Action space
An action space is the set or structured specification of actions available to an agent in a decision problem or environment.
Evolutionary Deep Learning: Genetic algorithms and neural networks
An action space specifies the set and structure of actions that an agent can take in an environment.
- How it is used
- Defines the choices sampled during exploration or scored during Q-learning and DQN interaction with Gym environments.
- How deep it goes
- Explains discrete action counts through Q-table dimensions, epsilon-greedy selection, and DQN output sizing; defers Q-function detail.
- Examples
- Uses FrozenLake, MountainCar, CartPole, Acrobot, CubeCrash, and LunarLander Gym environments plus random-agent simulations.
- What you can do after
- Apply it via Gym to inspect valid actions, sample exploratory moves, and size Q-tables or DQN output layers.
Read how Evolutionary Deep Learning: Genetic algorithms and neural networks explains action space →
Optimization Algorithms: AI techniques for design, planning, and control problems
An action space is the set of actions available to an agent in an environment.
- How it is used
- Defines the permissible choices an agent can make while learning a policy through environment interaction.
- How deep it goes
- Distinguishes discrete and continuous actions and shows how a discrete action count configures a policy, without detailing space validation.
- Examples
- Uses board-game and robot-control contrasts, then works through CartPole’s left and right actions and actor-network output.
- What you can do after
- Apply it via Gym by reading the action-space size and matching the policy output to the environment’s available actions.
Related concepts
- neuroevolution of augmenting topologiesconfigures · NeuroEvolution of Augmenting Topologies (NEAT) is an evolutionary method that evolves neural-network weights and connection topologies, typically through genomes and speciation.
- tool usageconfigured by · Tool use is an AI system's invocation of external software functions, services, or other capabilities to obtain information or perform actions.
- environmentpart of · An environment is the external context, including its entities and conditions, in which a system, process, or agent exists or operates.
- Q-tableconfigured by · A Q-table is a lookup table storing estimated action values for state-action pairs in a tabular reinforcement-learning system.
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