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By considering uncertainty in the attributes common methods cannot be applicable in data clustering. In the recent years, many researches have been done by considering fuzzy concepts to interpolate the uncertainty. But when data elements attributes have probabilistic distributions, the uncertainty cannot be interpreted by fuzzy theory. In this article, a new concept for clustering of elements with predefined probabilistic distributions for their attributes has been proposed, so each observation will be as a member of a cluster with special probability. Two metaheuristic algorithms have been applied to deal with the problem. Squared Euclidean distance type has been considered to calculate the similarity of data elements to cluster centers. The sensitivity analysis shows that the proposed approach will converge to the classic approaches results when the variance of each point tends to be zero. Moreover, numerical analysis confirms that the proposed approach is efficient in clustering of probabilistic data.  相似文献   
23.
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   
24.
In this study, we propose an information measure of uncertainty associated with the random equilibrium residual lifetime of a system driven by N-State Random Evolution. A U-statistic test driven by a moment inequality is proposed for testing the hypothesis that the uncertainty of equilibrium remaining life of a system remains unchanged (when system is in the steady state) against the alternative situation when system’s equilibrium residual life has increasing uncertainty over time (i.e., the life distribution has Increasing Equilibrium Residual Entropy property). Some numerical results such as tabulated critical values and empirical power of the proposed test statistic are presented as well.  相似文献   
25.

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   
26.
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   
27.
Maqasid of Shari'ah is a millennium old theory on the higher objectives of Islamic divine law. As the discipline of Islamic economics and finance grew in politico-economic importance in the past three decades, a cathartic trend has emerged among Muslim experts to realign economic and financial practices with not merely the minimum legal requirements of religion but also the wisdom and crucial objectives of Shari'ah. An expositive example of this is the monetary economics debate of a Shari'ah consonant currency. Though vast majority of religious clerics have approbated fiat and paper currencies in strict legal terms since the 1980s, a revisionist movement since the mid-1990s seeks to counter it—some going as far as indorsing reversion to gold and silver coinage of medieval Islamic epoch of affluence. Unlike orthodox fiqhi (strict jurisprudentialism) approach that involves legalese with little leeway, Maqasid approach concerns itself with the spirit of the law. This paper operates in the exciting laboratory of Maqasidic framework to appraise the multitudinous role of fiat currency in protecting economic, political, and social public interests, prevention of harm, promotion of egalitarianism, and attainment of ultimate utopic vision of theological and spiritual demands in Shari'ah. The paper contributes, theoretically, by introducing several moral-philosophical arguments against fiat’s compatibility with Shari'ah, and, practically, by prognosticating the future course of discourse in light of advancements in technological innovations—including nascent crypto-currencies.  相似文献   
28.
This study looks at polarization and its components’ sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period; primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution. Increasing the accounting period confirms the reduction in inequality found for shorter periods, but polarization is virtually unchanged, because income group identification increases. Applying different equivalence scales does not change polarization ranking for different years, but identification ranks are affected. The welfare state considerably reduces income polarization and inequality, but at the expense of some more identification.   相似文献   
29.
Bivariate rank set sample (BVRSS) matched pair sign test is introduced and investigated for different ranking based schemes. We show that this test is asymptotically more efficient and more powerful than its counterpart sign test based on a bivariate simple random sample (BVSRS) for different ranking schemes. The asymptotic null distribution and the efficiency of the test are derived. Pitman’s asymptotic relative efficiency is used to compare the asymptotic performance of the matched pair sign test using BVRSS versus using BVSRS in all ranking cases. For small sample sizes, the bootstrap method is used to estimate P-values. Numerical comparisons are used to gain insight about the efficiency of the BVRSS sign test compared to the BVSRS sign test. Our numerical and theoretical results indicate that using any ranking scheme of BVRSS for the matched pair sign test is more efficient than using BVSRS.  相似文献   
30.
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