bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relating Individual Control, Social Understanding, and Gender to Child–Friend Interaction: A Relationships Perspective
Authors: McElwain Nancy L. , Volling Brenda L. 
Published: March 2003

Abstract According to a relationships perspective, it is critical to consider how the individual behaviors and characteristics of both partners shape their social interaction. Adopting a relationships approach to the investigation of children's friendships, we examined how preschool children's and their friends’ controlling behaviors, social understanding, and gender were related to their dyadic interaction. Child–friend dyads (n = 49) were videotaped in two laboratory play sessions (free play and sharing task), and child interviews assessed understanding of emotions and false beliefs. Both children's indirect control was associated with coordinated play during the free play session, and both children's direct control was associated with conflict during the sharing task. Moreover, dyadic interaction varied as a function of study children's social understanding, friends’ social understanding, and play session. An interaction between gender composition and play session also emerged for dyadic conflict. Multiple regression analyses suggested that study children's controlling behaviors accounted for associations between dyadic interaction and more ‘distal’ individual factors (i.e., social understanding, gender). The findings underscore the need to examine how both children's individual competencies are related to the quality of their dyadic interaction and illuminate how the associations between individual factors and dyadic interaction are moderated by the interactive context.
Shallow Water Wave Systems
Authors: Clarkson Peter A. , Priestley Thomas J. 
Published: March 2003

In this article we study various systems that represent the shallow water wave equation vxxt+αvvt−βvx∂x‐1(vt) −vt−vx = 0,where (∂x−1f)(x)=∫x∞f(y) dy, and α and β are arbitrary, nonzero, constants. The classical method of Lie, the nonclassical method of Bluman and Cole [J. Math. Mech. 18:1025 (1969)], and the direct method of Clarkson and Kruskal [J. Math. Phys. 30:2201 (1989)] are each applied to these systems to obtain their symmetry reductions. It is shown that for both the nonclassical and direct methods unusual phenomena can occur, which leads us to question the relationship between these methods for systems of equations. In particular an example is exhibited in which the direct method obtains a reduction that the nonclassical method does not.
Urban Education: Challenges in Educating Culturally Diverse Children
Authors: Zhou Min 
Published: March 2003

This article provides an overview of America's urban population based on the 2000 Census and the implications of increasing cultural diversity for urban public schools. It addresses three basic questions: 1. What does America's population look like at the beginning of the 21st century? 2. What challenges do children and their families face in this time of rapid demographic change? 3. What role can communities play in helping culturally diverse children do well in school? Current demographic trends indicate that ethnic minorities, especially immigrant groups, not only grow rapidly, but are also increasingly concentrated in urban areas, and that the level of residential segregation by race and class in 2000 remains as high as in 1990. Demographic shifts create new challenges for the education of racial minority and immigrant children. At issue is not whether children are able to advance beyond their parents’ status—many do so because their parents are insufficiently educated and are struggling at the society's bottom—but whether they can move up to and secure a position in the ranks of the American middle class. Research has shown that certain children living in the inner city are able to do well, despite adversarial conditions. A key difference is the availability and accessibility of community-based resources, such as after-school tutoring and other educationally oriented programs, that serve children.
Modelling spatial relationships between belgian car manufacturers and their suppliers using choremes
Authors: Cabus Peter 
Published: March 2003

Models are useful instruments to understand and explain reality. The modeller is looking for a model that, at the same time, represents spatial organisation in the most efficient, the most reliable and the most powerful way. This can only be obtained, however, when the modeller has a precise conception of the processes at stake.The starting point of the choreme model as Brunet conceived it is precisely the formulation of explicit hypotheses about the spatial organisation of society. In these hypotheses, the principle of dominance plays a major role. The choreme model was used to represent the networked territory that is the result of corporate strategy behind the network enterprise between Belgian car manufacturers and their supplying industry. The eventual model reveals that besides the principle of dominance, to which the car manufacturers’ decision power has to be assigned, the historically acquired territorial know‐how is the foundation of the geographical structure.
Reforming the WTO to Defuse Potential Trade Conflicts in Genetically Modified Goods
Authors: Perdikis Nicholas , Shelburne William A. Kerr , Hobbs Jill E. 
Published: March 2003

