diff --git a/README.md b/README.md
index 5574006..0f2535a 100644
--- a/README.md
+++ b/README.md
@@ -23,9 +23,10 @@ python main.py --target-update 2000 \
                --memory-capacity 100000 \
                --replay-frequency 1 \
                --multi-step 20 \
-               --architecture canonical \
+               --architecture data-efficient \
                --hidden-size 256 \
-               --learning-rate 0.0001
+               --learning-rate 0.0001 \
+               --evaluation-interval 10000
 ```
 
 Requirements
diff --git a/main.py b/main.py
index 82b1d7b..8f1c30d 100644
--- a/main.py
+++ b/main.py
@@ -1,4 +1,6 @@
 import argparse
+from math import inf
+import os
 from datetime import datetime
 import atari_py
 import numpy as np
@@ -13,6 +15,7 @@
 
 # Note that hyperparameters may originally be reported in ATARI game frames instead of agent steps
 parser = argparse.ArgumentParser(description='Rainbow')
+parser.add_argument('--id', type=str, default='default', help='Experiment ID')
 parser.add_argument('--seed', type=int, default=123, help='Random seed')
 parser.add_argument('--disable-cuda', action='store_true', help='Disable CUDA')
 parser.add_argument('--game', type=str, default='space_invaders', choices=atari_py.list_games(), help='ATARI game')
@@ -51,6 +54,9 @@
 print(' ' * 26 + 'Options')
 for k, v in vars(args).items():
   print(' ' * 26 + k + ': ' + str(v))
+results_dir = os.path.join('results', args.id)
+os.makedirs(results_dir, exist_ok=True)
+metrics = {'steps': [], 'rewards': [], 'Qs': [], 'best_avg_reward': -inf}
 np.random.seed(args.seed)
 torch.manual_seed(np.random.randint(1, 10000))
 if torch.cuda.is_available() and not args.disable_cuda:
@@ -92,7 +98,7 @@ def log(s):
 
 if args.evaluate:
   dqn.eval()  # Set DQN (online network) to evaluation mode
-  avg_reward, avg_Q = test(args, 0, dqn, val_mem, evaluate=True)  # Test
+  avg_reward, avg_Q = test(args, 0, dqn, val_mem, metrics, results_dir, evaluate=True)  # Test
   print('Avg. reward: ' + str(avg_reward) + ' | Avg. Q: ' + str(avg_Q))
 else:
   # Training loop
@@ -120,7 +126,7 @@ def log(s):
 
       if T % args.evaluation_interval == 0:
         dqn.eval()  # Set DQN (online network) to evaluation mode
-        avg_reward, avg_Q = test(args, T, dqn, val_mem)  # Test
+        avg_reward, avg_Q = test(args, T, dqn, val_mem, metrics, results_dir)  # Test
         log('T = ' + str(T) + ' / ' + str(args.T_max) + ' | Avg. reward: ' + str(avg_reward) + ' | Avg. Q: ' + str(avg_Q))
         dqn.train()  # Set DQN (online network) back to training mode
 
diff --git a/test.py b/test.py
index 8184e56..0b20f0c 100644
--- a/test.py
+++ b/test.py
@@ -7,16 +7,11 @@
 from env import Env
 
 
-# Globals
-Ts, rewards, Qs, best_avg_reward = [], [], [], -1e10
-
-
 # Test DQN
-def test(args, T, dqn, val_mem, evaluate=False):
-  global Ts, rewards, Qs, best_avg_reward
+def test(args, T, dqn, val_mem, metrics, results_dir, evaluate=False):
   env = Env(args)
   env.eval()
-  Ts.append(T)
+  metrics['steps'].append(T)
   T_rewards, T_Qs = [], []
 
   # Test performance over several episodes
@@ -43,18 +38,19 @@ def test(args, T, dqn, val_mem, evaluate=False):
 
   avg_reward, avg_Q = sum(T_rewards) / len(T_rewards), sum(T_Qs) / len(T_Qs)
   if not evaluate:
-    # Append to results
-    rewards.append(T_rewards)
-    Qs.append(T_Qs)
+    # Save model parameters if improved
+    if avg_reward > metrics['best_avg_reward']:
+      metrics['best_avg_reward'] = avg_reward
+      dqn.save(results_dir)
 
-    # Plot
-    _plot_line(Ts, rewards, 'Reward', path='results')
-    _plot_line(Ts, Qs, 'Q', path='results')
+    # Append to results and save metrics
+    metrics['rewards'].append(T_rewards)
+    metrics['Qs'].append(T_Qs)
+    torch.save(metrics, os.path.join(results_dir, 'metrics.pth'))
 
-    # Save model parameters if improved
-    if avg_reward > best_avg_reward:
-      best_avg_reward = avg_reward
-      dqn.save('results')
+    # Plot
+    _plot_line(metrics['steps'], metrics['rewards'], 'Reward', path=results_dir)
+    _plot_line(metrics['steps'], metrics['Qs'], 'Q', path=results_dir)
 
   # Return average reward and Q-value
   return avg_reward, avg_Q