ALGORITHM 643: FEXACT: a FORTRAN subroutine for Fisher's exact test on unordered r×c contingency tables

  title={ALGORITHM 643: FEXACT: a FORTRAN subroutine for Fisher's exact test on unordered r×c contingency tables},
  author={Cyrus R. Mehta and Nitin R. Patel},
  journal={ACM Trans. Math. Softw.},
The computer code for Mehta and Patel's (1983) network algorithm for Fisher's exact test on unordered r×c contingency tables is provided. The code is written in double precision FORTRAN 77. This code provides the fastest currently available method for executing Fisher's exact test, and is shown to be orders of magnitude superior to any other available algorithm. Many important details of data structures and implementation that have contributed crucially to the success of the network algorithm… 

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