We propose and analyze a class of actor-critic algorithms for simulation-based optimization of a Markov decision process over a parameterized family of randomized stationary policies. These are two-time-scale algorithms in which the critic uses TD learning with a linear approximation architecture and the actor is updated in an approximate gradient direction based on information provided by the ...

This paper investigates a novel model-free reinforcement learning architecture, the Natural Actor-Critic. The actor updates are based on stochastic policy gradients employing Amari’s natural gradient approach, while the critic obtains both the natural policy gradient and additional parameters of a value function simultaneously by linear regression. We show that actor improvements with natural p...

this article discusses the stylistic criticism of the adonis’s poetry, based on the book modern poetic style by salah fadel. for this purpose, this article focuses on the critic himself and investigates the basic issues that he raised, specifies the concept and the expressions that he conceptualized, and the methodological techniques that he employed. this researcher believes that the critic ha...

4 Actor-Critic Marble Control 4 4.1 R-code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.2 The critic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.3 Unstable actors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.4 Trading off stability against...

Ann Jurecic is assistant professor in the Department of English at Rutgers University, New Brunswick, where she teaches courses in writing as well as literature and medicine. Her book Illness as Narrative is forthcoming from University of Pittsburgh Press. Her work has appeared in the journals Literature and Medicine, Pedagogy, and Biography as well as in College English, and she serves as book...

We describe an agent based artist-critic simulation. Artist agents use a swarm based evolutionary art system to evolve images that try to match their preferences. Preferred images are submitted to critic agents who then decide, accordingly to their own criteria, which images should be displayed in a public gallery. The purpose of our model is to enable the implementation of a variety of behavio...

Inductive theorem provers often diverge. This paper describes a simple critic, a computer program which monitors the construction of inductive proofs attempting to identify diverging proof attempts. Divergence is recognized by means of a \diierence matching" procedure. The critic then proposes lemmas and generalizations which \ripple" these differences away so that the proof can go through with...

A dual neural network ‘adaptive critic approach’ is used in this study to generate midcourse guidance commands for a missile to reach a predicted impact point while maximizing its final velocity. The adaptive critic approach is based on approximate dynamic programming. The first network, called a ‘critic’, network, outputs the Lagrangian multipliers arising in an optimal control formulation whi...