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add pratio

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This commit is contained in:
tqchen 2014-08-19 08:02:29 -07:00
parent d08d8ed3ed
commit fdba6e9c46
2 changed files with 36 additions and 0 deletions
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35
src/learner/evaluation-inl.hpp
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@ -155,6 +155,41 @@ struct EvalAMS : public IEvaluator {
float ratio_; float ratio_;
}; };
/*! \brief precision with cut off at top percentile */
struct EvalPrecisionRatio : public IEvaluator{
public:
EvalPrecisionRatio( const char *name ) : name_(name) {
utils::Assert(sscanf( name, "apratio@%f", &ratio_) == 1, "BUG");
}
virtual float Eval(const std::vector<float> &preds,
const MetaInfo &info) const {
utils::Assert(preds.size() == info.labels.size(), "label size predict size not match");
std::vector< std::pair<float, unsigned> > rec;
for (size_t j = 0; j < preds.size(); ++j) {
rec.push_back(std::make_pair(preds[j], j));
}
std::sort(rec.begin(), rec.end(), CmpFirst);
double pratio = CalcPRatio( rec, info );
return static_cast<float>(pratio);
}
virtual const char *Name(void) const{
return name_.c_str();
}
protected:
inline double CalcPRatio(const std::vector< std::pair<float,unsigned> >& rec, const MetaInfo &info) const{
size_t cutoff = static_cast<size_t>(ratio_ * rec.size());
double wt_hit = 0.0, wsum = 0.0;
for (size_t j = 0; j < cutoff; ++j) {
wt_hit += info.labels[rec[j].second];
wsum += wt_hit / j;
}
return wsum / cutoff;
}
protected:
float ratio_;
std::string name_;
};
/*! \brief Area under curve, for both classification and rank */ /*! \brief Area under curve, for both classification and rank */
struct EvalAuc : public IEvaluator { struct EvalAuc : public IEvaluator {
virtual float Eval(const std::vector<float> &preds, virtual float Eval(const std::vector<float> &preds,

1
src/learner/evaluation.h
View File

@ -41,6 +41,7 @@ inline IEvaluator* CreateEvaluator(const char *name) {
if (!strcmp(name, "auc")) return new EvalAuc(); if (!strcmp(name, "auc")) return new EvalAuc();
if (!strncmp(name, "ams@", 4)) return new EvalAMS(name); if (!strncmp(name, "ams@", 4)) return new EvalAMS(name);
if (!strncmp(name, "pre@", 4)) return new EvalPrecision(name); if (!strncmp(name, "pre@", 4)) return new EvalPrecision(name);
if (!strncmp(name, "pratio@", 4)) return new EvalPrecisionRatio(name);
if (!strncmp(name, "map", 3)) return new EvalMAP(name); if (!strncmp(name, "map", 3)) return new EvalMAP(name);
if (!strncmp(name, "ndcg", 3)) return new EvalNDCG(name); if (!strncmp(name, "ndcg", 3)) return new EvalNDCG(name);
utils::Error("unknown evaluation metric type: %s", name); utils::Error("unknown evaluation metric type: %s", name);