Extended scaled prediction variance optimality for modified central composite design

Robust parameter designs (RPDs) enable the experimenter to discover how to modify the design of the product to minimize the effect due to variation from noise sources. The aim of this article is to show how this amount of work can be reduced under modified central composite design (MCCD). We propose a measure of extended scaled prediction variance (ESPV) for evaluation of RPDs on MCCD. Using these measures, we show that we can check the error or bias associated with estimating the model parameters and suggest the values of α recommended for MCCS under minimum ESPV.     

How Are Money Worries Affecting Middle-Aged,Young-Old,and Old–Old People’s Perceived Couple Relationship?

While the association between financial strain and couple interaction has been well-established in the literature on economic stress, little research has investigated the association among middle-aged and older populations. The present study examined the relationships between financial strain and couple functioning of middle-aged, young-old, and old–old people using the 2010 Health and Retirement Study. Findings show that subjective financial strain was positively associated with partner undermining and negatively with partner support, controlling for the effects of objective financial situations among middle-aged, young-old, and old–old couples. There were gender and age differences in the interaction effects of financial strain and financial control on couple functioning. For middle-aged men, financial control may have different associations with couple behaviors depending on the level of financial strain. When the level of financial strain is high, the positive effect of financial control disappears and the effect changes even in a negative way. Findings provide suggestions for practitioners and researchers.     

Semiparametric transformation models for multivariate panel count data with dependent observation process

This article discusses regression analysis of multivariate panel count data in which the observation process may contain relevant information about or be related to the underlying recurrent event processes of interest. Such data occur if a recurrent event study involves several related types of recurrent events and the observation scheme or process may be subject-specific. For the problem, a class of semiparametric transformation models is presented, which provides a great flexibility for modelling the effects of covariates on the recurrent event processes. For estimation of regression parameters, an estimating equation-based inference procedure is developed and the asymptotic properties of the resulting estimates are established. Also the proposed approach is evaluated by simulation studies and applied to the data arising from a skin cancer chemoprevention trial.     

The Representation of Hypergeometric Random Variables using Independent Bernoulli Random Variables

In this paper, we show that a hypergeometric random variable can be represented as a sum of independent Bernoulli random variables that are, except in degenerate cases, not identically distributed. In the proof, we use the factorial moment generating function. An asymptotic result on the probabilities of the Bernoulli random variables in the sum is also presented. Numerical examples are used to illustrate the results.     

Designs for estimating the difference between two responses

In this paper the problem of designing experiments for estimating the difference between responses at two arbitrary points in the region of interest is considered. Under the average mean squared error criterion the design moment conditions have been worked out. The results have been applied to the class of central composite designs.     

Acculturative Stress and Mental Health Among Korean Adolescents in the United States

This study investigated Korean-American adolescents' stress related to their acculturation experiences and mental health. A total of 260 Korean-American adolescents from immigrant families (ages 12–18 years) participated in the study. The U.S. born group had a higher level of acculturative stress than the Korea-born group (t = 2.222; df = 258; p < .05). Males reported a higher level of self-esteem than females (t = ?2.112; df = 257; p < .05). Acculturative stress was positively correlated with depression (r = .299; p < .01) and negatively related to self-esteem (r = ?.292; p < .01). Self-esteem was negatively related to depression (r = ?.536; p < .01).     

Coffee intake,health-related quality of life,and associated factors of overactive bladder in older Korean women living in rural South Korea

ABSTRACT

Overactive bladder (OAB) is a common health problem in older women. The aim of the study was to investigate coffee consumption, health-related quality of life (HRQOL), and associated factors of OAB in older Korean women living in rural South Korea. A total of 248 women aged 65 years and older participated in this study. Chi-square tests, t-tests, and multivariable logistic regressions were performed. The means of coffee consumption between OAB and non-OAB groups were not significantly different. Women with OAB showed significantly lower HRQOL than women with stress urinary incontinence only. OAB was associated with high body mass index and poor health status.     

Linear filter model representations for integrated process control with repeated adjustments and monitoring

An integrated process control (IPC) procedure is a scheme which combines the engineering process control (EPC) and the statistical process control (SPC) procedures for the process where the noise and a special cause are present. The most efficient way of reducing the effect of the noise is to adjust the process by its forecast, which is done by the EPC procedure. The special cause, which produces significant deviations of the process level from the target, can be detected by the monitoring scheme, which is done by the SPC procedure. The effects of special causes can be eliminated by a rectifying action. The performance of the IPC procedure is evaluated in terms of the average run length (ARL) or the expected cost per unit time (ECU). In designing the IPC procedure for practical use, it is essential to derive its properties constituting the ARL or ECU based on the proposed process model. The process is usually assumed as it starts only with noise, and special causes occur at random times afterwards. The special cause is assumed to change the mean as well as all the parameters of the in-control model. The linear filter models for the process level as well as the controller and the observed deviations for the IPC procedure are developed here.