Alternative strategies for decision list construction

This work surveys well-known approaches to building decision lists. Some novel variations to strategies based on default rules for the most common class and insertion of new rules before the default rule are presented. These are expected to offer speed up in the construction of the decision list as well as compression of the length of the list. These strategies and a testing regime have been implemented and some empirical studies done to compare the strategies. Experimental results are presented and interpreted. We show that all strategies deliver decision lists of comparable accuracy. However, two techniques are shown to deliver this accuracy with lists composed of significantly fewer rules than alternative strategies. Of these, one also demonstrates significant computational advantages. The prepending strategy is also demonstrated to produce decision lists which are as much as an order of magnitude shorter than those produced by CN2.

From crystals to pixels: new technology in the documentary work of John Hughes

Film technology, in the broadest sense, embraces a vast array of knowledge, skills, tools, and systems. These include the codes and conventions of screen representation at the centre of much screen scholarship. The electro-mechanical tools of filmmaking are less often the focus of academic study than these codes and conventions, but they are central to them and to the daily work of artists and educators in the field of screen production. This paper traces the scope and significance of technical change, for independent film making, over the past four decades. Melbourne documentary filmmaker John Hughes provides a varied and expansive oeuvre through which to arrange an historical equipment list.

Limiting the list : human rights and intangible cultural heritage

UNESCO's Convention for the Safeguarding of Intangible Heritage came into force in April 2006, signalling a major expansion of the global system of heritage protection from the tangible to the intangible. It is an expansion that some heritage professionals see as opening up a Pandora's box of confusions and complexities. The conservation of inanimate objects tangible sites and monuments and artefacts - is difficult enough; but the protection of heritage embodied in people raises new sets of ethical and practical issues. The paper canvasses these concerns and focuses on how the notion of human rights must be used as a way of limiting and shaping the Intangible List. In particular it outlines the ways in which the protection and preservation of cultural heritage is linked to 'cultural rights' as a form of human rights. This linkage is not clearly recognised by cultural heritage practitioners in many countries, who view their work merely as technical, or even by human rights workers, despite the abundance of opportunities around the world to witness people struggling to assert their cultural rights in order to protect their heritage and identity.

Establishing IUCN red list criteria for threatened ecosystems

The potential for conservation of individual species has been greatly advanced by the International Union for Conservation of Nature's (IUCN) development of objective, repeatable, and transparent criteria for assessing extinction risk that explicitly separate risk assessment from priority setting. At the IV World Conservation Congress in 2008, the process began to develop and implement comparable global standards for ecosystems. A working group established by the IUCN has begun formulating a system of quantitative categories and criteria, analogous to those used for species, for assigning levels of threat to ecosystems at local, regional, and global levels. A final system will require definitions of ecosystems; quantification of ecosystem status; identification of the stages of degradation and loss of ecosystems; proxy measures of risk (criteria); classification thresholds for these criteria; and standardized methods for performing assessments. The system will need to reflect the degree and rate of change in an ecosystem's extent, composition, structure, and function, and have its conceptual roots in ecological theory and empirical research. On the basis of these requirements and the hypothesis that ecosystem risk is a function of the risk of its component species, we propose a set of four criteria: recent declines in distribution or ecological function, historical total loss in distribution or ecological function, small distribution combined with decline, or very small distribution. Most work has focused on terrestrial ecosystems, but comparable thresholds and criteria for freshwater and marine ecosystems are also needed. These are the first steps in an international consultation process that will lead to a unified proposal to be presented at the next World Conservation Congress in 2012.