Neural Embeddings of Graphs in Hyperbolic Space

Neural embeddings have been used with great success in Natural Language Processing (NLP). They provide compact representations that encapsulate word similarity and attain state-of-the-art performance in a range of linguistic tasks. The success of neural embeddings has prompted significant amounts of research into applications in domains other than language. One such domain is graph-structured data, where embeddings of vertices can be learned that encapsulate vertex similarity and improve performance on tasks including edge prediction and vertex labelling. For both NLP and graph based tasks, embeddings have been learned in high-dimensional Euclidean spaces. However, recent work has shown that the appropriate isometric space for embedding complex networks is not the flat Euclidean space, but negatively curved, hyperbolic space. We present a new concept that exploits these recent insights and propose learning neural embeddings of graphs in hyperbolic space. We provide experimental evidence that embedding graphs in their natural geometry significantly improves performance on downstream tasks for several real-world public datasets.Comment: 7 pages, 5 figure

Justice and the Tendency towards Good: The Role of Custom in Hume's Theory of Moral Motivation

In the Book of his Treatise devoted to morality, Hume gives more consideration to what he calls "artificial virtues" than to natural virtues.1 Artificial virtues rely on conventions which have arisen for non-moral reasons, but which come to be understood as beneficial to society so that, as a consequence, we come to see adherence to these conventions as being morally obligatory. The main such virtue which Hume discusses is "justice," by which he means primarily a respect for the conventions concerning property rights and property transfer, such as the convention to pay back loans of money. Despite Hume's attention on justice, there is much that is puzzling about his..

Farming the forests of Appalachia : opportunities and challenges

Paper presented at the 11th North American Agroforesty Conference, which was held May 31-June 3, 2009 in Columbia, Missouri.In Gold, M.A. and M.M. Hall, eds. Agroforestry Comes of Age: Putting Science into Practice. Proceedings, 11th North American Agroforestry Conference, Columbia, Mo., May 31-June 3, 2009.People have been informally farming their forests for generations, although only in recent years has attention been directed at formalizing this land-use practice through research and development. Forest farming is becoming popular for landowners to diversify income, improve resource management, and increase biological diversity. The social, ecological and economic implications of forest farming may be significant to private landowners. Forest farming focuses on producing herbaceous plants that traditionally have been wild-harvested for food, medicine, and other income generating opportunities. Many opportunities and challenges face landowners interested in forest farming. Many markets for forest farmed products are developing rapidly. Under-utilized species may present specialty opportunities for creative entrepreneurs. Shifting from wild-harvest to cultivation may present significant challenges to rural people who are economically marginalized. These new forest ventures may require additional skills and expertise. There may be additional capital or labor requirements that could put undue burden on interested landowners. Market demand and economies of scale may reduce the attractiveness of alternative forest enterprises. Technical challenges of cultivating native herbaceous plants under forest canopies may be daunting, as well. Opportunities and challenges abound for developing forest farming into a viable land-use practice for landowners in the Appalachian hardwood region.James Chamberlain ; National Agroforestry Center, Southern Research Station, USDA Forest Service 1650 Ramble Road, Blacksburg, VA 24060.Includes bibliographical references

Justice and the tendency towards good: the role of custom in Hume's theory of moral motivation

Given the importance of sympathetic pleasures within Hume's account of approval and moral motivation, why does Hume think we feel obliged to act justly on those occasions when we know that doing so will benefit nobody? I argue that Hume uses the case of justice as evidence for a key claim regarding all virtues. Hume does not think we approve of token virtuous actions, whether natural or artificial, because they cause or aim to cause happiness in others. It is sufficient for the action to be of a type which has "a tendency to the public good" for us to feel approval of it, and to be motivated to perform it. Once we are aware that just actions tend to cause happiness, we approve of all just actions, even token actions which cause more unhappiness than happiness

History that Slithers: Kra-Dai and the Pythonidae

This paper brings together a number of disciplines in order to demonstrate how historical, anthropological, ecological, zoogeographical, ethnobiological, and linguistic evidence relating to the physical distribution and linguistic representations of pythons in northern Southeast Asia and southern China can be brought to bear on Kra-Dai prehistory and intrafamilial as well as interethnic relationships. The normal and most recognized word for 'python' is confined to the Tai family proper, and even then there are some qualifications. Two species of python are found in much of the Tai linguistic area south of the Sino-Vietnamese border, but only one, the Burmese python, occurs in Guangxi, Guangdong, and Hainan. Some Central Tai dialects have acquired another name that seems to be Austroasiatic (AA) in origin, and yet no AA languages are found in those areas. It is suggested that these dialects received the word via Kra to the west. On the eastern side, yet another surprising correspondence is noted between Lung Ming in southern Guangxi and Hlai on Hainan. Sek, located far to the south, which usually preserves archaic forms of Be-Tai, has no words for 'python' that correspond to those in the rest of the family. Close examination of the linguistics of this particular member of the Southeast Asian mega-fauna reveals a pattern of interaction between the families of the Kra-Dai stock, Austroasiatic, and southern Chinese that mirrors the phylogenetic tree