import random import numpy as np import torch from transformers import AutoModelForSequenceClassification, AutoTokenizer from sklearn.preprocessing import LabelEncoder # Initialize the model and tokenizer model_name = "xlm-roberta-base" tokenizer = AutoTokenizer.from_pretrained(model_name) model = AutoModelForSequenceClassification.from_pretrained(model_name, num_labels=2) # Define action space: [0 = Incorrect, 1 = Correct] action_space = [0, 1] # Define environment (simplified): classify text text_data = [ ("Water freezes at 0°C.", 1), # Correct ("The sun rises in the west.", 0), # Incorrect ("Dogs can fly in the sky.", 0), # Incorrect ("Birds lay eggs.", 1), # Correct ("The Earth is flat.", 0), # Incorrect ] # Q-learning parameters alpha = 0.1 # Learning rate gamma = 0.9 # Discount factor epsilon = 0.1 # Exploration rate n_episodes = 1000 # Number of episodes for training q_table = np.zeros((len(text_data), len(action_space))) # Q-table (state x action) # Reward system (simplified) def get_reward(text, predicted_label): correct_label = next((label for t, label in text_data if t == text), None) if predicted_label == correct_label: return 1 # Reward for correct classification return -1 # Penalty for incorrect classification # Q-learning training loop for episode in range(n_episodes): state = random.choice(text_data) # Random initial text input state_idx = text_data.index(state) # Exploration vs Exploitation if random.uniform(0, 1) < epsilon: action = random.choice(action_space) # Exploration: random action else: action = np.argmax(q_table[state_idx]) # Exploitation: choose best action based on Q-table # Make a prediction based on action inputs = tokenizer(state[0], return_tensors="pt") with torch.no_grad(): output = model(**inputs) predicted_label = torch.argmax(output.logits, dim=1).item() # Get reward from environment reward = get_reward(state[0], predicted_label) # Update Q-table using Q-learning update rule next_state_idx = random.choice(range(len(text_data))) # Random next state (simplified) best_next_action = np.argmax(q_table[next_state_idx]) q_table[state_idx, action] = (1 - alpha) * q_table[state_idx, action] + alpha * (reward + gamma * q_table[next_state_idx, best_next_action]) if episode % 100 == 0: print(f"Episode {episode + 1}/{n_episodes}, Reward: {reward}") # After training, the model should have learned which actions (labels) to take print("Training complete.")