actions
One such method is 



ε


{\displaystyle \varepsilon }

-greedy, where 



0
<
ε
<
1


{\displaystyle 0<\varepsilon <1}

 is a parameter controlling the amount of exploration vs. exploitation.  With probability 



1
−
ε


{\displaystyle 1-\varepsilon }

, exploitation is chosen, and the agent chooses the action that it believes has the best long-term effect (ties between actions are broken uniformly at random). Alternatively, with probability 



ε


{\displaystyle \varepsilon }

, exploration is chosen, and the action is chosen uniformly at random. 



ε


{\displaystyle \varepsilon }

 is usually a fixed parameter but can be adjusted either according to a schedule (making the agent explore progressively less), or adaptively based on heuristics.
