Prenatal Development of Interlimb Motor Learning in the Rat Fetus

The role of sensory feedback in the early ontogeny of motor coordination remains a topic of speculation and debate. On E20 of gestation (the 20th day after conception, 2 days before birth), rat fetuses can alter interlimb coordination after a period of training with an interlimb yoke, which constrains limb movement and promotes synchronized, conjugate movement of the yoked limbs. The aim of this study was to determine how the ability to express this form of motor learning may change during prenatal development. Fetal rats were prepared for in vivo study at 4 ages (E18–21) and tested in a 65‐min training‐and‐testing session examining hind limb motor learning. A significant increase in conjugate hind limb activity was expressed by El9, but not El 8 fetuses, with further increases in conjugate hind limb activity on E20 and E21. These findings suggest substantial development of the ability of fetal rats to modify patterns of interlimb coordination in response to kinesthetic feedback during motor training before birth.     

Immigrant Settlement Patterns: The Role of Metropolitan Characteristics*

Immigration continues to change the social, economic, and political landscapes of urban America. Consequently, scholars, as well as the general public, are interested in the internal migration patterns of immigrants. In this research, we identify and explain the characteristics of metropolitan areas that have the strongest effects on the percentage change in the foreign‐born population between 1990 and 2000. Using lagged independent variables and a sample of 150 metropolitan areas, we find that settlement patterns among immigrants are diverging from traditional patterns. That is, those metropolitan areas that had moderately high levels of globalization and lower costs of living as well as lower disadvantage indicators (e.g., percentage poverty) in 1990, had larger increases in percentage foreign‐born between 1990 and 2000 compared to areas with lower levels of globalization and higher costs of living and disadvantage. These trends suggest the increasing importance of second‐tier metropolises such as Atlanta, Phoenix, and Las Vegas in understanding where immigrants settle.     

Racial identity attitudes and interracial communication: Implications for social work practice in Britain

This paper is written from a psychological perspective and explores the relationship between black people's stages of racial identity development and interracial communication. It describes Cross's model of psychological nigrescence for black people and Helms's model of white identity development–in which she describes how whites go through the process of defining themselves as racial beings. Since the majority of social workers in Britain are white, it is argued that white identity development and its implication for interracial communication are important aspects to consider. It is argued that one's stage of racial identity may have a stronger impact on the communication process between white social workers and black clients than 'race' per se.     

Saddlepoint Approximations for the Difference of Order Statistics and Studentized Sample Quantiles

For a sample from a given distribution the difference of two order statistics and the Studentized quantile are statistics whose distribution is needed to obtain tests and confidence intervals for quantiles and quantile differences. This paper gives saddlepoint approximations for densities and saddlepoint approximations of the Lugannani–Rice form for tail probabilities of these statistics. The relative errors of the approximations are n ⁻¹ uniformly in a neighbourhood of the parameters and this uniformity is global if the densities are log-concave.     

ENCOUNTERS WITH STATISTICAL INFERENCE – AN INTERVIEW WITH EVAN WILLIAMS

Emeritus Professor Evan J. Williams was interviewed at the CSIRO Division of Mathematics and Statistics in Melbourne on 13 February 1991. Three major phases of his working life were discussed: time at CSIRO; time in the United States of America; time at The University of Melbourne. This article is based on an edited recording of the interview.     

Assessing the Quality of Knowledge in Social Care: Exploring the Potential of a Set of Generic Standards

Social care policy and practice draw on multiple sources ofknowledge. In order to help practitioners and policymakers identifyand act on the basis of high quality evidence, ways of assessingthe quality of this knowledge are needed. Part of the answermay lie in the use of a set of generic standards. To test thepotentiality of this approach, one document from each of fivecore domains of social care knowledge was selected and assessedindependently by three researchers using a set of generic standardsdeveloped within a study commissioned by the Social Care Institutefor Excellence. Critical reflections on feasibility and addedvalue were recorded. Each reviewer successfully applied theset of standards to each document, but faced problems with interpretationand the identification of source-specific standards. Use ofthe TAPUPAS schema forced consideration of the strengths andweaknesses of each document and broadened the common notionof quality and quality assessment to sources beyond the traditionalresearch domain. This small-scale testing suggests the potentialof the schema to enable assessments of quality to be appliedacross knowledge sources within both social care and other applieddiscipline areas such as health and education. As with any qualityassessment tool, training in its use is required.     

Generalized discriminant analysis based on distances

This paper describes a method of generalized discriminant analysis based on a dissimilarity matrix to test for differences in a priori groups of multivariate observations. Use of classical multidimensional scaling produces a low‐dimensional representation of the data for which Euclidean distances approximate the original dissimilarities. The resulting scores are then analysed using discriminant analysis, giving tests based on the canonical correlations. The asymptotic distributions of these statistics under permutations of the observations are shown to be invariant to changes in the distributions of the original variables, unlike the distributions of the multi‐response permutation test statistics which have been considered by other workers for testing differences among groups. This canonical method is applied to multivariate fish assemblage data, with Monte Carlo simulations to make power comparisons and to compare theoretical results and empirical distributions. The paper proposes classification based on distances. Error rates are estimated using cross‐validation.     

Empiricism, Symbolic Realism, and the Mystique of the Extreme*

The empiricist/symbolic realist debate in the sociology of religion, as well as the broader objectivist/subjectivist controversy in social science, suffers from the mystique of the extreme. Emphasis has been placed on the two approaches as opposing alternatives, an either-or choice. This paper suggests that the mystique of the extreme prohibits perception of the necessary, dialectical complementarity of the two approaches. Neither alone can succeed in understanding religion scientifically. Research efforts must bring together the two perspectives by using what social anthropologists refer to as the emic and etic levels of analysis.     

Nonmarital Fertility and the Effects of Divorce Rates on Youth Suicide Rates

Using pooled, time‐series data for a sample of 15 developed nations, we assess the effect of divorce rates on gender‐specific suicide rates for youths aged 15 – 19 with models of relative cohort size, lagged nonmarital fertility, and an interaction term for divorce rates and nonmarital fertility. The results reveal that, for young men, relative cohort size is positively related to suicide rates, and divorce rates interact with lagged nonmarital fertility. The interaction effect indicates that increases in divorces are especially consequential for suicide cohorts of male youths who were born in periods of high nonmarital fertility. For female youths, only divorce rates exert a significant effect on suicide rates, and it is a positive, main effect.