A martingale residual diagnostic for longitudinal and recurrent event data

One method of assessing the fit of an event history model is to plot the empirical standard deviation of standardised martingale residuals. We develop an alternative procedure which is valid also in the presence of measurement error and applicable to both longitudinal and recurrent event data. Since the covariance between martingale residuals at times t ₀ and t > t ₀ is independent of t, a plot of these covariances should, for fixed t ₀, have no time trend. A test statistic is developed from the increments in the estimated covariances, and we investigate its properties under various types of model misspecification. Applications of the approach are presented using two Brazilian studies measuring daily prevalence and incidence of infant diarrhoea and a longitudinal study into treatment of schizophrenia.     

An individual measure of relative survival

Summary.  Relative survival techniques are used to compare survival experience in a study cohort with that expected if background population rates apply. The techniques are especially useful when cause-specific death information is not accurate or not available as they provide a measure of excess mortality in a group of patients with a certain disease. Whereas these methods are based on group comparisons, we present here a transformation approach which instead gives for each individual an outcome measure relative to the appropriate background population. The new outcome measure is easily interpreted and can be analysed by using standard survival analysis techniques. It provides additional information on relative survival and gives new options in regression analysis. For example, one can estimate the proportion of patients who survived longer than a given percentile of the respective general population or compare survival experience of individuals while accounting for the population differences. The regression models for the new outcome measure are different from existing models, thus providing new possibilities in analysing relative survival data. One distinctive feature of our approach is that we adjust for expected survival before modelling. The paper is motivated by a study into the survival of patients after acute myocardial infarction.     

语义化的英语语气系统网络(Ⅰ)

文章有两个目的,其一是为中国学者介绍经过语义化的英语语气系统网络,其二是说明以新的语气系统网络替代之前旧的语气系统网络的重要性。文章的前半部分,即一至四章,通过介绍本文的研究方向,回答关于语气系统的三个问题,回顾早期对语气系统的语义化描述,并阐释影响语气系统语义化进程的因素,从而说明第二个目的。第一个目的由较长的第五章实现,它和附录一起构成了文章的后半部分,着重呈现了一个全新的经过语义化的语气系统网络。      

When Futures Meet the Present

In this essay, I respond to Mische's work on projection and the research of future action. Further, I suggest a tri-partite framework of mechanisms—one I have termed political semiosis—that allows historical actors to materially and figuratively reorient and realign the past, present, and future in projects of transformation.     

Near‐Misses and Future Disaster Preparedness

Disasters garner attention when they occur, and organizations commonly extract valuable lessons from visible failures, adopting new behaviors in response. For example, the United States saw numerous security policy changes following the September 11 terrorist attacks and emergency management and shelter policy changes following Hurricane Katrina. But what about those events that occur that fall short of disaster? Research that examines prior hazard experience shows that this experience can be a mixed blessing. Prior experience can stimulate protective measures, but sometimes prior experience can deceive people into feeling an unwarranted sense of safety. This research focuses on how people interpret near‐miss experiences. We demonstrate that when near‐misses are interpreted as disasters that did not occur and thus provide the perception that the system is resilient to the hazard, people illegitimately underestimate the danger of subsequent hazardous situations and make riskier decisions. On the other hand, if near‐misses can be recognized and interpreted as disasters that almost happened and thus provide the perception that the system is vulnerable to the hazard, this will counter the basic “near‐miss” effect and encourage mitigation. In this article, we use these distinctions between resilient and vulnerable near‐misses to examine how people come to define an event as either a resilient or vulnerable near‐miss, as well as how this interpretation influences their perceptions of risk and their future preparedness behavior. Our contribution is in highlighting the critical role that people's interpretation of the prior experience has on their subsequent behavior and in measuring what shapes this interpretation.     

The effectiveness of job specific training on the occupational performance of student nurses

Body mechanic checklist scores during a one-person pivot transfer, and boosting up in bed were evaluated to determine the effectiveness of training on the work performance of female student nurses from a local college. Thirty subjects participated in the study and were divided into a control group, an experimental group that received basic body mechanic training, and an experimental group that received job specific training. A one-way ANCOVA was calculated to examine the effects of the experimental procedures on the subjects' performance. This revealed a statistically significant difference between the groups (patient transfer F = 10.11, p value < 0.001; boosting F = 38.62, p value < 0.001). A post hoc analysis (Bonferroni procedure) indicated that the job specific training group (mean 11.65, SD 0.66) demonstrated a statistically significant improvement in their performance compared to the other two groups (control group mean 7.5, SD 0.67; BBMT mean 9.66, SD 0.67).     

Revisiting the relationships among gender,marital status,and mental health

Three decades ago, Grove introduced his sex-role theory of mental illness, which attributes women's higher rates of psychological distress to their roles in society. Central to his hypothesis is that marriage is emotionally advantageous for men and disadvantageous for women. This article revisits this topic with data from the National Survey of Families and Households. The analyses indicate that the emotional benefits of marriage apply equally to men and women, but that men and women respond to marital transitions with different types of emotional problems. The implications of these findings for future research on gender and mental health are discussed.     

Accommodating diverse clients' needs in evaluation capacity building: A case study of the Tobacco Control Evaluation Center

In this case study, we detail and analyze how the Tobacco Control Evaluation Center (TCEC), an evaluation technical assistance center that serves approximately 100 local tobacco control organizations in California, endeavors to build capacity among the state-funded local providers it serves by using evaluation capacity building activities with an utilization-focused evaluation framework. We call this a "blended approach" and describe these methods. Satisfaction and demand for TCEC services are documented to provide measurements for evaluation capacity building. Final evaluation report scores from two intervention cycles (2004-2007 and 2007-2010) submitted to the California Health Department, Tobacco Control Division are also assessed and compared. These measures demonstrate an increase in evaluation capacity by local projects under TCEC's purview.     

Shrinkage confidence intervals for the normal mean: Using a guess for greater efficiency

If the unknown mean of a univariate population is sufficiently close to the value of an initial guess then an appropriate shrinkage estimator has smaller average squared error than the sample mean. This principle has been known for some time, but it does not appear to have found extension to problems of interval estimation. The author presents valid two‐sided 95% and 99% “shrinkage” confidence intervals for the mean of a normal distribution. These intervals are narrower than the usual interval based on the Student distribution when the population mean lies in such an “effective interval.” A reduction of 20% in the mean width of the interval is possible when the population mean is sufficiently close to the value of the guess. The author also describes a modification to existing shrinkage point estimators of the general univariate mean that enables the effective interval to be enlarged.