get blending weight by training data

bagging-test/main.cpp

@@ -0,0 +1,128 @@
+#include "github.h"
+
+vector<Rating> data;
+UserList users;
+ItemList items;
+vector<float> nu(USER_NUM, 0);
+map<int,int> test_data;
+
+void postProcessByLanguage(int u, vector< pair<int,float> > & reco){
+     int K = 9;
+     if(reco.size() <= K) return;
+     for(int k = K; k < reco.size(); ++k){
+          int i = reco[k].first;
+          double s1 = 0.01 + sim(users[u].language, items[i].language);
+          double s2 = 0.01 + sim(users[u].repos, items[i].repos);
+          reco[k].second *= s1 * s2;
+     }
+     sort(reco.begin() + K, reco.end(), GreaterSecond<int,float>);
+}
+
+void loadTestData(){
+     ifstream in("../download/removed_values.txt");
+     string line;
+     while(getline(in,line)){
+          line = replace(line, ':', ' ');
+          istringstream iss(line);
+          int uu,ii;
+          iss >> uu >> ii;
+          test_data[uu] = ii;
+     }
+     in.close();
+}
+
+int score(vector< map<int,float> > & reco){
+     int ret = 0;
+     for(map<int,int>::iterator k = test_data.begin(); k != test_data.end(); ++k){
+          vector< pair<int,float> > ru(reco[k->first].begin(), reco[k->first].end());
+          sort(ru.begin(), ru.end(), GreaterSecond<int,float>);
+          for(int i = 0; i < ru.size() && i < 10; ++i){
+               if(ru[i].first == k->second){
+                    ++ret;
+                    break;
+               }
+          }
+     }
+     return ret;
+}
+
+void loadResults(const char * file, vector< map<int,float> > & test){
+     test = vector< map<int,float> >(USER_NUM);
+     string line;
+     ifstream in(file);
+     while(getline(in, line)){
+          istringstream iss(line);
+          int user;
+          iss >> user;
+          int item;
+          float p;
+          while(iss >> item >> p){
+               test[user][item] = p;
+          }
+     }
+     int s = score(test);
+     cout << file << "\t" << s << endl;
+}
+
+int bag(vector< vector< map<int,float> > > & tests, vector<float> & weight){
+     vector< map<int,float> > aa(USER_NUM);
+     for(int k = 0; k < tests.size(); ++k){
+          for(int u = 0; u < tests[k].size(); ++u){
+               if(tests[k][u].empty()) continue;
+               for(map<int,float>::iterator j = tests[k][u].begin(); j != tests[k][u].end(); ++j){
+                    int item = j->first;
+                    if(aa[u].find(item) == aa[u].end()) aa[u][item] = 0;
+                    aa[u][item] += (float)(j->second) * weight[k];
+               }
+          }
+     }
+     ofstream out("result-train.txt");
+     for(int i = 0; i < aa.size(); ++i){
+          if(aa[i].empty()) continue;
+          vector< pair<int,float> > reco(aa[i].begin(), aa[i].end());
+          sort(reco.begin(), reco.end(), GreaterSecond<int,float>);
+          //if(reco.size() > 20) reco.erase(reco.begin() + 20, reco.end());
+          //postProcessByLanguage(i, reco);
+          out << i << ":" << reco[0].first;
+          for(int k = 1; k < reco.size() && k < 20; ++k)
+               out << "," << reco[k].first;
+          out << endl;
+     }
+     out.close();
+     return score(aa);
+}
+
+int main(int argc, char ** argv){
+     loadData(data,true);
+     loadTestData();
+     loadUserItemData(users, items, data);
+     for(int i = 0; i < data.size(); ++i) nu[data[i].user]++;
+#define K 7
+     vector< vector< map<int,float> > > tests(K);
+     vector< float > weight(K);
+     int k = 0;
+     loadResults("../ret2/results-knni-iuf.txt.0", tests[k]); weight[k] = 1; ++k;
+     loadResults("../ret2/results-knnu-iif.txt.0", tests[k]); weight[k] = 1; ++k;
+     loadResults("../ret2/results-knnui.txt.0", tests[k]); weight[k] = 1; ++k;
+     loadResults("../ret2/results-language.txt.0", tests[k]); weight[k] = 0.4; ++k;
+     loadResults("../ret2/results-repos.txt.0", tests[k]); weight[k] = 0.4; ++k;
+     loadResults("../ret2/results-reponame.txt.0", tests[k]); weight[k] = 0.2; ++k;
+     loadResults("../ret2/results-pop-nic.txt.0", tests[k]); weight[k] = 0.01; ++k;
+     srand(time(0));
+     int j = 0;
+     for(int step = 0; step < 20; ++step){
+          int i = j % K;
+          ++j;
+          float w0 = weight[i];
+          int r0 = bag(tests, weight);
+          weight[i] *= (1 + 0.5 * (rand01() - 0.5));
+          int r1 = bag(tests, weight);
+          if(r1 <= r0)
+               weight[i] = w0;
+          cout << step << "\t" << r0 << "\t" << r1 << endl;
+     }
+
+     for(int i = 0; i < weight.size(); ++i) cout << i << "\t" << weight[i] << endl;
+     return 0;
+}
+