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51.
二维GPSJ分布类及其在保险中的应用   总被引:1,自引:2,他引:1  
本文给出的二维GPSJ分布类(即GPSJ2)在保险领域应用范围较广,如由机动车辆保险由财产损失索赔次数和人身伤亡索赔次数所组成的模型、超额再保险中的由自留保单数和分出报单数所组成的二维模型等。本文在GPSJ1类基础上研究二维GPSJ类,本文给出了此分布类的定义、背景意义、概率计算的递推公式,同时还对各参数的最大似然估计值的求解过程进行了分析。本文最后将这一模型应用于一组机动车辆赔付次数数据,考虑了由财产损失索赔次数、人身伤亡索赔次数组成的二维模型,拟合效果令人满意。  相似文献   
52.
县级政府、供应链管理与农产品上行关系研究   总被引:1,自引:0,他引:1  
基于中国13省87个电子商务进农村示范县的调研材料,分析政府项目驱动下农产品上行问题。实践表明,政策利好为县域农产品电商发展提供了试错空间,“S2B2C”的供应链管理模式对农产品上行的推动作用明显。但是,多数县级政府未能认识到供应链管理之于农产品上行的作用,普遍存在政府治理方式滞后、公共服务网络不健全、农产品区域公用品牌缺乏、冷链等基础设施投入不足等问题。因此,为有效推动农产品上行,政府应进一步推动“公私合作”、构建一体化的公共服务、注重品牌营销、优化产品供应链管理。  相似文献   
53.
Factitious Disorder Imposed by Another (FDIA) can be difficult to expeditiously identify. Understanding personality characteristics of FDIA perpetrators via psychological assessment may decrease the time between initial abuse and identification of FDIA. Personality characteristics of FDIA mother-perpetrators were examined through a comparative analysis of MMPI-2 profiles. It was predicted that mother-perpetrators would have significantly higher overall profile elevations on the MMPI-2 and elevations on specific clinical scales than a comparative control group. Results indicated that mother-perpetrators displayed significantly higher, elevations on the Psychasthenia (Pt) and Schizophrenia (Sc) scales and a trend toward significantly higher elevation on the Psychopathic Deviate (Pd) scale than the control group. These findings, along with the demographic information obtained, establish a preliminary foundation for understanding an overall profile of mother-perpetrators.  相似文献   
54.
In this article, we study global L2 error of non linear wavelet estimator of density in the Besov space Bspq for missing data model when covariables are present and prove that the estimator can achieve the optimal rate of convergence, which is similar to the result studied by Donoho et al. (1996) Donoho, D.L., Johnstone, I.M., Kerkyacharian, G., Picard, D. (1996). Density estimation by wavelet thresholding. Ann. Stat. 24:508539.[Crossref], [Web of Science ®] [Google Scholar] in complete independent data case with term-by-term thresholding of the empirical wavelet coefficients. Finite-sample behavior of the proposed estimator is explored via simulations.  相似文献   
55.
The aim of this study is to measure and describe symptoms of eating disorders among females in treatment for drug addiction in Norway. Previous clinical and epidemiological studies have revealed coprevalence between eating disorders and substance use or abuse. However, few studies have measured eating disorders in drug-using samples and even fewer within the context of drug treatment. In this study, 29 females with drug use disorder in residential treatment were tested with the Eating Disorder Inventory–2. A subgroup of 9 females (31%) with significant symptoms of eating disorders was identified. The characteristics of this group and possible clinical consequences are discussed.  相似文献   
56.
冯博  叶绮文  陈冬宇 《管理科学》2017,20(4):113-126
P2P ( 个人对个人) 网络借贷是指通过网络借贷平台,在全球范围内实现个人与个人或小微企业间的小额信用借贷交易. P2P 网络借贷作为全新的互联网金融服务受到商业界的高度关注,而且发展成为学术研究的国际前沿领域. 对 P2P 网络借贷相关研究文献进行了综述,具体从影响借贷交易的信息因素、羊群效应以及社交网络等 3 个方面分析了该领域研究的现状和发展脉络. 因为中国已超越美国成为全球最大的 P2P 网络借贷交易市场,所以结合中国的具体情境和问题,提出了未来研究工作的展望.  相似文献   
57.
58.
