function mean = burr_mean ( a, b, c, d )

%*****************************************************************************80
%
%% burr_mean() returns the mean of the Burr PDF.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    08 August 2016
%
%  Author:
%
%    John Burkardt
%
%  Input:
%
%    real A, B, C, D, the parameters of the PDF.
%    0 < B,
%    0 < C.
%
%  Output:
%
%    real MEAN, the mean of the PDF.
%
  ymean = d * beta ( d - 1.0 / c, 1.0 + 1.0 / c );

  mean = a + b * ymean;

  return
end
