The seasonality of conception

Individual data on menstrual cycles of noncontracepting women living in Western countries were used in order to verify whether the biological seasonality of conception persists after sexual behavior is controlled for. Episodes of intercourse were recorded daily, and the time of ovulation was detected by a marker We find that the seasonality of conception changes with woman's age and frequency of episodes of sexual intercourse. In particular; for women aged 27-31 having only one act of intercourse during the six most fertile days of the menstrual cycle, the seasonality of fecundability is stronger In this age group in the Northern Hemisphere, if seasonality of acts of sexual intercourse is controlled, the monthly distribution of probability of conception is bimodal, with two maxima (September and January) and two minima (December and March). When unobserved characteristics of the couples are considered, this seasonal pattern of conception persists.     

Extreme value regression models: a useful reparameterization for the survival function

In this paper, we consider some aspects of accurate approximate inferences for the survival function at a specifed time t 0 , considering extreme value regression models using a modified form of reparameterization proposed by Guerrero and Johnson, and exploring a non-normality measure for likelihood functions and posterior densities introduced by Kass and Slate. We illustrate the proposed methodology, considering a lifetime data set with two treatments introduced by Lee.     

Regulatory fit effects on perceived fiscal exchange and tax compliance

Paying taxes can be considered a contribution to the welfare of a society. But even though tax payments are redistributed to citizens in the form of public goods and services, taxpayers often do not perceive many benefits from paying taxes. Information campaigns about the use of taxes for financing public goods and services could increase taxpayers’ understanding of the importance of taxes, strengthen their perception of fiscal exchange and consequently also increase tax compliance. Two studies examined how fit between framing of information and taxpayers’ regulatory focus affects perceived fiscal exchange and tax compliance. Taxpayers should perceive the exchange between tax payments and provision of public goods and services as higher if information framing suits their regulatory focus. Study 1 supported this hypothesis for induced regulatory focus. Study 2 replicated the findings for chronic regulatory focus and further demonstrated that regulatory fit also affects tax compliance. The results provide further evidence for findings from previous studies concerning regulatory fit effects on tax attitudes and extend these findings to a context with low tax morale.     

Expert and Public Perception of Risk from Biotechnology

Risk perceptions of a series of biotechnology applications were examined in a public (nonexpert) sample and an expert sample. Compared with the experts, the public perceived all biotechnology applications as more risky. Both groups perceived food-related applications to be riskier than medical applications. Compared with the public, experts perceived both food and medical applications as less harmful and more useful. Experts also judged the risks posed from medical biotechnology applications as more familiar and acknowledged by people and science. Lay estimates of the risk of food applications were predicted by potential harm, potential benefits, science knowledge, and familiarity; experts' estimates were predicted only by harm and benefits. Lay estimates of the risk of medical applications were predicted by potential harm; experts' estimates were predicted by potential benefits, number and type of people exposed, and science knowledge. We discuss the implications of the results for risk communication about and management of different types of biotechnologies.     

Multicriteria decision making applied to waste recycling in Brazil

Waste management, like other environmental issues, tends to be a suitable topic for problem solving using multicriteria decision-making techniques when uncertainty is involved. This paper presents two cases where the decision makers had different preferences. In the first case, social agents required an evaluation of different disposal alternatives for plastic waste. In the second case, existing construction and demolition waste recycling facilities required a performance evaluation.     

Working systemically following abuse: exploring safe uncertainty

This paper explores systemic practice and ‘safe uncertainty’ in work with parents who do not accept responsibility following child abuse. The prevailing view has been that little positive work can be carried out with families where responsibility is denied. Our work is offered to add to the small yet growing number of publications which challenge the dominant discourse relating to child protection work. A case study is illustrated within which the issue of assessment versus therapy emerges. The Legal Department of the Local Authority Social Services requested an assessment from child and family psychiatry. Concern developed regarding the point at which assessment ended and therapy began. The authors offer a systemic model in exploring the importance of a safe multi‐disciplinary framework within which uncertainty can be tolerated and therapy/change work can be affected. A framework within which parents can be supported in developing skills to meet the needs of children is presented. These issues are central to the professional and legal systems relating to child protection in the UK. Copyright © 1999 John Wiley & Sons, Ltd.