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91.
Three forms of a general null hypothesis Ho on the factorial parameters of a general asymmetrical factorial paired comparison experiment are considered. A class of partially balanced designscorresponding to each form of H0 is constructed and the A,D and ioptimal design, minimizing the trace, determinant and largest eigenvalue of a defined covariance matrix of related maximumlikelihoodestimators, in that class is determined. Moreover, the optimal design in each class maximizes the noncentrality parameter λ2 of the asymptotic noncentral chi-square distribution of the likelihood ratiostatistic -2 log λ for testing Ho under defined local alternatives. These results apply directly to symmetrical factorial paired comparison experiments as special casesExamples are given forillustrating applications of the developed results  相似文献   
92.
Nonparametric inference for point processes is discussed by way of histograms, which provide a nice tool for the analysis of on-line data. The construction of histograms depends on a sequence of partitions, which we take tc be nonenibedded to allow partitions with sets of equal measure. This presents some theoretical problems, which are addressed with an assumption on the decomposition of second order moments. In another direction, we drop the usual independence assumption on the sample, replacing it by a strong mixing assumption. Under this setting, we study the convergence of the histogram in probability, which depends on approximation conditions between the distributions of random pairs and the product of their marginal distributions, and^almost completely, which is based on the decomposition of the second order moments. This last convergence is stated on two versions according to the assumption of Laplace transforms or the Cramer moment conditions. These are somewhat stronger, but enable us to recover the usual condition on the decrease rate of sets on each partition. In the final section we prove that the finite dimensional distributions converge in distribution to a Gaussian centered vector with a specified covariance.  相似文献   
93.
Background: Late-onset hypogonadism (LOH) presents with low serum testosterone (TT) levels and sexual and nonsexual symptoms. Erectile dysfunction affects a man’s self-esteem and as a result partner relationship and quality of life.

Objectives: To investigate the andrological clinical profile outcomes of testosterone therapy (TTh) in men (n?=?88) with symptomatic LOH complaints and symptoms.

Main outcome measures: Erectile function was assessed using the International Index of Erectile Function-5 questionnaire at baseline and at 6 and 12 months of TTh. In addition, penile length was measured at baseline and 12 months. We also evaluated nocturnal penile tumescence (NPT, using RigiScan) and blood flow of cavernous arteries (penile Doppler ultrasonography) at baseline and 12 months of TT.

Materials and methods: Eighty-eight LOH men (Mage 51.1 years) with erectile dysfunction, all with serum TT?<10.4?nmol/L before TTh. Patients received intramuscular long-acting testosterone undecanoate for 12 months.

Results: Following TTh, in all patients, serum TT levels were restored within 3 months to normal levels. Compared with baseline values, erectile function significantly improved at 6 (mean score increase 1.95) and 12 months (mean score increase 2.16). No significant changes in penile length were observed. NPT significantly improved at 12 months in terms of both the frequency (mean increase 1.27 times) and duration of rigidity (mean increase 5.12?min). As regards the blood flow of the cavernous arteries, we observed a significant improvement (decrease of 1.16?cm/s) and end diastolic velocity of the penile arteries.

