tScore.h

#ifndef _theplu_yat_statistics_tscore_
#define _theplu_yat_statistics_tscore_ 

// $Id: tScore.h 2119 2009-12-12 23:11:43Z peter $

/*
  Copyright (C) 2004, 2005 Peter Johansson
  Copyright (C) 2006 Jari Häkkinen, Peter Johansson, Markus Ringnér
  Copyright (C) 2007, 2008 Jari Häkkinen, 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 yat. If not, see <http://www.gnu.org/licenses/>.
*/

#include "Score.h"

#include <cmath>
#include <gsl/gsl_cdf.h>

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

  class tScore : public Score
  {
  
  public:
    tScore(bool absolute=true);

    
    double score(const classifier::Target& target, 
                 const utility::VectorBase& value) const; 

    double score(const classifier::Target& target, 
                 const utility::VectorBase& value, double* dof) const; 

    double score(const classifier::Target& target, 
                 const classifier::DataLookupWeighted1D& value,
                 double* dof=0) const; 

    double score(const classifier::Target& target, 
                 const classifier::DataLookupWeighted1D& value) const; 

    double score(const classifier::Target& target, 
                 const utility::VectorBase& value, 
                 const utility::VectorBase& weight) const; 

    double score(const classifier::Target& target, 
                 const utility::VectorBase& value, 
                 const utility::VectorBase& weight,
                 double* dof=0) const; 

    template<typename T1, typename T2> 
    double score(const T1& pos, const T2& neg, double* dof=0) const;

  private:
    
  };

  template<typename T1, typename T2> 
  double tScore::score(const T1& pos, const T2& neg, double* dof) const
  {
    double diff = pos.mean() - neg.mean();
    if (dof)
      *dof=pos.n()+neg.n()-2;
    double s2=( (pos.sum_xx_centered()+neg.sum_xx_centered())/
                (pos.n()+neg.n()-2));
    double t=diff/sqrt(s2/pos.n()+s2/neg.n());
    if (t<0 && absolute_)
      return -t;
    return t;
  }

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

#endif