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Found 22 papers, 2 papers with code
Multi-IF: Benchmarking LLMs on Multi-Turn and Multilingual Instructions Following
To address this gap, we introduce Multi-IF, a new benchmark designed to assess LLMs' proficiency in following multi-turn and multilingual instructions.
The Perfect Blend: Redefining RLHF with Mixture of Judges
However, RLHF has limitations in multi-task learning (MTL) due to challenges of reward hacking and extreme multi-objective optimization (i. e., trade-off of multiple and/or sometimes conflicting objectives).
Provably Efficient Offline Reinforcement Learning with Trajectory-Wise Reward
The remarkable success of reinforcement learning (RL) heavily relies on observing the reward of every visited state-action pair.
Model-Based Offline Meta-Reinforcement Learning with Regularization
In particular, we devise a new meta-Regularized model-based Actor-Critic (RAC) method for within-task policy optimization, as a key building block of MerPO, using conservative policy evaluation and regularized policy improvement; and the intrinsic tradeoff therein is achieved via striking the right balance between two regularizers, one based on the behavior policy and the other on the meta-policy.
Faster Algorithm and Sharper Analysis for Constrained Markov Decision Process
Despite the challenge of the nonconcave objective subject to nonconcave constraints, the proposed approach is shown to converge to the global optimum with a complexity of $\tilde{\mathcal O}(1/\epsilon)$ in terms of the optimality gap and the constraint violation, which improves the complexity of the existing primal-dual approach by a factor of $\mathcal O(1/\epsilon)$ \citep{ding2020natural, paternain2019constrained}.
PER-ETD: A Polynomially Efficient Emphatic Temporal Difference Learning Method
Although ETD has been shown to converge asymptotically to a desirable value function, it is well-known that ETD often encounters a large variance so that its sample complexity can increase exponentially fast with the number of iterations.
A Unified Off-Policy Evaluation Approach for General Value Function
We further show that unlike GTD, the learned GVFs by GenTD are guaranteed to converge to the ground truth GVFs as long as the function approximation power is sufficiently large.
Doubly Robust Off-Policy Actor-Critic: Convergence and Optimality
We also show that the overall convergence of DR-Off-PAC is doubly robust to the approximation errors that depend only on the expressive power of approximation functions.
Proximal Gradient Descent-Ascent: Variable Convergence under KŁ Geometry
By leveraging this Lyapunov function and the K{\L} geometry that parameterizes the local geometries of general nonconvex functions, we formally establish the variable convergence of proximal-GDA to a critical point $x^*$, i. e., $x_t\to x^*, y_t\to y^*(x^*)$.
CRPO: A New Approach for Safe Reinforcement Learning with Convergence Guarantee
To demonstrate the theoretical performance of CRPO, we adopt natural policy gradient (NPG) for each policy update step and show that CRPO achieves an $\mathcal{O}(1/\sqrt{T})$ convergence rate to the global optimal policy in the constrained policy set and an $\mathcal{O}(1/\sqrt{T})$ error bound on constraint satisfaction.
Sample Complexity Bounds for Two Timescale Value-based Reinforcement Learning Algorithms
For linear TDC, we provide a novel non-asymptotic analysis and show that it attains an $\epsilon$-accurate solution with the optimal sample complexity of $\mathcal{O}(\epsilon^{-1}\log(1/\epsilon))$ under a constant stepsize.
Enhanced First and Zeroth Order Variance Reduced Algorithms for Min-Max Optimization
Specifically, a novel variance reduction algorithm SREDA was proposed recently by (Luo et al. 2020) to solve such a problem, and was shown to achieve the optimal complexity dependence on the required accuracy level $\epsilon$.
A Primal Approach to Constrained Policy Optimization: Global Optimality and Finite-Time Analysis
To demonstrate the theoretical performance of CRPO, we adopt natural policy gradient (NPG) for each policy update step and show that CRPO achieves an $\mathcal{O}(1/\sqrt{T})$ convergence rate to the global optimal policy in the constrained policy set and an $\mathcal{O}(1/\sqrt{T})$ error bound on constraint satisfaction.
When Will Generative Adversarial Imitation Learning Algorithms Attain Global Convergence
Generative adversarial imitation learning (GAIL) is a popular inverse reinforcement learning approach for jointly optimizing policy and reward from expert trajectories.
Gradient Free Minimax Optimization: Variance Reduction and Faster Convergence
In this paper, we focus on such a gradient-free setting, and consider the nonconvex-strongly-concave minimax stochastic optimization problem.
Non-asymptotic Convergence Analysis of Two Time-scale (Natural) Actor-Critic Algorithms
In the first nested-loop design, actor's one update of policy is followed by an entire loop of critic's updates of the value function, and the finite-sample analysis of such AC and NAC algorithms have been recently well established.
Improving Sample Complexity Bounds for (Natural) Actor-Critic Algorithms
We show that the overall sample complexity for a mini-batch AC to attain an $\epsilon$-accurate stationary point improves the best known sample complexity of AC by an order of $\mathcal{O}(\epsilon^{-1}\log(1/\epsilon))$, and the overall sample complexity for a mini-batch NAC to attain an $\epsilon$-accurate globally optimal point improves the existing sample complexity of NAC by an order of $\mathcal{O}(\epsilon^{-1}/\log(1/\epsilon))$.
Non-asymptotic Convergence of Adam-type Reinforcement Learning Algorithms under Markovian Sampling
Despite the wide applications of Adam in reinforcement learning (RL), the theoretical convergence of Adam-type RL algorithms has not been established.
Reanalysis of Variance Reduced Temporal Difference Learning
Furthermore, the variance error (for both i. i. d.\ and Markovian sampling) and the bias error (for Markovian sampling) of VRTD are significantly reduced by the batch size of variance reduction in comparison to those of vanilla TD.
Two Time-scale Off-Policy TD Learning: Non-asymptotic Analysis over Markovian Samples
Gradient-based temporal difference (GTD) algorithms are widely used in off-policy learning scenarios.
Finite-Sample Analysis for SARSA with Linear Function Approximation
For this fitted SARSA algorithm, we also provide its finite-sample analysis.
When Will Gradient Methods Converge to Max-margin Classifier under ReLU Models?
We study the implicit bias of gradient descent methods in solving a binary classification problem over a linearly separable dataset.
