Improving Statistical Language Model Performance with Automatically Generated Word Hierarchies

An automatic word classification system has been designed which processes word unigram and bigram frequency statistics extracted from a corpus of natural language utterances. The system implements a binary top-down form of word clustering which employs an average class mutual information metric. Resulting classifications are hierarchical, allowing variable class granularity. Words are represented as structural tags --- unique $n$-bit numbers the most significant bit-patterns of which incorporate class information. Access to a structural tag immediately provides access to all classification levels for the corresponding word. The classification system has successfully revealed some of the structure of English, from the phonemic to the semantic level. The system has been compared --- directly and indirectly --- with other recent word classification systems. Class based interpolated language models have been constructed to exploit the extra information supplied by the classifications and some experiments have shown that the new models improve model performance.Comment: 17 Page Paper. Self-extracting PostScript Fil

Physical and Chemical Controls on Habitats for Life in the Deep Subsurface Beneath Continents and Ice

S.M. was funded by an STFC Aurora studentship (grant ST/1506102/1) and the NASA Astrobiology Institute Program on Foundations of Complex Life, Evolution, Preservation and Detection on Earth and Beyond (grant NNA13AA90A). J.P. was supported by NERC grant NE/G00322X/l.Peer reviewedPublisher PD

Sampling methane in basalt on Earth and Mars

Peer reviewedPublisher PD

Evidence for Seismogenic Hydrogen Gas, a Potential Microbial Energy Source on Earth and Mars

M thanks the STFC for a PhD studentship and the NASA Astrobiology Institute for additional funding (NNAI13AA90A; Foundations of Complex Life, Evolution, Preservation and Detection on Earth and Beyond). Alison Wright, Roger Gibson and Edward Lynch are thanked for contributing samples. We thank three anonymous reviewers for their insightful comments.Peer reviewedPostprin

Circumstellar habitable zones for deep terrestrial biospheres

SM and JOJ are grateful to the UK Science and Technology Facilities Council (STFC) for Aurora Studentships. We thank Dr. Stephen Clifford (LPI), Dr. Ravi Kopparapu (Penn State), and Claire Davis (St. Andrews) for generous technical advice. We thank Norm Sleep and two anonymous reviewers for constructive reviews of the manuscriptPeer reviewedPostprin

A review and analysis of the management of retention at an institute of further and higher education in Northern Ireland

This research is a case study concerning retention in Further and Higher Education (FHE) generally and an Institute of Further and Higher Education in particular. This college will be fictitiously referred to as Lough Neagh Institute (LNIFHE). Retention is becoming increasingly important in education as it affects achievement with implications for any value added which could be gained and the overall provision of quality given to the learner. Poor retention generally results in a depleted range of skills acquired by the student. A policy on the management of retention has not yet been formally constructed, despite overall retention within LNIFHE developing a distinctive downward trend in some courses. Initially a review of the literature indicated that the most pertinent areas to investigate in the management of retention were; - factors involved in early withdrawal, - support and guidance processes, - quality systems as well as, - strategies that were employed to optimise retention at LNIFHE. The four aims of the study were built around these areas. To test opinion on some of these themes a sample of the three stakeholders most directly involved, the staff, students and senior management at LNIFHE during the years 2004-2005 was surveyed and collated. The methodology involved the techniques of questionnaires, semi-structured and open-ended interviews, contemporaneous comments recorded in the diary and desk analysis. The investigation also studied the strategy employed to optimise retention by management at LNIFHE by examining some retention related policies from within the College Development Plan. The school improvement model of Creemers was analysed and found to be a useful tool, which could be adapted for use in LNIFHE. A variant of the model was proposed in the final chapter. Retention research so far has been of an a-theoretical nature and generally does not account for the cumulative and interrelating effects of the external and internal factors which are known to be influential on students. The most important dimension which emerged in this study was the importance of motivation for students and how this is positively influence by better support provision. Within LNIFHE, there are differences in the perspectives of the three main stakeholders notably in the area of quality provision and partially as a result of this, implementation gaps between policy and practice exist with consequent negative implications for student retention. There is no procedure in LNIFHE for the identification of students who are at risk of withdrawing. Some structural and organisational changes such as the construction of a retention policy the creation of the post of retention manager along with recommendation for improved monitoring, support and the maintenance of quality at all levels were suggested. It was proposed that better communication between the 3 stakeholders at LNIFHE will improve motivation of staff and students which will have a beneficial effect on retention

LOCAL GOVERNMENT Community Greenspace Preservation: Create the Georgia Greenspace Commission: Establish the Georgia Greenspace Trust Fund

By adding several sections to the Georgia Code relating to local government, the Act creates the Georgia Greenspace Commission and provides for its membership, powers and duties, and operations. The Act provides a flexible framework of policies, rules, and regulations through which Georgia\u27s populous and rapidly growing cities and counties can voluntarily develop programs to preserve community green space for recreational activities and protection of natural resources. The Act also creates the Georgia Greenspace Trust Fund, provides guidelines for appropriations and contributions to the fund, and defines how grants will be disbursed to local governments for preservation of greenspace