source: trunk/yat/statistics/WilcoxonFoldChange.h @ 1486

#ifndef _theplu_yat_statistics_wilcoxonfoldchange_
#define _theplu_yat_statistics_wilcoxonfoldchange_

// $Id: WilcoxonFoldChange.h 1486 2008-09-09 21:17:19Z jari $

/*
  Copyright (C) 2005 Peter Johansson
  Copyright (C) 2006, 2007 Jari Häkkinen, Peter Johansson
  Copyright (C) 2008 Peter Johansson

  This file is part of the yat library, http://dev.thep.lu.se/yat

  The yat library is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 3 of the
  License, or (at your option) any later version.

  The yat library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

#include "Score.h"

namespace theplu {
namespace yat {
  namespace utility {
    class VectorBase;
  }
namespace statistics {

  /**
     @brief WilcoxonFoldChange 
     
     WilcoxonFoldChange is calculated as follows: Having \f$ n_+ \f$
     samples from class + and \f$ n_- \f$ from class -, all \f$ n_+
     n_- \f$ pairwise distances are calculated, and the
     WilcoxonFoldChange is the median of these values.
  */
  class WilcoxonFoldChange : public Score
  {
  public:

    /// 
    /// @brief Default Constructor 
    /// 
    WilcoxonFoldChange(bool absolute=true);

    ///
    /// @return median of all pairwise differences
    ///
    /// @param target defining the two groups (Target.binary() )
    /// @param value vector of the values
    /// 
    double score(const classifier::Target& target, 
                 const utility::VectorBase& value) const; 
 
    /// 
    /// @return weighted median of all pairwise differences
    /// 
    /// For each pair a DataWeight is created with value = value(i) -
    /// value(j) and weight = weight(i)*weight(j) where sample i and
    /// sample j come from different groups.
    ///
    /// @param target defining the two groups 
    /// @param value vector of the values
    /// @param weight vector of accompanied weight to the values
    ///
    /// @note not implemented
    ///
    double score(const classifier::Target& target, 
                 const utility::VectorBase& value, 
                 const utility::VectorBase& weight) const; 
 
  private:

    /// 
    /// @brief Copy Constructor 
    /// 
    WilcoxonFoldChange(const WilcoxonFoldChange&);

    ///
    /// @brief Assignment operator
    ///
    WilcoxonFoldChange& operator=(const WilcoxonFoldChange&);
  };

}}} // of namespace statistics, yat, and theplu

#endif