Probabilistic models over strings have played a key role in developing methods that take into consideration indels as phylogenetically informative events. There is an extensive literature on using automata and transducers on phylogenies to do inference on these probabilistic models, in which an important theoretical question is the complexity of computing the normalization of a class of string-...

BACKGROUND Self-perception of uselessness is associated with increased mortality risk in older adults. However, it is unknown whether and to what extent changes in perceived uselessness are associated with mortality risk. METHODS Using four waves of national longitudinal data of older adults from China (2005, 2008, 2011, and 2014), this study examines the association between changes in percei...

BACKGROUND The association between social relationships and lower mortality has been well documented in Western countries. This study aims to investigate that association among elderly Japanese in a rural area. METHODS An analysis was conducted with 1,994 subjects (58.1% women), 78.3% of the total elderly aged 65 and older in a town, who were independent in activities of daily living. A basel...

BACKGROUND Whether depression is a long-term risk factor for dementia or represents a dementia prodrome is unclear. Therefore, we examined the relationship between depressive symptoms and dementia during short and long follow-up in a population-based cohort. METHODS In the Rotterdam Study, 4393 nondemented individuals were followed for incident dementia for 13.7 years by continuous monitoring...

Self-rated health (SRH) is widely used to capture racial and ethnic disparities in health. It is therefore critical to understand whether individuals with different racial and ethnic backgrounds assess their SRH differently. Despite the high overall predictive validity of SRH for subsequent mortality, few studies paid attention to potential variations by race and ethnicity. This study examines ...

The frailty model, an extension of the proportional hazards model, is often used to model clustered survival data. However, some extension of the ordinary frailty model is required when there exist competing risks within a cluster. Under competing risks, the underlying processes affecting the events of interest and competing events could be different but correlated. In this paper, the hierarchi...

Nearly all tractor PTO arrangements used today consist of a rotating mechanical shaft with two or more universal joints and splined couplings. Although this method of power transfer has been the standard for decades, it continues to be a hazard to farm workers. Commonly, PTO accidents involve the snagging of clothes, resulting in the victim being rapidly and violently drawn into (and around) th...

In this paper, the differences between two variations of proportional representation (PR), open-list PR and closed-list PR, are analyzed in terms of their ability to accurately reflect voter preference. The single nontransferable vote (SNTV) is also included in the comparison as a benchmark. We construct a model of voting equilibria with a candidate who is least preferred by voters in the sense...

Long-term absenteeism due to sickness has been increasing in the past two decades. This has raised many questions about causes, financing, and policy measures to prevent further increases. Answering these questions is even more important in a society with an aging population, which is expected to record even more cases. With data from the Swedish National Insurance Board, proportional hazards m...

Choose the Cox proportional hazards regression model if the values in your dependent variable are duration observations. The advantage of the semi-parametric Cox proportional hazards model over fully parametric models such as the exponential or Weibull models is that it makes no assumptions about the shape of the baseline hazard. The model only requires the proportional hazards assumption that ...