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: "On the evocative power and play value of a wearable movement-to-sound interaction accessory in the free-play of schoolchildren"
  Abstract: This paper discusses the evocative power and play value of the Wearable Sounds Kit WSK, a movement-to-sound interaction accessory. Whilst movement-to-sound interaction is attracting growing research attention in HCI, very little of it has been conducted in the context of free-play with children. This paper presents a participatory design study of the WSK with 20 school-aged children 7--12 years old in a free-play scenario, and an evaluation of the WSK in a playground at Ars Electronica Festival with over 70 school-aged children. The evaluation addressed three research questions: can school-aged children incorporate the WSK into their free-play? What free-play patterns are encouraged by the WSK? Which design features of the WSK influence the free-play experience? By conducting qualitative and quantitative data gathering methods and analyses, which include first-hand observations and video-coding, this paper shows that school-aged children can effectively incorporate the WSK into their free-play, and that the accessory encourages different types of free-play. The results also show differences in the free-play mediated by the accessory depending on the age group and sex of the player, and these differences reinforce the play value of the WSK. Some implications for designing technologically-oriented playful toys are also discussed.

Connected through hyperedge HE-1 (induced by source paper "Aerial tunes: exploring interaction qualities of mid-air displays"):
  with members:
    - "LinkLights: a modular, user adaptable system to support rehabilitation practices"

Connected through hyperedge HE-2 (induced by source paper "The Things We Play with Roles of Technology in Social Play"):
  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