Kernel dimension reduction in regression

We present a new methodology for sufficient dimension reduction (SDR). Our methodology derives directly from the formulation of SDR in terms of the conditional independence of the covariate $X$ from the response $Y$, given the projection of $X$ on the central subspace [cf. J. Amer. Statist. Assoc. 86 (1991) 316--342 and Regression Graphics (1998) Wiley]. We show that this conditional independence assertion can be characterized in terms of conditional covariance operators on reproducing kernel Hilbert spaces and we show how this characterization leads to an $M$-estimator for the central subspace. The resulting estimator is shown to be consistent under weak conditions; in particular, we do not have to impose linearity or ellipticity conditions of the kinds that are generally invoked for SDR methods. We also present empirical results showing that the new methodology is competitive in practice.Comment: Published in at http://dx.doi.org/10.1214/08-AOS637 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

A salary schedule for Lawrence, Mass

Thesis (M.A.)--Boston University, 1946. This item was digitized by the Internet Archive

Mercury Contamination in Benthic Biota and Sediments within the New York Bight Wind Energy Area

Aquatic ecosystems are showing increasing evidence of contamination by persistent, toxic substances, including metals such as mercury. Mercury (Hg) is truly an unusual element, having no essential biological function. Its unique physical properties have been utilized for various industrial and commercial purposes. This has led to serious exposure to this known neurotoxin. Additionally, the deposition and effluents of mercury in air, water, and soil have impacted food chain dynamics. The potential of bioaccumulation and biomagnification of Hg within aquatic ecosystems can have serious negative implication on ecosystem functions and services. Furthermore, understanding the difference between those pathways can provide a fundamental role in heavy metal cycling within aquatic food webs. The primary objective of this research was to establish a baseline for mercury contamination of benthic biota and sediments in the New York Wind Energy Area (NYWEA), which could be useful to the US Department of Energy for their site assessment and planning and installation of wind farms within the NYWEA. Analysis of sediment samples from 18 sampling sites was conducted to measure total Hg concentration. Station 41 (14.08 g/kg) and Station B73 (5.51 g/kg) exhibited the highest total mean Hg concentration whereas Station 27 (1.883 g/kg), Station 21 (1.821 g/kg), and Station 33 (1.7496 g/kg) exhibited the lowest total mean Hg concentration. Analysis of biota from 19 sampling sites within the NYWEA was conducted to assess total Hg concentration. The long-clawed hermit crab (Pagurus longicarpus), sand shrimp (Crangon septemspinosa), gulf stream flounder (Citharichthys arctifrons), dog whelk (Citharichthys arctifrons), and rock crab (Cancer irroratus) all exhibited significant differences in mean total Hg concentration among sampling sites. While diversity and species richness are considered good indicators of stress of contaminated systems, Hg contaminant loads observed here did not seem to influence community structure or individual species. The results of this study show that Hg contamination in both sediments and biota is present at low levels in the NYWEA, but below US Environmental Protection Agency limits. This suggests that limited Hg contamination in this region is a positive evaluation for the region and food webs in the New York Bight

Progress in compilation of the 1:2,000,000-scale topographic map

The application of special photogrammetric techniques has enabled the systematic mapping of Mars' topography at a scale of 1:2,000,000, using high-altitude Viking Orbiter pictures. In fiscal 86, compilation was completed of the 24 subquadrangles that make up the quadrangles MC-12, MC-13, MC-14, MC-15, MC-20, and MC-21. This work completes compilation of the 60 topographic maps covering the equatorial belt (lat. + or - 30 deg). The remaining 80 subquadrangles of Mars are planned to be completed within 3 years (27, 27 and 26 subquadrangles, in fiscal 87, 88, and 89, respectively). Elevations on all topographic maps are relative to the Mars topographic datum. The maps have a contour interval of 1 km and a precision of + or - 1 km. The equatorial-belt maps are Mercator projections having true scale at lat. + or - 27.476 deg. These maps provide more precise information than do those previously available and they will help in understanding the geologic processes that have shaped the Martian surface

A case of bovine raw milk contamination with Listeria monocytogenes

peer-reviewedDuring routine sampling of bulk raw milk on a dairy farm, the pathogenic bacteria Listeria monocytogenes was found to be a contaminant, at numbers < 100 cfu/ml. A strain with an indistinguishable pulsed-field gel electrophoresis pattern was isolated from the bulk milk two months later. Environmental swabs taken at the dairy environment were negative for the presence of L. monocytogenes, indicating a possible case of excretion of the L. monocytogenes directly into the milk. Milk samples were collected from the individual cows and analysed, resulting in the identification of L. monocytogenes excretion (at 280 cfu/ml) from one of the 4 mammary quarters of one dairy cow out of 180. When the infected cow was isolated from the herd, no L. monocytogenes was detected from the remaining herd. The pulsed-field gel electrophoresis pattern of the strain from the individual cow was indistinguishable from that originally isolated from the bulk milk. The infected cow did not show any clinical signs of disease, nor did the appearance of the milk have any physical abnormalities. Antibiotic treatment of the infected mammary quarter was found to be ineffective. This study shows that there can be risks associated with direct contamination of raw milk with L. monocytogenes.Teagasc Walsh Fellowship; Irish Department of Agriculture, Fisheries and Food, Food Institutional Research Measure (Irish Microbial Risk Assessment Network project); European Union (EU), 6th Framework Programme (BIOTRACER project)

Compatible relations on filters and stability of local topological properties under supremum and product

An abstract scheme using particular types of relations on filters leads to general unifying results on stability under supremum and product of local topological properties. We present applications for Frechetness, strong Frechetness, countable tightness and countable fan-tightness, some of which recover or refine classical results, some of which are new. The reader may find other applications as well.Comment: 28 page

Closing the Gap Refresh: papering over the gaps or structural reform?

Ten years on from the Council of Australian Governments committing to National Indigenous Reform Agreement – Closing the Gap, the Federal Government has announced the Closing the Gap Refresh. Five academics and visitors at the Centre for Aboriginal Economic Policy Research made submissions as part of the Closing the Gap Refresh ‘Have Your Say’ process, engaging with the Closing the Gap Refresh from specialist disciplinary perspectives and with their grounded expertise. The views of these individuals have been consolidated into a single document to ensure their longer-term availability. Together, the submissions in this CAEPR Topical Issue paper argue that the failure of gaps to close is a reflection of a failed policy-making process. All five papers indicate the need for substantial change and structural reform, and express concern at the risk that the current ‘refresh’ will simply ‘paper over the gaps’. They identify a need for governments to do policy differently, and suggest avenues toward a reform of the policy-making process in Indigenous Affairs

Design of an Orthopedic Device to Prevent Lumbosacral Stenosis in Military Working Dogs

The goal of this study was to design a safe, easily implanted, and easily manufactured orthopedic device to alleviate spinal cord pressure in the lumbosacral facet joint of military working dogs. A literature review showed the joint loading to be 200N, and displacement was measured to be 2mm during a cadaver dissection. The device is made up of three parts, a central spring micro-welded to two endplates. The plates are designed for implantation after the L7 and S1 spinuous processes have been removed. Testing of the commercial spring showed displacement capacity over 5mm and loads of up to 625N. Mechanical testing of the device withstood loads of 225N and displacements of 5mm. Thus, the device provides a means of alleviating stress in the lumbosacral joint while preserving range of motion