Pre‐procreative ages in population stability and cyclicity

Age‐specific models of population renewal (with and without feedback) which imply convergence to a stable state for some levels of fertility or feedback may imply the presence of long‐term cycling around a constant or exponentially changing equilibrium for other levels of fertility or feedback. The switch from one regime to the other is a “bifurcation.”; The conditions for bifurcation involve the roots of an analogue of Lotka's Equation.

Typically bifurcation is induced by raising the strength of feedback or the level of fertility. It has been known since the early 1980s, however, that this is sometimes impossible. It is sometimes impossible even with the linear renewal equation itself and with the most basic of non‐linear models, Lee's cohort feedback model.

Here it is proved that this typical route to bifurcation does not fail for these basic models in the presence of a condition which always holds for realistic applications with higher organisms: the existence of a span of ages before the onset of fertility.

Specifically, a strictly positive lower bound on ages of procreation is proved to be sufficient to guarantee the existence of a rescaling of Lotka's Equation for which the real part of some complex root vanishes. This result holds for absolutely Lebesgue‐integrable (signed) net maternity functions on the positive real line and for absolutely summable (signed) net maternities on the positive integers.

It follows that Coale's rescaling device for the analysis of approach to stability in stable population theory can be implemented for all realistic human net maternity schedules. It also follows that the many special cases of the cohort feedback model throughout population biology will all generate persistent cycling instead of stability if feedback is sufficiently strong.     

Pre-term Foetal Life Times in Scotland

A proportional hazards model was used to evaluate the association between ten categorical covariates and the risk of pre-term delivery for women having their first child and women in subsequent pregnancies. An adaptation of the model for use with grouped survival times made it possible to model foetal life times between 28 and 36 completed weeks of gestation for 67,000 Scottish singleton births in 1981. The use of the model was justified by testing time-dependent effects. For both groups of women age, and a history of abortion, were major factors associated with increased hazard. For women experiencing a second or higher-order birth a history of perinatal death was also associated with substantially increased hazard to the pregnancy.     

The application of a performance management system in hospitals: A hypothetical example

Abstract

The central theme of this article is performance management, defined as activities of organizations aimed at an effective and efficient use of their human resources. The organization focused on in particular is the hospital. Three principles taken from motivation theory are dealt with which are basic to performance management: goal setting, feedback and reinforcement. Next, a recently developed procedure (Pritchard 1990, Pritchard et al. 1988, 1989) for the design of performance management systems is described. This procedure, ProMES: Productivity Measurement and Enhancement Systems, is explained using a team of ward nurses as a hypothetical example. In addition to the nursing wards example, other potential applications of the ProMES technique to several hospitals areas are mentioned. Finally, some conditions that should be fulfilled in order to successfully start a ProMES project are discussed.     

Asymptotocally nonparametric tests with censored paired data

A class of asymptotically nonparametric test with contains a test proposed by Wei(1980), is considered for testing the equality of two continuous distribution funcitons when paired observations are subject to arbitrary right censorship. It is shown that under the null hypothesis each test statistic converges in distribution to the standard normal random variable. Furthermore. the Monte Carlo simulation results indicate that some tests in this class are more powerful than Wei's test. A generalization to incomplete censored paired data is also included.     

Contraceptive Responsibility among Male University Students

Abstract

This paper assesses the male contribution to contraceptive mismanagement and unwanted pregnancy. The subjects were 109 students at the University of Melbourne. A high incidence of risk-taking was reported, and almost one-fifth of the sexually experienced men stated that they had been involved in an unwanted pregnancy. A small group of these reported more than one such incident. The underlying reasons for poor contraceptive technique seemed to be related to two beliefs: that contraception is a female responsibility, and that sexual intercourse should be entirely spontaneous and unplanned.     

Debt‐Relief Effectiveness and Institution‐Building

This article provides new evidence on the effects of recent debt‐relief programmes on different macroeconomic indicators in developing countries, focusing on the Heavily Indebted Poor Countries (HIPCs). The relationship between debt relief and institutional change is also investigated to assess whether donors are moving towards ex‐post governance conditionality. Results show that debt relief is only weakly associated with subsequent improvements in economic performance but is correlated with increasing domestic debt which undermines the positive achievements in reducing external debt service. There is also evidence that donors are moving towards a more sensible allocation of debt forgiveness, rewarding countries which have better policies and institutions.     

Media and the Intersectional Other

This article presents the findings of an intersectional study on migrant women on German television. Besides content and textual analyses, we conducted focus groups with audiences and interviews with migrant media workers. As the representation of Others was explored through the nodes of production, consumption, and identity, a complicated intersectional practice emerged. We found the televised representations of migrant women to be dominated by (often veiled) women as signifiers of non-integration but also by instances when gendered ethnicity was used as a marketable attribute. The audiences and producers employed various distancing strategies: they criticized specific programs for blatant stereotyping as much as didactic counter-stereotyping while downplaying systemic shortfalls of the coverage. These distancing strategies were intensified by the acceptance of individualized ideologies of success and commodified logics of media production. Ultimately, class appeared as the central demarcating category. On German television a problematic class distinction was articulated through ethnic and gender difference. Female migrants were often “othered” as lower-class. This class discourse absolved middle-class viewers and media workers from engaging in the systemic struggles over female/migrant identities, thus undermining the potential for gender and migrant solidarity and for the dynamic creation of cultural citizenship as a mode of belonging.     

Die Bedeutung der Zinsschranke

The German Corporate Tax Reform Act of 2008 requires an adjustment of classic valuation concepts because it limits interest deduction from taxable income depending on the operating performance of the company. By using time- and state-contingent discount rates in a risk-neutral valuation with predetermined debt levels, a theoretically sound valuation result is obtained. However, a modified APV-concept which assumes deterministic debt over the planning horizon and constant leverage in the terminal value phase also yields consistent valuation results when two types of tax shields with different levels of risk are distinguished.