North American Species of the Genus Hydrochoreutes (Acarina: Pionidae)

Excerpt: Members of the water mite genus Hydrochoreutes have a Holarctic distribution. They are found in lakes, ponds, and sluggish streams, but usually only in small numbers and therefore long series of specimens are difficult to obtain. Two species, ungulatus (Koch) and krameri Piersig, have a widespread range in Europe and Siberia and the latter species is also known from Algeria. Marshall (1937) reported ungulatus from Maine, Michigan, Wisconsin and California. However, the present author has seen no specimens from North America which can be assigned to the latter species and the illustrations in Marshall\u27s paper are definitely not those of ungulatus. Therefore. there are no authentic records of the latter species in the New World. Cook (1956) named a new species, intermedius, from North America. Both the description and illustrations are inadequate for the latter and it is treated along with four new species in this paper

Investigation into the combination of complementary MOS and complementary bipolar circuits on a monolithic silicon chip Final report

Combination of complementary MOS and complementary bipolar circuits on monolithic silicon chi

THE FEDERAL ROLE IN SMALL AREA PLANNING

Public Economics,

Determining the dimension of iterative Hessian transformation

The central mean subspace (CMS) and iterative Hessian transformation (IHT) have been introduced recently for dimension reduction when the conditional mean is of interest. Suppose that X is a vector-valued predictor and Y is a scalar response. The basic problem is to find a lower-dimensional predictor \eta^TX such that E(Y|X)=E(Y|\eta^TX). The CMS defines the inferential object for this problem and IHT provides an estimating procedure. Compared with other methods, IHT requires fewer assumptions and has been shown to perform well when the additional assumptions required by those methods fail. In this paper we give an asymptotic analysis of IHT and provide stepwise asymptotic hypothesis tests to determine the dimension of the CMS, as estimated by IHT. Here, the original IHT method has been modified to be invariant under location and scale transformations. To provide empirical support for our asymptotic results, we will present a series of simulation studies. These agree well with the theory. The method is applied to analyze an ozone data set.Comment: Published at http://dx.doi.org/10.1214/009053604000000661 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Principal Fitted Components for Dimension Reduction in Regression

We provide a remedy for two concerns that have dogged the use of principal components in regression: (i) principal components are computed from the predictors alone and do not make apparent use of the response, and (ii) principal components are not invariant or equivariant under full rank linear transformation of the predictors. The development begins with principal fitted components [Cook, R. D. (2007). Fisher lecture: Dimension reduction in regression (with discussion). Statist. Sci. 22 1--26] and uses normal models for the inverse regression of the predictors on the response to gain reductive information for the forward regression of interest. This approach includes methodology for testing hypotheses about the number of components and about conditional independencies among the predictors.Comment: Published in at http://dx.doi.org/10.1214/08-STS275 the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

Matrix-Variate Regressions and Envelope Models

Modern technology often generates data with complex structures in which both response and explanatory variables are matrix-valued. Existing methods in the literature are able to tackle matrix-valued predictors but are rather limited for matrix-valued responses. In this article, we study matrix-variate regressions for such data, where the response Y on each experimental unit is a random matrix and the predictor X can be either a scalar, a vector, or a matrix, treated as non-stochastic in terms of the conditional distribution Y|X. We propose models for matrix-variate regressions and then develop envelope extensions of these models. Under the envelope framework, redundant variation can be eliminated in estimation and the number of parameters can be notably reduced when the matrix-variate dimension is large, possibly resulting in significant gains in efficiency. The proposed methods are applicable to high dimensional settings.Comment: 28 pages, 4 figure

Loneliness and life satisfaction amongst three cultural groups

Abstract Studies into loneliness and life satisfaction have rarely assessed the role of culture in moderating the relationship between these variables. The present study examined the relationship between loneliness and life satisfaction using data from three nonstudent samples collected from Italian, Anglo-Canadian and Chinese-Canadian populations. A total of 206 respondents completed the Revised UCLA Loneliness Scale (Russell, Peplau, & Cutrona, 1980) and the Satisfaction with Life Scale (Diener, Emmons, Larsen, & Griffin, 1985). Two contrasting hypotheses were compared: one, a “postmodern” hypothesis, predicting that the relationship between life satisfaction and loneliness would be stronger in our individualist sample of Anglo-Canadians, and a second, “relational” hypothesis predicting this association to be strongest in our collectivist, Chinese-Canadian sample. Our findings demonstrated that culture has a small but significant impact on the relationship between loneliness and life satisfaction, and, consistent with the relational hypothesis, the relationship between the two concepts was strongest among our Chinese-Canadian respondents and weakest among our Anglo-Canadian participants This finding is discussed in the context of the strong expectations of social cohesion in collectivist societies

A bioregional classification of the continental shelf of northeastern North America for conservation analysis and planning based on representation

Understanding how well National Marine Sanctuaries and other marine protected areas represent the diversity of species present within and among the biogeographic regions where they occur is essential for assessing their conservation value and identifying gaps in the protection of biological diversity. One of the first steps in any such assessment should be the development of clearly defined and scientifically justified planning boundaries representing distinct oceanographic conditions and faunal assemblages. Here, we propose a set of boundaries for the continental shelf of northeastern North America defined by subdivisions of the Eastern Temperate Province, based on a review and synthesis (i.e. meta-analysis) of the scientific literature. According to this review, the Eastern Temperate Province is generally divided into the Acadian and Virginian Subprovinces. Broad agreement places the Scotian Shelf, Gulf of Maine, and Bay of Fundy within the Acadian Subprovince. The proper association of Georges Bank is less clear; some investigators consider it part of the Acadian and others part of the Virginian. Disparate perspectives emerge from the analysis of different groups of organisms. Further, while some studies suggest a distinction between the Southern New England shelf and the rest of the Mid-Atlantic Bight, others describe the region as a broad transition zone with no unique characteristics of its own. We suggest there exists sufficient evidence to consider the Scotian Shelf, Gulf of Maine, Georges Bank, Southern New England, and Southern Mid-Atlantic Bight as distinct biogeographic regions from a conservation planning perspective, and present a set of proposed mapped boundaries. (PDF contains 23 pages.