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add mushroom classification

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tqchen 2014-02-24 22:25:43 -08:00
parent 4aa4faa625
commit 9d6ef11eb5
2 changed files with 26 additions and 3 deletions
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4
demo/mushroom/mushroom.conf
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@ -1,4 +1,4 @@
num_round=10 num_round=2
save_period=0 save_period=0
@ -6,7 +6,7 @@ data = "agaricus.txt.train"
eval[test] = "agaricus.txt.test" eval[test] = "agaricus.txt.test"
booster_type = 0 booster_type = 0
loss_type = 1 loss_type = 2
bst:num_feature=126 bst:num_feature=126
bst:eta=1.0 bst:eta=1.0

25
regression/xgboost_reg.h
View File

@ -172,6 +172,7 @@ namespace xgboost{
enum LossType{ enum LossType{
kLinearSquare = 0, kLinearSquare = 0,
kLogisticNeglik = 1, kLogisticNeglik = 1,
kLogisticClassify = 2
}; };
/*! \brief training parameter for regression */ /*! \brief training parameter for regression */
@ -211,6 +212,7 @@ namespace xgboost{
inline float PredTransform( float x ){ inline float PredTransform( float x ){
switch( loss_type ){ switch( loss_type ){
case kLinearSquare: return x; case kLinearSquare: return x;
case kLogisticClassify:
case kLogisticNeglik: return 1.0f/(1.0f + expf(-x)); case kLogisticNeglik: return 1.0f/(1.0f + expf(-x));
default: utils::Error("unknown loss_type"); return 0.0f; default: utils::Error("unknown loss_type"); return 0.0f;
} }
@ -225,7 +227,8 @@ namespace xgboost{
inline float FirstOrderGradient( float predt, float label ) const{ inline float FirstOrderGradient( float predt, float label ) const{
switch( loss_type ){ switch( loss_type ){
case kLinearSquare: return predt - label; case kLinearSquare: return predt - label;
case 1: return predt - label; case kLogisticClassify:
case kLogisticNeglik: return predt - label;
default: utils::Error("unknown loss_type"); return 0.0f; default: utils::Error("unknown loss_type"); return 0.0f;
} }
} }
@ -238,6 +241,7 @@ namespace xgboost{
inline float SecondOrderGradient( float predt, float label ) const{ inline float SecondOrderGradient( float predt, float label ) const{
switch( loss_type ){ switch( loss_type ){
case kLinearSquare: return 1.0f; case kLinearSquare: return 1.0f;
case kLogisticClassify:
case kLogisticNeglik: return predt * ( 1 - predt ); case kLogisticNeglik: return predt * ( 1 - predt );
default: utils::Error("unknown loss_type"); return 0.0f; default: utils::Error("unknown loss_type"); return 0.0f;
} }
@ -253,6 +257,7 @@ namespace xgboost{
switch( loss_type ){ switch( loss_type ){
case kLinearSquare: return SquareLoss(preds,labels); case kLinearSquare: return SquareLoss(preds,labels);
case kLogisticNeglik: return NegLoglikelihoodLoss(preds,labels); case kLogisticNeglik: return NegLoglikelihoodLoss(preds,labels);
case kLogisticClassify: return ClassificationError(preds, labels);
default: utils::Error("unknown loss_type"); return 0.0f; default: utils::Error("unknown loss_type"); return 0.0f;
} }
} }
@ -284,6 +289,24 @@ namespace xgboost{
ans -= labels[i] * logf(preds[i]) + ( 1 - labels[i] ) * logf(1 - preds[i]); ans -= labels[i] * logf(preds[i]) + ( 1 - labels[i] ) * logf(1 - preds[i]);
return ans; return ans;
} }
/*!
* \brief calculating the ClassificationError loss, given the predictions and labels
* \param preds the given predictions
* \param labels the given labels
* \return the summation of square loss
*/
inline float ClassificationError(const std::vector<float> &preds, const std::vector<float> &labels) const{
int nerr = 0;
for(size_t i = 0; i < preds.size(); i++){
if( preds[i] > 0.5f ){
if( labels[i] < 0.5f ) nerr ++;
}else{
if( labels[i] > 0.5f ) nerr ++;
}
}
return (float)nerr/preds.size();
}
}; };
private: private:
int silent; int silent;