BackgroundIn the Palestinian community, lifestyle changes, rapid urbanization and socioeconomic development, stress, smoking, and changes in food habits has increased the risk of non-communicable diseases especially diabetes mellitus. Diabetes complications can be prevented if the glycemic status of patients with diabetes is maintained within a nearly normal range. Therefore, patient education is critical in controlling blood glucose levels within the normal range.ObjectiveThis study aimed at measuring the effect of diabetes educational intervention program for patients suffering from type 2 diabetes attending the Diabetes Clinic in Tulkarim Directorate of Health.MethodsA short duration observational study involving pre- and post-test educational intervention program was carried out on a relatively small number of type 2 diabetes patients at the Diabetes Clinic in Tulkarim Directorate of Health. In total, 215 patients attended a group-based 4 h educational intervention session about diabetes. The program included explaining diabetes mellitus-symptoms, risk factors, types, treatment and complications and main aspects of self-care of the disease (foot care, eye care, and blood glucose monitoring), main aspects of dietary management, weight reduction, blood pressure, smoking cessation, periodic investigations, home monitoring and importance of physical activity. Knowledge evaluation questionnaire were evaluated pre- and post-study. Anthropometric measurements such as body weight (WT), body mass index (BMI) and laboratory tests such as fasting blood glucose (FBG), hemoglobin A1C (HbA1c), cholesterol (Chol), and triglycerides (TG) were measured both at the beginning and at the end of the study. Significance of the results was assessed by paired t-test at 95% confidence interval.ResultsThe participant’s mean age was 51.07 that ranged between 31 and 70 years. For a total of 215 participants, 41.4% were males and 58.6% were females. The mean weight before educational intervention was 80.81 ± 14.95 kg (82.6 kg for males and 79.5 kg for females) that decreased to 78.9 ± 14.33 kg (81.1 kg for males and 77.3 kg for females) after educational intervention program. The BMI also decreased significantly after educational intervention. The mean fasting blood sugar was 188.65 ± 71.45 mg/dL before educational intervention that decreased to 177.7 ± 66.11 mg/dL after the educational intervention (p = 0.049). The mean glycosylated hemoglobin was 8.57 ± 1.21 before educational intervention that decreased to 7.95 ± 1.42 after educational intervention. The mean value of cholesterol before educational intervention was 183.27 ± 37.74 mg/dL that decreased to 169.57 ± 34.23 mg/dL after educational intervention. The mean triglycerides value decreased after educational intervention from 209.85 ± 171.04 mg/dL to 183.28 ± 152.4 mg/dL (p = 0.025). The mean score of knowledge questionnaire before educational intervention was 60.6 ± 20.65 that increased to 78.1 ± 13.4 after conducting educational intervention.ConclusionsDiabetes education was found to be effective on BMI, FBG, HbA1c, Chol, TG, and knowledge.RecommendationsDiabetes education is a cornerstone in the management and care of diabetes and should be an integral part of health planning involving patient’s family, diabetes care team, community, and decision makers in the education process.  相似文献   
59.
The benchmark dose (BMD) approach has gained acceptance as a valuable risk assessment tool, but risk assessors still face significant challenges associated with selecting an appropriate BMD/BMDL estimate from the results of a set of acceptable dose‐response models. Current approaches do not explicitly address model uncertainty, and there is an existing need to more fully inform health risk assessors in this regard. In this study, a Bayesian model averaging (BMA) BMD estimation method taking model uncertainty into account is proposed as an alternative to current BMD estimation approaches for continuous data. Using the “hybrid” method proposed by Crump, two strategies of BMA, including both “maximum likelihood estimation based” and “Markov Chain Monte Carlo based” methods, are first applied as a demonstration to calculate model averaged BMD estimates from real continuous dose‐response data. The outcomes from the example data sets examined suggest that the BMA BMD estimates have higher reliability than the estimates from the individual models with highest posterior weight in terms of higher BMDL and smaller 90th percentile intervals. In addition, a simulation study is performed to evaluate the accuracy of the BMA BMD estimator. The results from the simulation study recommend that the BMA BMD estimates have smaller bias than the BMDs selected using other criteria. To further validate the BMA method, some technical issues, including the selection of models and the use of bootstrap methods for BMDL derivation, need further investigation over a more extensive, representative set of dose‐response data.  相似文献   
60.
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