Missing data estimators in the general linear model: an evaluation of simulated data as an experimental design

Previous simulations have reported second order missing data estimators to be superior to the more straightforward first order procedures such as mean value replacement. These simulations however were based on deterministic comparisonsbetween regression criteria even though simulated sampling is a random procedure. In this paper a simulation structured asan experimental design allows statistical testing of the various missing data estimators for the various regression criteria as well as different regression specifications. Our results indicate that although no missing data estimator is globally best many of the computationally simpler first order methods perform as well as the more expensive higher order estimators, contrary to some previous findings.     

New methodologies for the 2001 Census in England and Wales

This paper looks at the significant innovations that are being introduced into the 2001 Census in England and Wales. Whilst the traditional concept of collecting information from each person and household in the country at a fixed point is being adhered to, in virtually every other respect the Census in 2001 will be very different from those that have preceded it.     

Environmental Equity: The Demographics of Dumping

Research addressing “environmental equity” and “environmental racism” claims that facilities for treatment, storage, and disposal of hazardous wastes (TSDFs) are located disproportionately in minority areas. In the first comprehensive study of TSDFs to use census tract-level data, we find no nationally consistent and statistically significant differences between the racial or ethnic composition of tracts which contain commercial TSDFs and those which do not. TSDFs are more likely to be found in tracts with Hispanic groups, primarily in regions with the greatest percentage of Hispanics. Different geographic units of analysis elaborate on, but are consistent with, these results.     

Integrating post-qualification study into the workplace: The candidates' experience

The PQ framework for qualified social workers has struggled to become consistently established within workplace training and practice organisations across the UK. This is likely to become a focus for change as the Government reviews current structures and attempts to 'modernise the workforce' by encouraging the creation of cultures of post-qualification learning and continuing professional development [PQ/CPD]. This paper argues that the current emphasis upon the rhetoric of 'performance management' needs to be balanced by attention to the realities of integrating operational and professional development demands within socio-cultural contexts. This paper reports and discusses the results of a questionnaire survey into the experiences of registered PQ candidates within a Local Authority SSD. A summary of key results is provided. The discussion identifies a number of themes and strategies for integrating PQ into the workplace. These are based upon a range of attitudinal and practical factors, such as decision-making; supervision; study arrangements; mentoring; and motivation, that cover some of the experiences of candidates. The paper concludes by drawing parallels with similar developments within nursing and recommends that all stakeholders involved in PQ development need to help establish the conditions within practice contexts where social workers can link service and policy initiatives with the requirements for post-qualification study.     

Fertility in Kenya and Uganda: A comparative study of trends and determinants

Between 1980 and 2000 total fertility in Kenya fell by about 40 per cent, from some eight births per woman to around five. During the same period, fertility in Uganda declined by less than 10 per cent. An analysis of the proximate determinants shows that the difference was due primarily to greater contraceptive use in Kenya, though in Uganda there was also a reduction in pathological sterility. The Demographic and Health Surveys show that women in Kenya wanted fewer children than those in Uganda, but that in Uganda there was also a greater unmet need for contraception. We suggest that these differences may be attributed, in part at least, first, to the divergent paths of economic development followed by the two countries after Independence; and, second, to the Kenya Government's active promotion of family planning through the health services, which the Uganda Government did not promote until 1995.     

Spinoza in the history of cultural psychology and activity theory

ABSTRACT

This review of the place of Spinoza in the history of cultural-historical activity theory begins with a synopsis of Ilyenkov’s influential essay “Spinoza—Thought as an Attribute of Substance” and adds further points. I go on to look at the historical context of Spinoza’s work, the mixed character of his legacy, and the need to see Spinoza as one moment in an entire historical development.     

Diagnostic Displays for Assessing Leverage and Influence in Generalized Linear Models

A general technique for assessing leverage and influential observations in Generalized Linear Models is described. The procedure takes the form of Half-Normal plots with envelopes derived from simulation to enhance overall assessment of the model. This procedure of assessment is more informative and provides additional insight compared with procedures based on the largest sample leverage and influence statistics. Application of the method is illustrated with an example in logistic regression.