Statistical Evidence for Three Classes of Gamma-Ray Bursts

@article{Chattopadhyay2007StatisticalEF,
  title={Statistical Evidence for Three Classes of Gamma-Ray Bursts},
  author={Tanuka Chattopadhyay and Ranjeev Misra and Asis Kumar Chattopadhyay and Malay Naskar},
  journal={The Astrophysical Journal},
  year={2007},
  volume={667},
  pages={1017 - 1023}
}
Two different multivariate clustering techniques, the K-means partitioning method and the Dirichlet process of mixture modeling, have been applied to the BATSE gamma-ray burst (GRB) catalog, to obtain the optimum number of coherent groups. In the standard paradigm, GRBs are classified into only two groups, the long and short bursts. However, for both of the clustering techniques, the optimal number of classes was found to be three, a result that is consistent with previous statistical analysis… 

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