Approximating the risk score for disease diagnosis using MARS

In disease screening and diagnosis, often multiple markers are measured and combined to improve the accuracy of diagnosis. McIntosh and Pepe [Combining several screening tests: optimality of the risk score, Biometrics 58 (2002), pp. 657–664] showed that the risk score, defined as the probability of disease conditional on multiple markers, is the optimal function for classification based on the Neyman–Pearson lemma. They proposed a two-step procedure to approximate the risk score. However, the resulting receiver operating characteristic (ROC) curve is only defined in a subrange (L, h) of false-positive rates in (0,1) and the determination of the lower limit L needs extra prior information. In practice, most diagnostic tests are not perfect, and it is usually rare that a single marker is uniformly better than the other tests. Using simulation, I show that multivariate adaptive regression spline is a useful tool to approximate the risk score when combining multiple markers, especially when ROC curves from multiple tests cross. The resulting ROC is defined in the whole range of (0,1) and is easy to implement and has intuitive interpretation. The sample code of the application is shown in the appendix.     

Reliability acceptance sampling plans for the Weibull distribution under accelerated Type-I censoring

Type-I censored reliability acceptance sampling plans (RASPs) are developed for the Weibull lifetime distribution with unknown shape and scale parameters such that the producer and consumer risks are satisfied. It is assumed that the life test is conducted at an accelerated condition for which the acceleration factor (AF) is known, and each item is continuously monitored for failure. Sensitivity analyses are also conducted to assess the effect of the uncertainty in the assumed AF on the actual producer and consumer risks, and a method is developed for constructing RASPs that can accommodate the uncertainty in AF.     

Transfer Pricing in Transition Economies: Evidence from Ukraine

Faced with possibilities and challenges of doing business under different regulatory regimes, transnational corporations have developed a number of transfer mechanisms to take advantage of profit maximization opportunities. Transfer pricing is a transfer mechanism widely used by transnational corporations. Implications of transfer pricing for profitability and the need for transfer pricing regulation are well understood by national governments, which is reflected in the fact that more than 60 governments have introduced some form of transfer pricing controls. Transfer pricing is a challenging issue for transition economies as their transfer pricing regulatory systems are less mature than those of developed countries. The authors have initiated an empirical study on transfer pricing strategies in the Ukrainian market. In addition, the national regulatory regime for transfer pricing was evaluated compared to international best practices. This article is an attempt to draw attention of the research community and Ukrainian policy-makers to transfer pricing issues in Ukraine.      

中国老年人虚弱指数与死亡风险及队列差异

利用中国老年人健康长寿影响因素调查（ CLHLS ）2002－2011年跟踪调查数据,通过多种健康指标构建中国老年人虚弱指数,运用增长曲线模型和Cox等比例风险函数的研究方法,对中国老年人虚弱指数和死亡风险及其队列差异进行了深入分析。研究发现,女性虚弱指数比男性高,增长速度也比男性快,但是死亡风险比男性低;出生较晚的队列与出生早的队列相比,虚弱指数会更高,他们的增长程度更快;受教育程度高的老年人虚弱指数低,但是其增长速度却比受教育程度低的老年人要高。     

Risk Regulation in High-Conflict Parenting

That “there is no gathering of roses without risking the thorns” might be the simplest way to think of the paradox of relationship. Risk regulation as psychological mechanism minimizes rejection (thorns) and maximizes assurance (roses). In the article, the social psychology of risk regulation is set in the context of divorce and high-conflict parenting. Risk regulation provides not only guidance for treatment, but also a conceptual framework for professional opinion in forensic evaluation and legal consideration.     

Some novel results on pairwise quasi-asymptotical independence with applications to risk theory

In this article we obtain some novel results on pairwise quasi-asymptotically independent (pQAI) random variables. Concretely speaking, let X₁, …, X_n be n real-valued pQAI random variables, and W₁, …, W_n be another n non negative and arbitrarily dependent random variables, but independent of X₁, …, X_n. Under some mild conditions, we prove that W₁X₁, …, W_nX_n are still pQAI as well. Our result is in a general setting whether the primary random variables X₁, …, X_n are heavy-tailed or not. Finally, a special case of above result is applied to risk theory for investigating the finite-time ruin probability for a discrete-time risk model with a wide type of dependence structure.     

Peer paradox: the tensions that peer relationships raise for vulnerable youth

The contribution peer relationships make to positive adolescent development is well recognized. Accordingly, peer problem measures typically assess youth with few age‐appropriate peers as having peer problems. Yet, youth facing high levels of personal and/or social adversity may reduce their association with antisocial peers as part of coping or risk mitigation strategies. While such strategies will result in higher scores on peer problem measures, they may also facilitate resilience and constitute a resource social workers can draw on in their work with youth. To test this proposition of peer adaptation as a risk mitigation strategy, mixed‐methods data relating to two groups of youth who were exposed to different levels of adversity were compared on a standardized peer problem measure and a range of risk measures. Qualitative interviews extended this data and explored vulnerable youth perceptions of social withdrawal as a coping strategy. Results from the survey and qualitative data indicated that a subgroup of youth facing high levels of adversity restricted association with antisocial peers to reduce their behavioural risks. However, without adequate support from adults in both formal support systems and youths' social ecologies to compensate for the loss of peer friendships, this strategy did not reduce behavioural risk in the medium term. The social withdrawal strategy also appeared to heighten mental health concerns for these youth. The implications of this finding for the development of policy and practice with vulnerable youth are discussed.     

Who Is to Blame?

We present the results of a content analysis of communications related to the act of terrorism at Domodedovo airport. They show that mass media plays a significant role as a source of factual, undigested information. The theoretical value of the results is that they show a significant number of cases where an actor is accused with no reference to his actions or nonactions. The range of types of complicity in terrorist activity was substantial.     

Named social workers – better social work for learning disabled people?

In 2016, the Department of Health in England announced that it would pilot the role of Named Social Worker. We chose to be part of the pilot because we regularly witness too many people’s lives being defined by restrictions imposed by professionals. Erroneous associations between the concepts of risk and danger have become the norm in how learning disabled people’s decision-making is perceived and managed. However, we believe social workers educated in the social model of disability and grounded more generally in disability studies offer an alternative perspective. The pilot is an opportunity to test our hypothesis that social work practice rooted in social model thinking can successfully challenge oppressive practice and disabling barriers, thus providing the opportunity for social workers to genuinely be ‘servants not masters’ in the lives of disabled people.     

Keep the hope alive: young Indonesian musicians’ views of the future

Using ethnographic and interview data, this article explores hopes for the future of young Indonesian musicians. The young people are seen to consider their future trajectories in multiple, hierarchical music fields. The article also takes into account the ontological insecurity of jobs as a professional musician, arguing that there is continuous reproduction of a doxa, namely ‘survival of the fittest’ in Indonesia. Yet despite abundant risks to livelihoods, young Indonesian musicians expressed optimistic views about the future. The analysis of data below bridges the gap between the traditionally separate youth studies fields of youth transitions and youth cultures. Our interpretation critically contextualises the dialogue between these two fields based on the experiences of young Indonesian musicians as a part of the Global South.