Measuring density dependence in survival from mark-recapture data

We discuss the analysis of mark-recapture data when the aim is to quantify density dependence between survival rate and abundance. We describe an analysis for a random effects model that includes a linear relationship between abundance and survival using an errors-in-variables regression estimator with analytical adjustment for approximate bias. The analysis is illustrated using data from short-tailed shearwaters banded for 48 consecutive years at Fisher Island, Tasmania, and Hutton's shearwater banded at Kaikoura, New Zealand for nine consecutive years. The Fisher Island data provided no evidence of a density dependence relationship between abundance and survival, and confidence interval widths rule out anything but small density dependent effects. The Hutton's shearwater data were equivocal with the analysis unable to rule out anything but a very strong density dependent relationship between survival and abundance.     

The Trouble with Harry: Why the 'New Agenda of Life Politics' Fails to Convince

via e-mail: paul.garrett{at}nottingham.ac.uk Summary Harry Ferguson (2001), referring largely to Britain and Ireland,maintains that social work should be committed to a ‘newway of thinking’ which is rooted in ‘life politics’.This idea, uncritically grounded in the ideas of Anthony Giddensand Ulrich Beck, fails to convince because: the assertion thatwe are now living in a ‘post traditional order’is undermined by the resilience of key historical forms of regulationand control which continue, for example, to limit women's choicein the sphere of reproductive rights; identified changes inthe texture of family relations are not evidenced by research;the ‘life politics’ perspective places too greatan emphasis on human agency, choice and volition and not enoughon structural constraint; the structural location of the ‘lifepolitics’ proponents is not interrogated; the analysisis too stridently dismissive of the idea that ‘emancipatorypolitics’ should be social work's primary orientation.     

The Current State of Women Print Journalists: An Analysis of the Status and Careers of Females in Newspapers Sports Departments

The purpose of this study was to provide an analysis of the current state of women journalists within the sports departments at newspapers across the United States. This investigation involved a determination of their demographic make-up, job status within the sports department, rationale for entering the field, and advice for younger women preparing to follow in their footsteps. The findings suggest that although the large majority of women have faced discrimination in the sport media, they believe improvements have been made towards equity. The majority of respondents noted that they were happy with the assignments they had been given. Subjects did, however, feel that they were assigned to cover females more than their male counterparts, and some responses regarding dissatisfaction with their positions was also noted.     

Intermarriage and the risk of divorce in the Netherlands: the effects of differences in religion and in nationality, 1974-94

A textbook hypothesis about divorce is that heterogamous marriages are more likely to end in divorce than homogamous marriages. We analyse vital statistics on the population of the Netherlands, which provide a unique and powerful opportunity to test this hypothesis. All marriages formed between 1974 and 1984 (nearly 1 million marriages) are traced in the divorce records and multivariate logistic regression models are used to analyse the effects on divorce of heterogamy in religion and national origin. Our analyses confirm the hypothesis for marriages that cross the Protestant-Catholic or the Jewish-Gentile boundary. Heterogamy effects are weaker for marriages involving Protestants or unaffiliated persons. Marriages between Dutch and other nationalities have a higher risk of divorce, the more so the greater the cultural differences between the two groups. Overall, the evidence supports the view that, in the Netherlands, new group boundaries are more difficult to cross than old group boundaries.     

An exploratory study examining the spatial dynamics of illicit drug availability and rates of drug use

This study examines the spatial relationship between drug availability and rates of drug use in neighborhood areas. Responses from 16,083 individuals were analyzed at the zip code level (n = 158) and analyses were conducted separately for youth and adults using spatial regression techniques. The dependent variable is the percentage of respondents using drugs in the past year. Neighborhood drug availability (the major independent variable) was measured by the percentage of non-drug users who had been approached to purchase drugs. Data were obtained as part of the Fighting Back community evaluation. For youth (aged 12 to 18), drug sales in adjacent and surrounding areas were positively associated with self-reported drug use in areas where youth were residents. For adults, drug sales within the neighborhood were negatively associated with drug use, while drug sales in immediately adjacent neighborhoods were positively related to self-reports of drug use. Findings suggest that the areas where rates of drug users are greatest are not necessarily the same area where drugs are sold. Designing strategies to reduce the supply of drugs should receive input from city and regional planners and developers, as well as law enforcement and public health professionals.     

