# Optimistic Linear Support and Successor Features as a Basis for Optimal Policy Transfer

arXiv: https://arxiv.org/abs/2206.11326 · HTML: https://mlsanity.com/paper/2206.11326/

## Key facts

- Cited by 22 papers in the map (data through 14 Oct 2026).
- Builds on 24 of its 48 references that are in the map.
- First posted on arXiv 22 Jun 2022.

## Builds on (most cited first, 24 of 24)

- [Adam: A Method for Stochastic Optimization](https://mlsanity.com/paper/1412.6980/) (2014)
- [Deep Reinforcement Learning with Double Q-learning](https://mlsanity.com/paper/1509.06461/) (2015)
- [Prioritized Experience Replay](https://mlsanity.com/paper/1511.05952/) (2015)
- [Diversity is All You Need: Learning Skills without a Reward Function](https://mlsanity.com/paper/1802.06070/) (2018)
- [CVXPY: A Python-Embedded Modeling Language for Convex Optimization](https://mlsanity.com/paper/1603.00943/) (2016)
- [Successor Features for Transfer in Reinforcement Learning](https://mlsanity.com/paper/1606.05312/) (2016)
- [Variational Intrinsic Control](https://mlsanity.com/paper/1611.07507/) (2016)
- [A Practical Guide to Multi-Objective Reinforcement Learning and Planning](https://mlsanity.com/paper/2103.09568/) (2021)
- [A Survey of Multi-Objective Sequential Decision-Making](https://mlsanity.com/paper/1402.0590/) (2014)
- [A Generalized Algorithm for Multi-Objective Reinforcement Learning and Policy Adaptation](https://mlsanity.com/paper/1908.08342/) (2019)
- [Fast Task Inference with Variational Intrinsic Successor Features](https://mlsanity.com/paper/1906.05030/) (2019)
- [APS: Active Pretraining with Successor Features](https://mlsanity.com/paper/2108.13956/) (2021)
- [Universal Successor Features Approximators](https://mlsanity.com/paper/1812.07626/) (2018)
- [Dynamic Weights in Multi-Objective Deep Reinforcement Learning](https://mlsanity.com/paper/1809.07803/) (2018)
- [Transfer in Deep Reinforcement Learning Using Successor Features and Generalised Policy Improvement](https://mlsanity.com/paper/1901.10964/) (2019)
- [Multi-Objective Deep Reinforcement Learning](https://mlsanity.com/paper/1610.02707/) (2016)
- [Scalar reward is not enough: A response to Silver, Singh, Precup and Sutton (2021)](https://mlsanity.com/paper/2112.15422/) (2021)
- [A Boolean Task Algebra for Reinforcement Learning](https://mlsanity.com/paper/2001.01394/) (2020)
- [An Equivalence between Loss Functions and Non-Uniform Sampling in Experience Replay](https://mlsanity.com/paper/2007.06049/) (2020)
- [The Information Geometry of Unsupervised Reinforcement Learning](https://mlsanity.com/paper/2110.02719/) (2021)
- [Discovering a set of policies for the worst case reward](https://mlsanity.com/paper/2102.04323/) (2021)
- [Discovering Diverse Nearly Optimal Policies with Successor Features](https://mlsanity.com/paper/2106.00669/) (2021)
- [Constructing a Good Behavior Basis for Transfer using Generalized Policy Updates](https://mlsanity.com/paper/2112.15025/) (2021)
- [Risk-Aware Transfer in Reinforcement Learning using Successor Features](https://mlsanity.com/paper/2105.14127/) (2021)

