Crawling in Rogue's Dungeons With Deep Reinforcement Techniques

This article is a report of our extensive experimentation, during the last two years,of deep reinforcement techniques for training an agent to move in the dungeons of the famous Rogue video-game. The challenging nature of the problem is tightly related the procedural, random generation of new dungeon maps at each level, that forbids any form of level-specific learning, and forces to address the navigation problem in its full generality. Other interesting aspects of the game from the point of view of automatic learning are the partially observable nature of the problem, since maps are initially not visible and get discovered during exploration, and the problem of sparse rewards, requiring the acquisition of complex, non-reactive behaviors involving memory and planning. In this article, we develop on previous works to make a more systematic comparison of different learning techniques, focusing in particular on Asynchronous Advantage Actor-Critic (A3C) and Actor-Critic with Experience Replay (ACER). In a game like Rogue, sparsity of rewards is mitigated by the variability of the dungeon configurations (sometimes, by luck, exit is at hand); if this variability can be tamed - as ACER, better than other algorithms, seems able to do - the problem of sparse rewards can be overcome without any need of intrinsic motivations

Caught between Worlds: British Captivity Narratives in Fact and Fiction

The captivity narrative has always been a literary genre associated with America. Joe Snader argues, however, that captivity narratives emerged much earlier in Britain, coinciding with European colonial expansion, the development of anthropology, and the rise of liberal political thought. Stories of Europeans held captive in the Middle East, America, Africa, and Southeast Asia appeared in the British press from the late sixteenth through the late eighteenth centuries, and captivity narratives were frequently featured during the early development of the novel. Until the mid-eighteenth century, British examples of the genre outpaced their American cousins in length, frequency of publication, attention to anthropological detail, and subjective complexity. Using both new and canonical texts, Snader shows that foreign captivity was a favorite topic in eighteenth-century Britain. An adaptable and expansive genre, these narratives used set plots and stereotypes originating in Mediterranean power struggles and relocated in a variety of settings, particularly eastern lands. The narratives’ rhetorical strategies and cultural assumptions often grew out of centuries of religious strife and coincided with Europe’s early modern military ascendancy. Caught Between Worlds presents a broad, rich, and flexible definition of the captivity narrative, placing the American strain in its proper place within the tradition as a whole. Snader, having assembled the first bibliography of British captivity narratives, analyzes both factual texts and a large body of fictional works, revealing the ways they helped define British identity and challenged Britons to rethink the place of their nation in the larger world. Winner of the 2001 MLA Independent Scholars Prize A Choice Outstanding Academic Title Will be valuable for years to come to scholars working on life writing, colonial and post-colonial studies, and the history of transatlantic Anglophone literature. —Biography Should be valuable for years to come to scholars working on life-writing, travel writing, colonial and post-colonial studies, and the history of transatlantic Anglophone literature. —Biography: An Interdisciplinary Quarterly Shows that foreign captivity was a favorite topic in 18th-century Britain, and reveals that these narratives’ rhetorical strategies and cultural assumptions often grew out of centuries of religious strife and coincided with Europe’s early-modern military ascendancy. —Book News His thought-provoking book will make a real contribution to the discussions of the captivity genre. —Choice Seeks to place American captivity stories into a much broader context—that of an established culture getting knocked into a new perspective by contact with utter strangeness. —East-Central Intelligencer Extremely well written. . . . Can truly claim to have brought the genre to light and to life. —Eighteenth-Century Fiction Snader makes a persuasive case that scholarship on American captivity narratives has suffered from a kind of tunnel-vision in looking too exclusively at material relating to North America. —Paul K. Alkon A fine companion to studies of Utopias, of American captivity narratives, of travel literature, and of eighteenth-century fiction in general. . . . Pleasingly well-written and organized. —Percy G. Adams A book about captivity narratives . . . showing that they are a genre with a much longer history than is commonly assumed by those who refer only to North American examples. —SEL (Studies in English Literature) A pioneering work in early-modern British and American studies. . . . The first extended study of the transatlantic relationship between the popular genres of the captivity narrative and the novel. —Vincent Carretthttps://uknowledge.uky.edu/upk_english_language_and_literature_british_isles/1016/thumbnail.jp