You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Reinforcement learning in robotics: A survey 
Chapter Title:  Non-parametric policies 
1. Abstract of Cited Paper (BIB001):  Policy search is a successful approach to reinforcement learning. However, policy improvements often result in the loss of information. Hence, it has been marred by premature convergence and implausible solutions. As first suggested in the context of covariant policy gradients (Bagnell and Schneider 2003), many of these problems may be addressed by constraining the information loss. In this paper, we continue this path of reasoning and suggest the Relative Entropy Policy Search (REPS) method. The resulting method differs significantly from previous policy gradient approaches and yields an exact update step. It works well on typical reinforcement learning benchmark problems.

Literature Review:
Polices based on nonparametric regression approaches often allow a more datadriven learning process. This approach is often preferable over the purely parametric policies listed above because the policy structure can evolve during the learning process. Such approaches are especially useful when a policy learned to adjust the existing behaviors of a lower-level controller, such as when choosing among different robothuman interaction possibilities BIB001 , selecting among different striking movements in a table tennis task BIB002 , and setting the meta-actions for dart throwing and table tennis hitting tasks .