Conclusion: TTh in men with LOH resulted in improvement of the erectile function, NPT, and to some extent the blood flow of the cavernous arteries.  相似文献   
94.
95.
This analysis suggests a theoretical refinement of migrant acculturation theories to deal specifically with refugee acculturation experiences. Using the case of family dynamics among Somali refugees in Minnesota, we find that the same factors that are theorized to affect voluntary migrants are also important for refugees. Specifically, the nature of exit from the sending society, the reception in a new location, and group characteristics all appear to be important. However, within the category of exit from the sending society, there are specific concerns that will be more relevant to refugees than to “voluntary” migrants. Specifically, the ongoing condition of the sending society and the effects of any transitions on transnational ties are critically important in the refugee context. We demonstrate how the societal upheaval that created the Somali refugee community also affected culture and connections within Somalia, and how this has an ongoing impact on the US Somali refugee community. We argue that it is valuable to refine the acculturation framework when considering refugees.  相似文献   
96.
This paper has developed a multidimensional model usable in assessing economic, social, political and cultural dimensions of poverty by utilizing primary data collected from 78 villages in Bangladesh using a participatory approach. Employing the developed model, a comparative analysis has been performed between microfinance-driven government (GO) and NGO (non-government organization) projects to explore their relative effectiveness in enhancing wellbeing of the poor in rural Bangladesh. It is observed that GO agencies are more effective in enhancing ‘economic wellbeing’ of the poor, whereas NGOs are contributing more in the ‘social’ aspects of wellbeing. Findings also revealed that, as whole, GO agencies perform 42% better than NGOs in improving living standards of the rural poor which contradicts with the existing literature of poverty reduction projects in developing countries.  相似文献   
97.
Ahmed S  Mosley WH 《Demography》2002,39(1):75-93
This study examined the relationship between the use of maternal-child health (MCH) care and the use of contraceptives. The high correlation between the two may be due to the independent effect of one on the other or to an association of both with the same or similar background factors. We used structural equation models to examine the relationship between these two interventions. The data were derived from six Demographic and Health Surveys: Zimbabwe from Sub-Saharan Africa, Thailand from Asia, Egypt and Tunisia from North Africa, and Guatemala and Colombia from Latin America. The results show that in all six countries, the use of contraceptives and MCH care are significantly associated, independent of intervening factors; this finding suggests that families develop a joint demand for better-quality health and limited family size and translate these demands into action by using health services for mothers and for children and by voluntarily regulating fertility.  相似文献   
98.
Bangladesh     
In Bangladesh the Population Control and Family Planning Division of the Ministry of Health and Population Control has decided to delegate increased financial and administrative powers to the officers of the family planning program at the district level and below. Currently, about 20,000 family planning workers and officials are at work in rural areas. The government believes that the success of the entire family planning program depends on the performance of workers in rural areas, because that is where about 90% of the population lives. Awareness of the need to improve statistical data in Bangladesh has been increasing, particularly in regard to the development of rural areas. An accurate statistical profile of rural Bangladesh is crucial to the formation, implementation and evaluation of rural development programs. A Seminar on Statistics for Rural Development will be held from June 18-20, 1980. The primary objectives of the Seminar are to make an exhaustive analysis of the current availability of statistics required for rural development programs and to consider methodological and operational improvements toward building up an adequate data base.  相似文献   
99.
As parts of a global network, foreign-owned subsidiaries enjoy privileged access to knowledge sources both internal (within their multinational group) and external (involving other organizations in the host location), and this has proven especially relevant in their assumption of greater creative responsibilities that increase the technological capabilities of their multinational group. This study investigates whether external and internal relational embeddedness are mutually reinforcing (complementary) or whether they act separately in explaining superior innovation performance of foreign-owned subsidiaries in terms of a greater propensity to obtain radical innovations. The empirical analysis uses both direct and indirect tests to evaluate the complementarity, as well as a rich firm-level panel data on foreign subsidiaries, extracted from a census of Colombian manufacturing firms for the period 2008–2014. Our findings reveal that external relational embeddedness in isolation (without internal embeddedness) has a positive impact on performance only in terms of incremental innovation, while internal embeddedness alone (without external embeddedness) has no effect on the innovation performance of subsidiaries. However, we find that a complementary and dynamic relationship exists between external and internal linkages to spur radical innovation outcomes, which in turn are related to the competence-creating roles in foreign subsidiaries as prior literature has shown.  相似文献   
100.
Many energy technologies that can provide reliable, low-carbon electricity generation are confined to nations that have access to robust technical and economic capabilities, either on their own or through geopolitical alliances. Equally important, these nations maintain a degree of institutional capacity that could lower the risks associated with deploying emergent energy technologies such as advanced nuclear or carbon capture and storage. The complexity, expense, and scrutiny that come with building these facilities make them infeasible choices for most nations. This paradigm is slowly changing, as the pressing need for low-carbon electricity generation and ongoing efforts to develop modular nuclear and carbon capture technologies have opened the door for potentially wider markets, including in nations without substantial institutional capacity. Here, using advanced nuclear technologies as our testbed, we develop new methods to evaluate national readiness for deploying complex energy infrastructure. Specifically, we use Data Envelopment Analysis—a method that eliminates the need for expert judgment—to benchmark performance across nations. We find that approximately 80% of new nuclear deployment occurs in nations that are in the top two quartiles of institutional and economic performance. However, 85% of potential low-carbon electricity demand growth is in nations that are in the bottom two quartiles of performance. We offer iconic paradigms for deploying nuclear power in each of these clusters of nations if the goal is to mitigate risk. Our research helps redouble efforts by industry, regulators, and international development agencies to focus on areas where readiness is low and risk correspondingly higher.  相似文献   
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