Arguably genetic modification is one of the most important technological change seen to date. Its effects on both human health and the environment are both profound and controversial. In particular consumers, mainly in the EU, have concerns regarding the long term effects of consuming genetically modified foods on their health. They are also concerned regarding the effect that genetically modified organisms will have on bio‐diversity and choice in the long run.Differing regulatory regimes towards genetically modified goods in the US and EU could lead to damaging trade conflicts. Current agreements covering trade in foods such as the SPS and TBT allow a way of diffusing conflicts. The primary aim of these agreements is, however, to prevent governments from protecting domestic producers by applying capricious barriers to foreign competition. This paper sets out to show that rather than modifying these two agreements it would be better to deal with new issues surrounding consumer preferences explicitly by negotiating a new international agreement.
The Development of the UK National Lottery: 1992–96
Authors: Moore Peter G. 
Published: March 2003

Summary
This paper outlines the build-up of the National Lottery launch, from the government 1992 white paper, the subsequent Parliamentary procedures leading to the National Lottery Act, the choice of Camelot as the operator in May 1994 and the nationwide launch of the lottery in November 1994. The paper outlines the achievements of the lottery and some longer-term issues that it faces.
Gender and Income Inequality in the UK 1968–90: The Feminization of Earnings or of Poverty?
Authors: Davies Hugh , Joshi Heather 
Published: March 2003

Summary
This paper uses data from the Family Expenditure Survey for five selected years between 1968 and 1990 to examine trends in the income distribution in the UK, highlighting the role of women’s labour force participation and earnings. The increased labour force participation of married women (especially mothers of young children in the 1980s) made a greater contribution to the decline of the ‘traditional’ male breadwinner family than the increased number of lone parents. The lower half of the distribution of weekly earnings became increasingly dominated by women. Though women’s weekly earnings remained low relative to men’s, the increase in their participation meant that, over the period, an increased share of family income came from women’s labour market income: in 1990 nearly a quarter of the income of families with children came from women’s earnings. Women’s earnings were an important factor in keeping families out of poverty. There was no trend towards increasing feminization of poverty over the sample period. Adult women were somewhat more likely to be poor than adult men were, but female-headed families were very much more likely to be in poverty, and much more dependent on state benefits, than male-headed families were. Women’s increased role in the labour market affected those in male-headed families more than those in female-headed families. Alongside a broad tendency for women’s earnings to reduce poverty and inequality, there is evidence that the female population has become more economically polarized.
Acquired Immune Deficiency Syndrome Projections in England and Wales: Interplay of Methodology and Data
Authors: De Angelis D. , Day N. E. , Gill O. N. 
Published: March 2003

Summary
Since the late 1980s, regular monitoring of the human immunodeficiency virus epidemic in England and Wales has been carried out through the work of successive national working groups. One of their tasks has been to provide short-term projections of the incidence of acquired immune deficiency syndrome. In this paper the data and methods used in this projection work are reviewed and results critically assessed with the aim of highlighting the strong interaction between methodological developments and data acquisition.
Measures of Mortality in the Study of Individuals Infected with the Human Immunodeficiency Virus in the UK Haemophilia Population
Authors: Darby S. C. , Ewart D. W. 
Published: March 2003

Summary
Two statistical issues that have arisen in the course of a study of mortality and disease related to the human immunodeficiency virus (HIV) in the haemophilia population of the UK are discussed. The first of these concerns methods of standardization for age and it is shown that, when the mortality of HIV-infected individuals with different severities of haemophilia are compared, an analysis based on the ratio of observed to national expected deaths suggests that mortality in HIV-infected individuals depends on the severity of their haemophilia. This conclusion is inappropriate and mortality in HIV-infected individuals is, in fact, similar regardless of severity of haemophilia. The second part of the paper discusses the effect of using various end points for studies of survival and progression of HIV-related disease. In the present example it was possible to calculate relative survival in HIV-infected individuals, i.e. survival after correcting for mortality expected in the absence of HIV infection. An analysis based on absolute survival gave a very similar picture of the effect of age at infection to an analysis based on relative survival, whereas an analysis based on the time to diagnosis of acquired immune deficiency syndrome (AIDS) underestimated the effect substantially and the possible alternative end point of time to AIDS or HIV-related death was shown to be subject to considerable misclassification error.
Issues in the Design and Analysis of Therapeutic Trials in Human Immunodeficiency Virus Infection
Authors: Babiker A. , Darbyshire J. , Peto T. , Walker S. 
Published: March 2003