## Built on by (most cited first, 22 of 22)

- [Sample-Efficient Multi-Objective Learning via Generalized Policy Improvement Prioritization](https://mlsanity.com/paper/2301.07784/) (2023)
- [Proto Successor Measure: Representing the Behavior Space of an RL Agent](https://mlsanity.com/paper/2411.19418/) (2024)
- [Learning Successor Features the Simple Way](https://mlsanity.com/paper/2410.22133/) (2024)
- [Task Adaptation from Skills: Information Geometry, Disentanglement, and New Objectives for Unsupervised Reinforcement Learning](https://mlsanity.com/paper/2506.10629/) (2025)
- [Utility-Based Reinforcement Learning: Unifying Single-objective and Multi-objective Reinforcement Learning](https://mlsanity.com/paper/2402.02665/) (2024)
- [Predictive representations: building blocks of intelligence](https://mlsanity.com/paper/2402.06590/) (2024)
- [Planning with a Learned Policy Basis to Optimally Solve Complex Tasks](https://mlsanity.com/paper/2403.15301/) (2024)
- [C-MORL: Multi-Objective Reinforcement Learning through Efficient Discovery of Pareto Front](https://mlsanity.com/paper/2410.02236/) (2024)
- [Scalable Multi-Objective Reinforcement Learning with Fairness Guarantees using Lorenz Dominance](https://mlsanity.com/paper/2411.18195/) (2024)
- [Safety-Constrained Policy Transfer with Successor Features](https://mlsanity.com/paper/2211.05361/) (2022)
- [Demonstration Guided Multi-Objective Reinforcement Learning](https://mlsanity.com/paper/2404.03997/) (2024)
- [A Meta-Learning Approach for Multi-Objective Reinforcement Learning in Sustainable Home Environments](https://mlsanity.com/paper/2407.11489/) (2024)
- [QuietPaw: Learning Quadrupedal Locomotion with Versatile Noise Preference Alignment](https://mlsanity.com/paper/2503.05035/) (2025)
- [Constructing an Optimal Behavior Basis for the Option Keyboard](https://mlsanity.com/paper/2505.00787/) (2025)
- [A Reward-Free Viewpoint on Multi-Objective Reinforcement Learning](https://mlsanity.com/paper/2604.24532/) (2026)
- [Uncertainty-aware transfer across tasks using hybrid model-based successor feature reinforcement learning](https://mlsanity.com/paper/2310.10818/) (2023)
- [Reward-Conditioned Reinforcement Learning](https://mlsanity.com/paper/2603.05066/) (2026)
- [Interpretability by Design for Efficient Multi-Objective Reinforcement Learning](https://mlsanity.com/paper/2506.04022/) (2025)
- [Limitations of Scalarisation in MORL: A Comparative Study in Discrete Environments](https://mlsanity.com/paper/2511.16476/) (2025)
- [The Terminal Representation in Reinforcement Learning](https://mlsanity.com/paper/2605.31289/) (2026)
- [Is Per-Agent Policy Composition Safe? Rethinking Successor-Feature Transfer in Cooperative Multi-Agent Reinforcement Learning](https://mlsanity.com/paper/2608.11658/) (2026)
- [It's a matter of timescale: non-linear utility in successor features and multi-objective planning and learning](https://mlsanity.com/paper/2608.25723/) (2026)

## Abstract (arXiv)

In many real-world applications, reinforcement learning (RL) agents might have to solve multiple tasks, each one typically modeled via a reward function. If reward functions are expressed linearly, and the agent has previously learned a set of policies for different tasks, successor features (SFs) can be exploited to combine such policies and identify reasonable solutions for new problems. However, the identified solutions are not guaranteed to be optimal. We introduce a novel algorithm that addresses this limitation. It allows RL agents to combine existing policies and directly identify optimal policies for arbitrary new problems, without requiring any further interactions with the environment. We first show (under mild assumptions) that the transfer learning problem tackled by SFs is equivalent to the problem of learning to optimize multiple objectives in RL. We then introduce an SF-based extension of the Optimistic Linear Support algorithm to learn a set of policies whose SFs form a convex coverage set. We prove that policies in this set can be combined via generalized policy improvement to construct optimal behaviors for any new linearly-expressible tasks, without requiring any additional training samples. We empirically show that our method outperforms state-of-the-art competing algorithms both in discrete and continuous domains under value function approximation.
