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: "Classification in the KL-ONE knowledge representation system"
  Abstract: KL-ONE lets one define and use a class of descriptive terms called Concepts, where each Concept denotes a set of objects A subsumption relation between Concepts is defined which is related to set inclusion by way of a semantics for Concepts. This subsumption relation defines a partial order on Concepts, and KL-ONE organizes all Concepts into a taxonomy that reflects this partial order. Classification is a process that takes a new Concept and determines other Concepts that either subsume it or that it subsumes, thereby determining the location for the new Concept within a given taxonomy. We discuss these issues and demonstrate some uses of the classification algorithm.

Connected through hyperedge HE-1 (induced by source paper "Dominance and subsumption in constraint-posting planning"):
  with members:
    - "Representation of decision-theoretic plans as sets of symbolic decision rules"

Connected through hyperedge HE-2 (induced by source paper "Representation and inference in the consul system"):
  with members:
    - "Knowledge acquisition in the consul system"

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: Mathematics