Optimal Policies for MDPs: Difference between revisions

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== Parameters ==  
== Parameters ==  


No parameters found.
$n$: number of states


== Table of Algorithms ==  
== Table of Algorithms ==  
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[[File:Optimal Policies for MDPs - Time.png|1000px]]
[[File:Optimal Policies for MDPs - Time.png|1000px]]
== Space Complexity Graph ==
[[File:Optimal Policies for MDPs - Space.png|1000px]]
== Time-Space Tradeoff ==
[[File:Optimal Policies for MDPs - Pareto Frontier.png|1000px]]

Latest revision as of 09:11, 28 April 2023

Description

In an MDP, a policy is a choice of what action to choose at each state An Optimal Policy is a policy where you are always choosing the action that maximizes the “return”/”utility” of the current state. The problem here is to find such an optimal policy from a given MDP.

Parameters

$n$: number of states

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Bellman Value Iteration (VI) 1957 $O({2}^n)$ $O(n)$ Exact Deterministic Time
Howard Policy Iteration (PI) 1960 $O(n^{3})$ $O(n)$ Exact Deterministic Time
Puterman Modified Policy Iteration (MPI) 1974 $O(n^{3})$ $O(n)$ Exact Deterministic

Time Complexity Graph

Optimal Policies for MDPs - Time.png