Some remarks on the physical models concerning two different approaches to inference in statistical process control

Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.     

试论双回路维稳模型

社会领域也存在某种惯性趋势,即社会趋稳性。这一概念的提出旨在说明,一切不稳定的产生,必定是受到某种作用力的结果。而社会趋稳性与变动力量的结合,便会造成不同程度的反作用力。这种反弹行为在实践中很容易被界定为＂不稳定因素＂。由于维稳的主客体都是人,而＂人是需求动物＂,所以,维稳的具体政策若不能够融入人的思考、理解及感情,将很难实现人际有效的沟通,进而妨碍动态稳定的实现。以组织平衡理论、需求层次理论、安全阀理论及组织学习理论为基础的双回路维稳模型的提出,旨在强调人类需求、基本秩序以及自然法则在维稳中的关键作用。     

Maternal union instability and childhood mortality risk in the Global South, 2010–14

Efforts to improve child survival in lower-income countries typically focus on fundamental factors such as economic resources and infrastructure provision, even though research from post-industrial countries confirms that family instability has important health consequences. We tested the association between maternal union instability and children’s mortality risk in Africa, Latin America and the Caribbean, and Asia using children’s actual experience of mortality (discrete-time probit hazard models) as well as their experience of untreated morbidity (probit regression). Children of divorced/separated mothers experience compromised survival chances, but children of mothers who have never been in a union generally do not. Among children of partnered women, those whose mothers have experienced prior union transitions have a higher mortality risk. Targeting children of mothers who have experienced union instability—regardless of current union status—may augment ongoing efforts to reduce childhood mortality, especially in Africa and Latin America where union transitions are common.     

Relationship Churning and Parenting Stress Among Mothers and Fathers

Researchers have documented the consequences of relationship instability for parenting stress but have given little attention to within‐partner relationship instability. In this study, the authors used data from the Fragile Families and Child Wellbeing Study (N = 3,544) to estimate the association between within‐partner relationship instability (known as churning or on‐again/off‐again relationships) and parenting stress. First, they found that by the focal child's 5th birthday about 16% of biological parents experience churning. Second, compared to being stably together with or stably separated from the child's other parent, churning is associated with greater parenting stress for both mothers and fathers. Because parenting stress is the same or higher among churners compared to their counterparts who stably separate, this suggests that, more than a change in partner, relationship instability—whether within or across relationships—is tied to parenting stress.     

The Great Recession of 2007: An Agenda for Social Justice

The Great Recession, the most severe economic crisis since the Great Depression, officially began in December 2007 with an 8 trillion dollar housing bubble and lasted until June 2009, resulting in loss in consumer spending and collapse in the nation’s business investment. For American workers, the Great Recession had far-reaching implications: unemployment, underemployment, pay cuts, and cutbacks in household spending. Although social work has a historical commitment to address the vulnerabilities of people and communities, we argue that the profession neglected to understand fully the factors associated with the Great Recession and to mount an agenda for justice in response to its worker-related impact.     

The role of eviction in veterans’ homelessness recidivism*

Eviction is one of the leading causes of homelessness in the U.S.A. Though permanent supportive housing (PSH) helps participants maintain housing, some still leave due to eviction. This study aimed to determine whether eviction is an important predictor of recidivism and time to return to homelessness for participants exiting PSH. The characteristics and post-exit service use of 2802 Veteran PSH participants were analyzed based on exit reason. A Cox proportional hazards survival analysis modeled risk factors for returning to homelessness within 360 days of exit. Compared with other exiters, evicted Veterans remained in the program for less time, were less likely to be receiving service-connected compensation, and used more services – particularly mental health and substance use services – following their exit, and those who returned to homelessness did so more quickly. Identifying participants who might benefit from more intensive services, project-based housing, or income supports may prevent evictions and subsequent returns to homelessness.     

Partnership Instability and Child Well‐Being

We use data from three waves of the Fragile Families Study (N= 2,111) to examine the prevalence and effects of mothers’ partnership changes between birth and age 3 on children’s behavior. We find that children born to unmarried and minority parents experience significantly more partnership changes than children born to parents who are married or White. Each transition is associated with a modest increase in behavioral problems, but a significant number of children experience 3 or more transitions. The association between instability and behavior is mediated by maternal stress and lower quality mothering. The findings imply that policies aimed at reducing maternal stress and partnership instability may improve child well‐being.     

Linking Financial Strain to Marital Instability: Examining the Roles of Emotional Distress and Marital Interaction

Using a sample consisting of 4,997 married couples from the National Survey of Families and Households, individual emotional distress, the occurrence of couple disagreements, couple fighting, and couple quality time together mediated the relationship between financial strain and personal assessments of marital instability. The overall results suggest that financial strain influences both positive and negative forms of couple interaction which are stronger mediators than personal emotional distress of the relationship between financial strain and marital instability. The results further suggest that there were no gender differences among these linkages.     

Changes in conjugal life in Canada: Is cohabitation progressively replacing marriage?

This article aims first to contrast the trends of marriage and cohabitation across different regions in Canada, and second, to assess whether cohabitation constitutes a new stage in the progression to marriage, or an alternative to marriage altogether. Based on various empirical demographic indicators, the analysis shows profound differences across the country. In Quebec, cohabiting unions are now widely accepted as forming the basis for family life, whereas they still largely constitute a childless prelude to marriage elsewhere in Canada. The authors discuss the role of different religious and cultural backgrounds, and of recent changes in the relationships between men and women, in accounting for the divergent evolution observed.