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941.
Adriano K. Suzuki Gladys D. C. Barriga Francisco Louzada Vicente G. Cancho 《统计学通讯:理论与方法》2017,46(6):3080-3098
In this paper we propose a general cure rate aging model. Our approach enables different underlying activation mechanisms which lead to the event of interest. The number of competing causes of the event of interest is assumed to follow a logarithmic distribution. The model is parameterized in terms of the cured fraction which is then linked to covariates. We explore the use of Markov chain Monte Carlo methods to develop a Bayesian analysis for the proposed model. Moreover, some discussions on the model selection to compare the fitted models are given, as well as case deletion influence diagnostics are developed for the joint posterior distribution based on the ψ-divergence, which has several divergence measures as particular cases, such as the Kullback–Leibler (K-L), J-distance, L1 norm, and χ2-square divergence measures. Simulation studies are performed and experimental results are illustrated based on a real malignant melanoma data. 相似文献
942.
This study proposes a synthetic double sampling s chart that integrates the double sampling (DS) s chart and the conforming run length chart. An optimization procedure is proposed to compute the optimal parameters of the synthetic DS s chart. The performance of the synthetic DS s chart is compared with other existing control charts for monitoring process standard deviation. The results show that the synthetic DS s chart is more effective for detecting increases in the process standard deviation for a wide range of shifts. An example is provided to illustrate the operation procedure of the synthetic DS s chart. 相似文献
943.
Here we consider an exponentiated version of the reduced Kies distribution and discuss some of its properties. The parameters of the distribution are estimated by the method of maximum likelihood and illustrated with the help of certain real-life data sets. Asymptotic behavior of the maximum likelihood estimators of the parameters of the distribution is also studied by using certain simulated data sets. 相似文献
944.
Weighted distributions (univariate and bivariate) have received widespread attention over the last two decades because of their flexibility for analyzing skewed data. In this article, we propose an alternative method to construct a new family of bivariate and multivariate weighted distributions. For illustrative purposes, some examples of the proposed method are presented. Several structural properties of the bivariate weighted distributions including marginal distributions together with distributions of the minimum and maximum, evaluation of the reliability parameter, and verification of total positivity of order two are also presented. In addition, we provide some multivariate extensions of the proposed models. A real-life data set is used to show the applicability of these bivariate weighted distributions. 相似文献
945.
In this article we discuss various strategies for constructing bivariate Kumaraswamy distributions. As alternatives to the Nadarajah et al. (2011) bivariate model, four different models are introduced utilizing a conditional specification approach, a conditional survival function approach, and an Arnold–Ng bivariate beta distribution construction approach. Distributional properties for such bivariate distributions are investigated. Parameter estimation strategies for the models are discussed, as are the consequences of fitting two of the models to a particular data set involving the proportion of foggy days at two different airports in Colombia. 相似文献
946.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting. 相似文献
947.
The paper entitled “Bivariate and Multivariate Normal Characterizations: A Brief Survey,” by Hamedani, which was published in 1992, covered the published characterizations of bivariate and multivariate normal (MVN) distributions from 1941 to 1991. The present work is a follow-up to the 1991/1992 survey which includes not only characterizations of the bivariate and MVN distributions, but also characterizations of the matrix variate normal distribution, which have appeared from 1991/1992 to the present. 相似文献
948.
It's About Time! Examining Received Dosage and Program Duration as Predictors of Change Among Non‐Distressed and Distressed Married Couple and Relationship Education Participants 下载免费PDF全文
Angela B. Bradford Lauren Drean Francesca Adler‐Baeder Scott A. Ketring Thomas A. Smith 《Journal of marital and family therapy》2017,43(3):391-409
Although Couple and Relationship Education (CRE) programs were intended to be preventive in nature, an emerging reality is that relationally distressed couples are attending programs. This has raised questions about both its general usefulness and what is known regarding predictors of change in CRE for distressed couples particularly. Previous work has identified dosage and duration as important moderators of changes, and there are myriad program contexts offered, highlighting the need to examine these among distressed couples. This study utilized a sample of community CRE participants and examined received dosage and program duration as predictors of change. Comparing results for distressed and non‐distressed participants, we found several group differences. Findings suggest that it is important to consider distress level and time spent in programs when placing participants. In addition, research should continue to examine these groups separately (or comparatively) to find out what works for whom. 相似文献
949.
Arthur C. Nielsen 《Journal of marital and family therapy》2017,43(4):685-699
This essay reviews the most significant contributions of psychodynamic thought to the field of couple therapy. It distills the work of numerous clinicians and researchers who, though writing from diverse perspectives, share fundamental assumptions and concerns. Rather than emphasizing differences between schools of thought, this paper mines their best contributions in a discussion of five central therapeutic targets: underlying issues, divergent subjective experiences, transferences, projective identification, and acceptance. Two detailed cases illustrate the benefits and techniques for targeting these five therapeutic domains. Video Abstract is found in the online version of the article . 相似文献
950.