Summary
The first randomized trial of antiviral therapy in human immunodeficiency virus (HIV) disease included 282 patients with acquired immune deficiency syndrome (AIDS) or AIDS-related complex and was stopped in 1986 after an average follow-up of 4 months because of a substantial reduction in mortality in the group who received zidovudine (AZT). The era of anti-HIV treatment had begun. This paper discusses some of the difficulties which have emerged over the subsequent 10 years as new anti-HIV drugs have been developed requiring evaluation in clinical trials. The trials in which the British Medical Research Council has played a major role (the Concorde, Alpha and Delta trials) and some of the key trials conducted by the AIDS Clinical Trials Group (ACTG) (the ACTG 019 and ACTG 175 trials) and the Community Programs for Clinical Research on AIDS (CPCRA) (the CPCRA 007 trial) in the US will be used to illustrate some of the issues faced by clinical trialists and governmental regulatory agencies in the evaluation of therapies for a disease which, in spite of advances in therapy, still has a high mortality.
Epidemiology and Litigation—The Sellafield Childhood Leukaemia Cases
Authors: Wakeford R. 
Published: March 2003

Summary
Statisticians and scientists are often required to provide information outside the scientific community. One important example is as an expert witness in the law courts. The civil litigation cases of Reay versus British Nuclear Fuels plc and Hope versus British Nuclear Fuels plc are a vivid illustration of how science and scientists interact with the law and lawyers. The personal injury cases were decided on the basis of how a specific epidemiological association should be properly interpreted, and this involved many experts. It is desirable that statisticians and scientists understand the nature of expert evidence, and these two cases are used to illuminate the role of the scientist in civil litigation.
Dealing with Non-Ignorable Non-Response by Using an ‘Enthusiasm-to-Respond’ Variable
Authors: Copas A. J. , Farewell V. T. 
Published: March 2003

Summary
In the National Survey of Sexual Attitudes and Lifestyles (NATSSAL), it is recognized that non-response is unlikely to be ignorable. In some surveys, in addition to the response variables of interest, there may also be an ‘enthusiasm-to-respond’ variable which is expected to be related to the probabilities of item and unit response. Inference techniques to deal with non-ignorable non-response, based on a propensity-to-respond score, can be developed when there are both item and unit non-responders. For the NATSSAL data, an interviewer-measured interviewee embarrassment variable is combined with demographics to produce a score for the propensity to respond. The necessary likelihood development is outlined and alternative approaches to interval estimation are compared. The methodology is illustrated through an estimation of virginity from NATSSAL data.
Forecasting on British Election Night 1997
Authors: Brown P. J. , Firth D. , Payne C. D. 
Published: March 2003

Summary
An account is given of methods used to predict the outcome of the 1997 general election from early declared results, for use by the British Broadcasting Corporation (BBC) in its election night television and radio coverage. Particular features of the 1997 election include extensive changes to constituency boundaries, simultaneous local elections in many districts and strong tactical voting. A new technique is developed, designed to eliminate systematic sources of bias such as differential refusal, for incorporating prior information from the BBC’s exit poll. The sequence of forecasts generated on election night is displayed, with commentary.
A Multilevel Analysis of Longitudinal Ordinal Data: Evaluation of the Level of Physical Performance of Women Receiving Adjuvant Therapy for Breast Cancer
Authors: Ribaudo Heather J. , Bacchi M. , Bernhard J. , Thompson S. G. 
Published: March 2003

Summary
Longitudinal health-related quality-of-life (QOL) data are often collected as part of clinical studies. Here two analyses of QOL data from a prospective study of breast cancer patients evaluate how physical performance is related to factors such as age, menopausal status and type of adjuvant treatment. The first analysis uses summary statistic methods. The same questions are then addressed using a multilevel model. Because of the structure of the physical performance response, regression models for the analysis of ordinal data are used. The analyses of base-line and follow-up QOL data at four time points over two years from 257 women show that reported base-line physical performance was consistently associated with later performance and that women who had received chemotherapy in the month before the QOL assessment had a greater physical performance burden. There is a slight power gain of the multilevel model over the summary statistic analysis. The multilevel model also allows relationships with time-dependent covariates to be included, highlighting treatment-related factors affecting physical performance that could not be considered within the summary statistic analysis. Checking of the multilevel model assumptions is exemplified.
Classical Multilevel and Bayesian Approaches to Population Size Estimation Using Multiple Lists
Authors: Fienberg S. E. , Johnson M. S. , Junker Brain W. 
Published: March 2003