Movement patterns of Blanding's turtles (Emydoidea blandingii) in the suburban landscape of eastern Massachusetts

We studied Blanding's turtle Emydoideablandingii home range and seasonal movement patterns at 10 sites in suburban eastern Massachusetts during 2001 and 2002. Radio telemetry was used to track 51 turtles (31 females and 20 males) and home range was estimated during 4 seasonal activity periods usingthe 95% fixed kernel estimator. Sex, year, and site were not found to affect home range size due to the large amount of variationbetween and within individuals. There were significant differences in home range length between activity periods, with longest movementsoccurring during the period of 15 April to 31 May as animals moved to ephemeral wetlands. Mean annual home range size for Blanding's turtles was 22 ha, and mean home range length was 856 m. Animals frequently had annual home ranges that overlapped little from year to year, indicating that our calculations greatly underestimate the lifetime home range of an individual. Due to the large area needs of Blanding's turtles, and the diversified ownership of lands in eastern Massachusetts, numerous stakeholders will need to be involved to effectively protect viable populations for the foreseeable future.     

Computation of exact confidence intervals from discrete data using studentized test statistics

A new area of research interest is the computation of exact confidence limits or intervals for a scalar parameter of interest from discrete data by inverting a hypothesis test based on a studentized test statistic. See, for example, Chan and Zhang (1999), Agresti and Min (2001) and Agresti (2003) who deal with a difference of binomial probabilities and Agresti and Min (2002) who deal with an odds ratio. However, neither (1) a detailed analysis of the computational issues involved nor (2) a reliable method of computation that deals effectively with these issues is currently available. In this paper we solve these two problems for a very broad class of discrete data models. We suppose that the distribution of the data is determined by (,) where is a nuisance parameter vector. We also consider six different studentized test statistics. Our contributions to (1) are as follows. We show that the P-value resulting from the hypothesis test, considered as a function of the null-hypothesized value of , has both jump and drop discontinuities. Numerical examples are used to demonstrate that these discontinuities lead to the failure of simple-minded approaches to the computation of the confidence limit or interval. We also provide a new method for efficiently computing the set of all possible locations of these discontinuities. Our contribution to (2) is to provide a new and reliable method of computing the confidence limit or interval, based on the knowledge of this set.     

Capabilities and Well-Being: Evidence Based on the Sen–Nussbaum Approach to Welfare

One of the most significant theoretical contributions to welfare analysis across a range of disciplines has been the development of the capabilities framework by Sen and others. Motivated by the claim that freedom should play a key role in social evaluation, the capabilities framework suggests that we consider what it is that people are free to do, as well as what they actually do. Using data from the British Household Panel Survey in conjunction with a list of substantial values posited by Martha Nussbaum, we contribute to the operationalisation and testing of this approach. Specifically, we suggest that commonly used secondary data sources do provide some information about the capabilities people have and that this can be incorporated into models of (subjective) well-being such as those used by a growing number of labour and health economists. We find evidence that a wide range of capabilities exhibit statistically significant relations to well-being that the relations are complex and slightly different for men and women, and conclude with suggestions for future developments.     

An Empirical Taxonomy of SOE Governance in Transitional China

China’s State-Owned Enterprises (SOEs) traditionally have been governed by the Communist Party. Privatization has brought greater numbers of investors who have a stake and demand a voice in how SOEs are managed. Three traditional governance perspectives are agency theory, resource dependence, and institutional theory, but China’s transition introduces several additional governance approaches. Are “capitalism with Chinese characteristics” and “bureaucratic entrepreneurialism” paradoxes? Based on initial interviews of SOE executives, a survey of top managers and board chairs of listed companies, and subsequent interviews and observations in select case companies, this paper develop a taxonomy of SOE governance that now exists in China. Two of the approaches represent the extremes of the old state-centered regimes and the new shareholder-centered regimes. Considering China’s historical and cultural contexts coupled with its current stage of economic transition, two additional approaches to corporate governance are to have a vacuum as neither the state nor shareholders dominate or – in unique contrast to other countries – a hybrid of both.