human: Given a node-centered hypergraph: <hypergraph>, where nodes represent authors and hyperedges represent groups of authors who co-authored the same paper.

Details of the hypergraph:
Center node: "Text-Free User Interfaces for Illiterate and Semi-Literate Users"
  Abstract: We describe work toward the goal of a user interface designed such that even novice, illiterate users require absolutely no intervention from anyone at all to use. Our text-free user interface is based on many hours of ethnographic design conducted in collaboration with a community of illiterate domestic labourers in three Bangalore slums. An ethnographic design process was used to understand what kind of application subjects would be interested in, how they respond to computing technology, and how they react to specific UI elements. We built two applications using these principles, one for job search for domestic labourers, and another for a generic map that could be used for navigating a city. The resulting designs are based on key lessons that we gained through the design process. The paper describes the design process, the design principles which evolved out of the process, the final application design, and results from initial user testing. Our results confirm previous work that emphasizes the need for semi-abstracted graphics and voice feedback, but we additionally find that some aspects of design for illiterate users that have been previously overlooked (such as a consistent help feature). Results also show that the text-free designs are strongly preferred over standard text-based interfaces by the communities which we address, and that they are potentially able to bring even complex computer functions within the reach of users who are unable to read.

Connected through hyperedge HE-1 (induced by source paper "Optimal audio-visual representations for illiterate users of computers"):
  with members:
    (none)

Question: Please tell me which research area the center author belongs to. The 4 classes are: Computer science, Mathematics, Engineering, Economics, Psychology, Business. Directly output the class name.

gpt: Computer science