diff --git a/pyirt/solver/model.py b/pyirt/solver/model.py
index a7d4ccd..5192c0f 100644
--- a/pyirt/solver/model.py
+++ b/pyirt/solver/model.py
@@ -350,8 +350,9 @@ def update(d, start_idx, end_idx):
         else:
             procs = procs_operator(procs, 7200, 0.1)
 
-        for user_idx in tqdm(xrange(num_user)):
+        for user_idx in xrange(num_user):
             self.posterior_theta_distr[user_idx,:] = procs_repo[user_idx]
+        
         # When the loop finish, check if the theta_density adds up to unity for each user
         check_user_distr_marginal = np.sum(self.posterior_theta_distr, axis=1)
         if any(abs(check_user_distr_marginal - 1.0) > 0.0001):
@@ -365,21 +366,52 @@ def __check_theta_density(self):
             raise Exception('theta desnity has wrong shape (%s,%s)'%self.theta_density.shape)
 
     def __get_expect_count(self):
+        def update(d, start_idx, end_idx):
+            try:
+                if self.dao_type == 'db':
+                    client = self.dao.open_conn()
+                    item2user_conn = client[self.dao.db_name][self.dao.item2user_collection_name] 
+                for item_idx in tqdm(xrange(start_idx, end_idx)):
+                    if self.dao_type == 'db':
+                        map_user_idx_vec = self.dao.get_map(item_idx, ['1','0'], item2user_conn)  
+                    else:
+                        map_user_idx_vec = self.dao.get_map(item_idx, ['1','0'])  
+                    d[item_idx] = {
+                            1: np.sum(self.posterior_theta_distr[map_user_idx_vec[0], :], axis=0),
+                            0: np.sum(self.posterior_theta_distr[map_user_idx_vec[1], :], axis=0)
+                            }
+                if self.dao_type == 'db':
+                    client.close()
+            except:
+                raise 
+
+        num_item = self.dao.get_num('item')
+        if num_item > self.num_cpu and self.is_parallel:
+            num_chunk = self.num_cpu
+        else:
+            num_chunk = 1
+
+        # [A] calculate p(data,param|theta)
+        chunk_list = tools.cut_list(num_item, num_chunk)
+        procs = []
+        manager = mp.Manager()
+        procs_repo = manager.dict()
+        for i in range(num_chunk):
+            p = mp.Process(target=update, args=(procs_repo, chunk_list[i][0],chunk_list[i][1],))
+            procs.append(p) 
+        
+        if num_chunk>1: 
+            procs = procs_operator(procs, 5400, self.check_interval)
+        else:
+            procs = procs_operator(procs, 7200, 0.1)
+          
         self.item_expected_right_by_theta = np.zeros((self.num_theta, self.dao.get_num('item')))
         self.item_expected_wrong_by_theta = np.zeros((self.num_theta, self.dao.get_num('item')))
-        num_item = self.dao.get_num('item')
-        if self.dao_type == 'db':
-            client = self.dao.open_conn()
-            item2user_conn = client[self.dao.db_name][self.dao.item2user_collection_name] 
-        for item_idx in tqdm(xrange(num_item)):
-            if self.dao_type == 'db':
-                map_user_idx_vec = self.dao.get_map(item_idx, ['1','0'], item2user_conn)  
-            else:
-                map_user_idx_vec = self.dao.get_map(item_idx, ['1','0'])  
-            self.item_expected_right_by_theta[:, item_idx] = np.sum(self.posterior_theta_distr[map_user_idx_vec[0], :], axis=0)
-            self.item_expected_wrong_by_theta[:, item_idx] = np.sum(self.posterior_theta_distr[map_user_idx_vec[1], :], axis=0)
-        if self.dao_type == 'db':
-            client.close()
+        for item_idx in xrange(num_item):
+            self.item_expected_right_by_theta[:, item_idx] = procs_repo[item_idx][1]
+            self.item_expected_wrong_by_theta[:, item_idx] = procs_repo[item_idx][0]
+
+
 
     def __calc_data_likelihood(self):
         # calculate the likelihood for the data set
@@ -412,6 +444,7 @@ def update(tot_llk, cnt, start_idx, end_idx):
                         tot_llk.value += ell/len(logs)
                     with cnt.get_lock():
                         cnt.value += 1
+
                 if self.dao_type == 'db':
                     client.close()
             except:
@@ -419,27 +452,21 @@ def update(tot_llk, cnt, start_idx, end_idx):
 
         theta_vec  = self.__calc_theta()
         num_user = self.dao.get_num('user')
-
-
         if num_user > self.num_cpu and self.is_parallel:
             num_chunk = self.num_cpu
         else:
-            num_chunk = 1
-        
+            num_chunk = 1 
         user_ell = mp.Value('d', 0.0)  
         user_cnt = mp.Value('i', 0)
-        chunk_list = tools.cut_list(num_user, num_chunk)
-        
+        chunk_list = tools.cut_list(num_user, num_chunk) 
         procs = []
         for i in range(num_chunk):
             p = mp.Process(target=update, args=(user_ell, user_cnt, chunk_list[i][0],chunk_list[i][1],))
-            procs.append(p) 
-        
+            procs.append(p)  
         if num_chunk>1: 
             procs = procs_operator(procs, 1200, self.check_interval)
         else:
             procs = procs_operator(procs, 7200, 0.1)
-
         avg_ell = user_ell.value/user_cnt.value
 
         return avg_ell