in software engineering"
    - "mining valence arousal and dominance possibilities for detecting burnout and productivity"

Connected through hyperedge HE-5 (induced by source paper "what happens when software developers are un happy"):
  with members:
    - "unhappy developers bad for themselves bad for process and bad for software product"
    - "consequences of unhappiness while developing software"
    - "mining valence arousal and dominance possibilities for detecting burnout and productivity"
    - "understanding the affect of developers theoretical background and guidelines for psychoempirical software engineering"
    - "how do you feel developer an explanatory theory of the impact of affects on programming performance"
    - "the affect of software developers common misconceptions and measurements"
    - "do feelings matter on the correlation of affects and the self assessed productivity in software engineering"
    - "software developers moods emotions and performance"

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.SE(Software Engineering)