could skip sequence (p=0.5)

models.py

@@ -76,6 +76,23 @@ def bpr_max_loss(p_scores, n_values,device):
     loss = loss.sum()
     return loss
 
+def bpr_max_loss_regularized(p_scores, n_values,device,l=0.0001):
+    s = F.softmax(n_values,dim=1)
+    ratio = int(n_values.shape[1] / p_scores.shape[1])
+    temp_pvalues = torch.tensor([],device=device)
+    for i in range(p_scores.shape[1]):
+        temp_pvalues = torch.cat((temp_pvalues,p_scores[:,i,None].expand(-1,ratio)),dim=1)
+
+    d = torch.sigmoid(torch.sub(temp_pvalues,n_values))
+    t = torch.mul(s,d)
+    loss = -1 * torch.log(t.sum(dim=1))
+    loss = loss.sum()
+
+    loss2 = torch.mul(s,n_values**2)
+    loss2 = loss2.sum(dim=1)
+    loss2 = loss2.sum()
+    return loss + l*loss2
+
 def top_loss(p_scores, n_values,device):
     ratio = int(n_values.shape[1] / p_scores.shape[1])
     temp_pvalues = torch.tensor([],device=device)
@@ -107,6 +124,7 @@ class MetaTL(nn.Module):
 
         self.embedding_learner = EmbeddingLearner()
         # self.loss_func = nn.MarginRankingLoss(self.margin)
+        # self.loss_func = bpr_max_loss
         self.loss_func = bpr_loss
 
         self.rel_q_sharing = dict()

sampler.py

@@ -12,8 +12,8 @@ def random_neq(l, r, s, user_train,usernum):
     # while t in s:
     #     t = np.random.randint(l, r)
     # return t
-    user = np.random.randint(1, usernum + 1)
-    candid_item = user_train[user][np.random.randint(0,len(user_train[user]))]
+    user = np.random.choice(1, usernum + 1)
+    candid_item = user_train[user][np.random.randint(0, len(user_train[user]))]
 
     while candid_item in s:
         user = np.random.randint(1, usernum + 1)
@@ -21,14 +21,23 @@ def random_neq(l, r, s, user_train,usernum):
     return candid_item
 
 
+def random_negetive_batch(l, r, s, user_train,usernum, batch_users):
+    user = np.random.choice(batch_users)
+    candid_item = user_train[user][np.random.randint(0, len(user_train[user]))]
+
+    while candid_item in s:
+        user = np.random.choice(batch_users)
+        candid_item = user_train[user][np.random.randint(0, len(user_train[user]))]
+    return candid_item
+
+
 def sample_function_mixed(user_train, usernum, itemnum, batch_size, maxlen, result_queue, SEED,number_of_neg):
-    def sample():
 
-        if random.random()<=1:
-            user = np.random.randint(1, usernum + 1)
-            while len(user_train[user]) <= 1: user = np.random.randint(1, usernum + 1)
+    def sample(user,batch_users):
+        if random.random()<=0.5:
+            # user = np.random.randint(1, usernum + 1)
+            # while len(user_train[user]) <= 1: user = np.random.randint(1, usernum + 1)
 
-            
             seq = np.zeros([maxlen], dtype=np.int32)
             pos = np.zeros([maxlen], dtype=np.int32)
             neg = np.zeros([maxlen*number_of_neg], dtype=np.int32)
@@ -51,7 +60,8 @@ def sample_function_mixed(user_train, usernum, itemnum, batch_size, maxlen, resu
                 if idx == -1: break
 
             for i in range(len(neg)):
-                neg[i] = random_neq(1, itemnum + 1, ts, user_train,usernum)
+                # neg[i] = random_neq(1, itemnum + 1, ts, user_train,usernum)
+                neg[i] = random_negetive_batch(1, itemnum + 1, ts, user_train, usernum, batch_users = batch_users)
 
             curr_rel = user
             support_triples, support_negative_triples, query_triples, negative_triples = [], [], [], []
@@ -72,12 +82,13 @@ def sample_function_mixed(user_train, usernum, itemnum, batch_size, maxlen, resu
             return support_triples, support_negative_triples, query_triples, negative_triples, curr_rel
 
         else:
-            user = np.random.randint(1, usernum + 1)
-            while len(user_train[user]) <= 1: user = np.random.randint(1, usernum + 1)
+            # print("bug happened in sample_function_mixed")
+            # user = np.random.randint(1, usernum + 1)
+            # while len(user_train[user]) <= 1: user = np.random.randint(1, usernum + 1)
 
             seq = np.zeros([maxlen], dtype=np.int32)
             pos = np.zeros([maxlen], dtype=np.int32)
-            neg = np.zeros([maxlen], dtype=np.int32)
+            neg = np.zeros([maxlen*number_of_neg], dtype=np.int32)
 
             list_idx = random.sample([i for i in range(len(user_train[user]))], maxlen + 1)
             list_item = [user_train[user][i] for i in sorted(list_idx)]
@@ -89,16 +100,25 @@ def sample_function_mixed(user_train, usernum, itemnum, batch_size, maxlen, resu
             for i in reversed(list_item[:-1]):
                 seq[idx] = i
                 pos[idx] = nxt
-                if nxt != 0: neg[idx] = random_neq(1, itemnum + 1, ts)
+                # if nxt != 0: neg[idx] = random_neq(1, itemnum + 1, ts)
                 nxt = i
                 idx -= 1
                 if idx == -1: break
 
             curr_rel = user
             support_triples, support_negative_triples, query_triples, negative_triples = [], [], [], []
+
+            for i in range(len(neg)):
+                # neg[i] = random_neq(1, itemnum + 1, ts, user_train,usernum)
+                neg[i] = random_negetive_batch(1, itemnum + 1, ts, user_train, usernum, batch_users = batch_users)
+
+            for j in range(number_of_neg):
+                for idx in range(maxlen-1):
+                    support_negative_triples.append([seq[idx], curr_rel, neg[j*maxlen + idx]])
+
             for idx in range(maxlen-1):
                 support_triples.append([seq[idx],curr_rel,pos[idx]])
-                support_negative_triples.append([seq[idx],curr_rel,neg[idx]])
+                # support_negative_triples.append([seq[idx],curr_rel,neg[idx]])
             query_triples.append([seq[-1],curr_rel,pos[-1]])
             negative_triples.append([seq[-1],curr_rel,neg[-1]])
 
@@ -108,8 +128,15 @@ def sample_function_mixed(user_train, usernum, itemnum, batch_size, maxlen, resu
     
     while True:
         one_batch = []
+
+        users = []
+        for i in range(batch_size):
+            user = np.random.randint(1, usernum + 1)
+            while len(user_train[user]) <= 1: user = np.random.randint(1, usernum + 1)
+            users.append(user)
+
         for i in range(batch_size):
-            one_batch.append(sample())
+            one_batch.append(sample(user = users[i], batch_users = users))
 
         support, support_negative, query, negative, curr_rel = zip(*one_batch)