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31.
This article is concerned with the comparison of P-value and Bayesian measure in point null hypothesis for the variance of Normal distribution with unknown mean. First, using fixed prior for test parameter, the posterior probability is obtained and compared with the P-value when an appropriate prior is used for the mean parameter. In the second, lower bounds of the posterior probability of H0 under a reasonable class of prior are compared with the P-value. It has been shown that even in the presence of nuisance parameters, these two approaches can lead to different results in the statistical inference.  相似文献   
32.
In this cross-sectional study, we tested the relationship between sociophysical environment, quality of life (QOL), and perceived social support among elderly in Iran. The sample includes 128 participants recruited in the city of Shahrekord, Iran. We measured Evaluation of Older People Living Environment (EVOLVE); Control, Autonomy, Self-realization and Pleasure scale (CASP-19) and Multidimensional Scale of Perceived Social Support (MSPSS) tools respectively, through home-based observation and interview. A significant relationship was found between several domains of home environment, QOL, and perceived social support. The interaction effect of the home environment and gender in relation to QOL and perceived social support was statistically significant. Our results support that the home physical environment may not be considered a strong predictor of QOL among the Iranian elderly.  相似文献   
33.

Background

During the last decades, there has been an alarming and dramatic increase in the number of cesarean births in both developed and undeveloped countries. This increase has not been clinically justified but, nevertheless, has raised an important number of issues.

Aim

The aim of this study was to determine the risk factors associated with the high cesarean section rates in Lebanon.

Methods

This study is based on a sample of 29,270 Lebanese women who were pregnant between 2000 and 2015. Among these, 14,327 gave birth by cesarean section and 14,943 gave birth vaginally. To identify the risk factors of cesarean section, logistic regression was applied as a statistical method using the SPSS statistical package.

Findings

Of the 29,270 pregnant women included in the study, 49% had cesarean sections while 51% gave birth vaginally. Repeat cesarean section accounted for 23% while vaginal birth after cesarean accounted for only 0.2% of deliveries. In addition, weekdays were associated with a preference of providers to carry out more cesarean sections. According to an analysis of our data using logistic regression, the risk factors associated with the increase in cesarean section rates were advanced maternal age, elective cesarean section, malpresentation of fetus, multiple birth, prolonged pregnancy, prolonged labor, and fetal distress.

Conclusion

Based on these results, it is recommended that a new health policy be implemented to reduce the number of unnecessary cesarean deliveries in Lebanon.  相似文献   
34.
Although the organizational structures and operating procedures of state substance abuse prevention systems vary substantially across states, there is scant empirical research regarding approaches for rigorous assessment of system attributes and which attributes are most conducive to overall effectiveness. As one component of the national cross-site evaluation of the SPF State Incentive Grant Program (SPF SIG), an instrument was developed to assess state substance abuse prevention system infrastructure in order to measure infrastructure change and examine the role of state infrastructure in achieving prevention-related outcomes. In this paper we describe the development of this instrument and summarize findings from its baseline administration. As expected, states and territories were found to vary substantially with respect seven key characteristics, or domains, of state prevention infrastructure. Across the six domains that were assessed using numeric ratings, states scored highest on data systems and lowest on strategic planning. Positive intercorrelations were observed among these domains, indicating that states with high capacity on one domain generally have relatively high capacity on other domains as well. The findings also suggest that state prevention infrastructure development is linked to both funding from state government and the presence of a state interagency coordinating body with decision-making authority. The methodology and baseline findings presented will be used to inform the ongoing national cross-site evaluation of the SPF SIG and may provide useful information to guide further research on state substance abuse prevention infrastructure.  相似文献   
35.
36.
Reconstructions and projections of populations by age, sex, and educational attainment for 120 countries since 1970 are used to assess the global relationship between improvements in human capital and democracy. Democracy is measured by the Freedom House indicator of political rights. Similar to an earlier study on the effects of improving educational attainment on economic growth, the greater age detail of this new dataset resolves earlier ambiguities about the effect of improving education as assessed using a global set of national time series. The results show consistently strong effects of improving overall levels of educational attainment, of a narrowing gender gap in education, and of fertility declines and the subsequent changes in age structure on improvements in the democracy indicator. This global relationship is then applied to the Islamic Republic of Iran. Over the past two decades Iran has experienced the world's most rapid fertility decline associated with massive increases in female education. The results show that based on the experience of 120 countries since 1970, Iran has a high chance of significant movement toward more democracy over the following two decades.  相似文献   
37.
Abstract

This paper proposes a new mathematical model for the reliability-redundancy allocation problem (RRAP) with a choice of redundancy strategies. To maximize the reliability of a system, this model chooses the best redundancy strategy from among both active and standby ones for each subsystem. For those with a standby strategy, a continuous time Markov chain model is used to calculate the exact reliability values. In order to solve the proposed mixed-integer non-linear programing model, a powerful evolutionary algorithm, called water cycle algorithm (WCA), is developed and implemented on three famous benchmark problems. Finally, the results of different benchmark problems are compared with those previously reported to show the superiority of the proposed model and the efficiency of WCA.  相似文献   
38.
This research proposes a multi-criteria decision-making (MCDM) framework and demonstrates the impact of competitive conditions on supplier evaluation process for construction supply chains. The paper focuses on the supply chain of a large-scale housing project in order to illustrate the role of competitive capability and suppliers’ profile and its influence on supplier evaluation based on prevailing supply/market conditions. Various scenarios are investigated to demonstrate the impact of competition on supplier evaluation. The contribution of the study lies in highlighting the impact of supply/market conditions on MCDM decisions causing supplier evaluation ‘imbalance’ and MCDM usage. It is expected that the study will be useful for project management, construction, supply chain management, sourcing professionals. The findings of the study are generalisable to projects-based situations such as petroleum refinery and ship building where bill of materials typically consists of thousands of items and a large number of suppliers are involved.  相似文献   
39.
This study proposes and follows a specific and systematic framework for implementing Lean Six Sigma (LSS) methodology in a telecom company in order to improve customer satisfaction by minimizing the company’s response time to customer requirements. The goal of this study was achieved by utilizing several LSS tools under five phases of the DMAIC methodology. Unlike previous studies in the telecom sector that used only qualitative method, in this study, both qualitative and quantitative methods were utilized to draw meaningful conclusions. As a result of the implementation of the LSS methodology, the average order fulfilment lead time for sales orders (SO) and value-added service (VAS) orders was reduced from 10.3 to 5.9 days and from 1.5 to 0.5 days, respectively. The reduction in lead time resulted in an increase in the sigma level for SO and VAS orders from 0.44 to 1.26 and from 0.73 to 2.66, respectively. These improvements were expected to lead to a financial benefit in savings of over $600,000 per year in operational costs, enhancements to customer experience and an increase in revenue generating opportunities. Moreover, this article enriches the existing literature on the application of LSS concept in the service industry, and helps the company to speed up the response to customer requirements.  相似文献   
40.
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