Game Theory

Game Theory (GT) is well-known in economic studies as a theoretical approach to model the strategic interaction between multiple individuals or players in a specific situation. Game Theory approach can also be adopted in the science area to optimize decision-making processes in a strategic setting and often use to solve Multi-Agent RL (MARL) problems.

You can easily access the GT module, as follows:

from fhswf_at_ml.gt.models import *

Some of developed RL frameworks in MLPro can also be reuse in the GT approach. Thus we can just simply inherit some classes from RL frameworks, such as:

1. GameBoard(rl.Environent)

   Since you need a unique utility function for each specific player in the GT approach. A local utility function can be defined as below:

   import fhswf_at_ml.rl.models as rl
   
   class GameBoard(rl.Environment):
       """
       Model class for a game theoretical game board. See super class for more information.
       """
   
       C_TYPE              = 'Game Board'
       C_REWARD_TYPE       = rl.Reward.C_TYPE_EVERY_AGENT
   
       def compute_reward(self) -> rl.Reward:
           if self._last_action is None: return None
   
           reward = rl.Reward(self.get_reward_type())
   
           for player_id in self.last_action.get_agent_ids():
               reward.add_agent_reward(player_id, self._utility_fct(player_id))
   
           return reward
   
       def _utility_fct(self, p_player_id):
           """
           Computes utility of given player. To be redefined.
           """
   
           return 0
   

2. Player(rl.Agent)

   import fhswf_at_ml.rl.models as rl
   
   class Player(rl.Agent):
       """
       This class implements a game theoretical player model. See super class for more information.
       """
   
       C_TYPE      = 'Player'
   

3. Game(rl.Scenario)

   import fhswf_at_ml.rl.models as rl
   
   class Game(rl.Scenario):
       """
       This class implements a game consisting of a game board and a (multi-)player. See super class for
       more information.
       """
   
       C_TYPE      = 'Game'
   

4. MultiPlayer(rl.MultiAgent)

   import fhswf_at_ml.rl.models as rl
   
   class MultiPlayer(rl.MultiAgent):
       """
       This class implements a game theoretical model for a team of players. See super class for more
       information.
       """
   
       C_TYPE      = 'Multi-Player'
   
       def add_player(self, p_player:Player, p_weight=1.0) -> None:
           super().add_agent(p_agent=p_player, p_weight=p_weight)
   

5. Training(rl.Training)

   import fhswf_at_ml.rl.models as rl
   
   class Training(rl.Training):
       """
       This class implements a standardized episodical training process. See super class for more information.
       """
   
       C_NAME      = 'GT'
   

You can check out some of the examples on our how to files or here.