Summary
One of the major objections to the standard multiple-recapture approach to population estimation is the assumption of homogeneity of individual ‘capture’ probabilities. Modelling individual capture heterogeneity is complicated by the fact that it shows up as a restricted form of interaction among lists in the contingency table cross-classifying list memberships for all individuals. Traditional log-linear modelling approaches to capture–recapture problems are well suited to modelling interactions among lists but ignore the special dependence structure that individual heterogeneity induces. A random-effects approach, based on the Rasch model from educational testing and introduced in this context by Darroch and co-workers and Agresti, provides one way to introduce the dependence resulting from heterogeneity into the log-linear model; however, previous efforts to combine the Rasch-like heterogeneity terms additively with the usual log-linear interaction terms suggest that a more flexible approach is required. In this paper we consider both classical multilevel approaches and fully Bayesian hierarchical approaches to modelling individual heterogeneity and list interactions. Our framework encompasses both the traditional log-linear approach and various elements from the full Rasch model. We compare these approaches on two examples, the first arising from an epidemiological study of a population of diabetics in Italy, and the second a study intended to assess the ‘size’ of the World Wide Web. We also explore extensions allowing for interactions between the Rasch and log-linear portions of the models in both the classical and the Bayesian contexts.
Prospective Time Periodic Geographical Disease Surveillance Using a Scan Statistic
Authors: Kulldorff Martin 
Published: March 2003

Summary
Most disease registries are updated at least yearly. If a geographically localized health hazard suddenly occurs, we would like to have a surveillance system in place that can pick up a new geographical disease cluster as quickly as possible, irrespective of its location and size. At the same time, we want to minimize the number of false alarms. By using a space–time scan statistic, we propose and illustrate a system for regular time periodic disease surveillance to detect any currently ‘active’ geographical clusters of disease and which tests the statistical significance of such clusters adjusting for the multitude of possible geographical locations and sizes, time intervals and time periodic analyses. The method is illustrated on thyroid cancer among men in New Mexico 1973–1992.
Dropping Out of University: A Statistical Analysis of the Probability of Withdrawal for UK University Students
Authors: Smith Jeremy P. , Naylor Robin A. 
Published: March 2003

Summary
From individual level data for an entire cohort of undergraduate students in the ‘old’ universities in the UK, we use a binomial probit model to estimate the probability that an individual will ‘drop out’ of university before the completion of their degree course. We examine the cohort of students enrolling full time for a 3- or 4-year degree in the academic year 1989–1990. We find evidence to support both the hypothesis that the completion of courses by students is influenced by the extent of prior academic preparedness and the hypothesis that social integration at university is important. We also find an influence of unemployment in the county of prior residence, especially for poorer male students. Finally, we draw conclusions regarding the public policy of constructing university performance indicators in this area.
Estimating Reference Ranges from Stratified Two-stage Samples
Authors: Thompson Mary Lou , Edland Steven D. , Gibbons Laura E. , McCurry Susan M. 
Published: March 2003

Summary
We present methodology for estimating age-specific reference ranges by using data from two-stage samples. On the basis of the information obtained in the first stage, the initial sample is stratified and random subsamples are drawn from each stratum, where the selection probabilities in this second-stage sampling may be different across strata in the population. The variable for which the reference ranges are to be established is measured at the second phase. The approach involves maximum likelihood estimation of the parameters of the age-specific distributions and separate estimation of the population stratum probabilities. These are combined to yield estimates of the quantiles of interest. The issue of variance estimation for the estimated quantiles is also addressed. The methodology is applied to the estimation of reference ranges for a cognitive test score in a study of non-demented older Japanese-Americans.
Analysis of Incomplete Durations with Application to Contraceptive Use
Authors: Ali Mohamed M. , Marshall Tom , Babiker Abdel G. 
Published: March 2003

Summary
Models for analysing incomplete durations obtained from cross-sectional surveys are presented. The aim of the paper is to develop a framework for analysing the incomplete duration of episodes in progress at the time of the survey by formulating generalized linear models and fitting and assessing them by using standard statistical packages. The maximum quasi-likelihood method is used for model fitting. The choice of the distribution and the diagnostic procedures are discussed. Simulated data from two distributions (the Weibull and log-logistic distributions) are used to evaluate the methodology developed and to assess model misspecifications. A data set on the current use of the contraceptive pill from a cross-sectional survey in Egypt is analysed.
New Methods for Comparing Literacy Across Populations: Insights from the Measurement of Poverty
Authors: Denny Kevin 
Published: March 2003

SummaryThis paper analyses levels of low literacy across 12 countries by using the International Adult Literacy Survey. We go beyond existing work that only looks at the proportions below certain critical levels of literacy. Using methods developed for the measurement of poverty we calculate measures of literacy that are sensitive to the distribution of literacy within those defined as illiterate. This reveals a different pattern of the extent of literacy problems across countries and within some populations. These measures should be useful to policy makers who need to allocate resources to alleviate low literacy and numeracy.