HW4!!!

b05902031謝議霆

b05902008王行健

Actor critic VS Policy gradient

Actor critic

Actor critic VS Policy gradient

Algorithm

1. Play a episode with fixed model and get the reward

         - for each state, get (probability, reward)

2. reward = reward * r ^ (t' - t) - baseline

3. ▽J = ▽log(probability) * reward

4. update with ▽J

5. repeat to 1.

Agent at different episode

200 episode

1200 episode

2500 episode

Title Text

Model

1. Play a episode with fixed model and get the reward

         - for each state, get (probability, reward)

2. reward = reward * r ^ (t' - t) - baseline

3. ▽J = ▽log(probability) * reward

4. update with ▽J

5. repeat to 1.

Reward

1. Play a episode with fixed model and get the reward

         - for each state, get (probability, reward)

2. reward = reward * r ^ (t' - t) - baseline

3. ▽J = ▽log(probability) * reward

4. update with ▽J

5. repeat to 1.

state 0 1 2 3 4 5
reward 0 0 0 0 0 -1
modified -0.99^5 -0.99^4 -0.99^3 -0.99^2 -0.99 -1
state 0 1 2 3 4 5
reward 0 0 0 0 0 1
modified 0.99^5 0.99^4 0.99^3 0.99^2 0.99 1

Issue

  • Winning all the time
    • Is it possible to hit every ball?
    • Change the reward with the hitting
  • Rule-based
    • Will model learn such method?
    • True baseline set by TA's
  • How to?

Reward-baseline

1. Play a episode with fixed model and get the reward

         - for each state, get (probability, reward)

2. reward = reward * r ^ (t' - t) - baseline

3. ▽J = ▽log(probability) * reward

4. update with ▽J

5. repeat to 1.

state 0 1 2 3 4 5
reward 0 0 0 0 0 1
modified 0.99^5 0.99^4 0.99^3 0.99^2 0.99 1
normalize -1.4540 -0.8802 -0.3006 0.2849 0.8763 1.4736

DQN VS DDQN

DQN VS Actor critic

Agent at different episode

5000 episode

30000 episode

60000 episode

Title Text

Title Text

DQN Algorithm

1. Play a episode with fixed model and get the reward

         - for each state, get (state, action, state', reward)

         - store in reply buffer

2. sample

3. Compute y = r + 0.99 * max(Q(s', a')) using target network

4. Compute the gradient between y and Q(s, a) using new network

5. update the new network with gradient

6. repeat to 1.

DDQN Algorithm

1. Play a episode with fixed model and get the reward

         - for each state, get (state, action, state', reward)

         - store in reply buffer

2. sample

3. Compute y = r + 0.99 * max(Q'(s', argmax(Q(s', a')))) using current network to output the action

4. Compute the gradient between y and Q(s, a) using new network

5. update the new network with gradient

6. repeat to 1.

Model

deck

By piepie01

deck

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