human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge groups authors who co-authored the same paper.

Details of the hypergraph:
Center hyperedge (induced by source paper "Algorithms and applications for approximate nonnegative matrix factorization"):
  Abstract: The development and use of low-rank approximate nonnegative matrix factorization (NMF) algorithms for feature extraction and identification in the fields of text mining and spectral data analysis are presented. The evolution and convergence properties of hybrid methods based on both sparsity and smoothness constraints for the resulting nonnegative matrix factors are discussed. The interpretability of NMF outputs in specific contexts are provided along with opportunities for future work in the modification of NMF algorithms for large-scale and time-varying data sets.

Includes members:
  Member "A Converged Algorithm for Tikhonov Regularized Nonnegative Matrix Factorization with Automatic Regularization Parameters Determination.":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "On the Convergence of Multiplicative Update Algorithms for Nonnegative Matrix Factorization")
  Member "On the Convergence of Multiplicative Update Algorithms for Nonnegative Matrix Factorization":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "Sparse coding of human motion trajectories with non-negative matrix factorization")
  Member "Fast Local Algorithms for Large Scale Nonnegative Matrix and Tensor Factorizations":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "A Fast Hierarchical Alternating Least Squares Algorithm for Orthogonal Nonnegative Matrix Factorization.")
  Member "The Discrete Basis Problem":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "Uncovering hidden structure through parallel problem decomposition")

Question: Please tell me which research area the co-authored paper (i.e., the source paper of the center hyperedge) belongs to. The 4 classes are: Computer science, Mathematics, Engineering, Economics, Psychology, Business. Directly output the class name.

gpt: Mathematics