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91.
人口承载力指标系的建立及量化   总被引:5,自引:0,他引:5  
有关人口承载力概念、内涵、指标体系与评价模型的研究在我国已取得了长足的发展。纵观渊源,可归结为从容量、阈值、能力等角度分别进行的研究。然而,全球经济一体化进程的不断推进,开放式条件分析框架下的人口承载力已从简单意义上的"量"演变为复杂状况下"量"与"性"才能研究的目标对象。开放式条件作为现今必需的研究背景,结合环境和资源的相对稳定性、人口规模与经济规模大小的适应性,有必要建立衡量和评价人口承载力"质量"的指标系。通过围绕社会经济状况、环境资源、区域人口状况三系统讨论了人口承载力指标系的构建与量化。  相似文献   
92.
The privatization process and foreign direct investments (FDI) are among the most important economic issues in transitional countries. FDI has enormous influence on transitional countries that need serious structural changes. In this paper we will study FIAT’s decision to invest in the Serbian automotive industry. We will try to rationalize FIAT’s decision because Serbian car manufacturer ZASTAVA was not the only alternative for FIAT to invest in the Balkans. In order to justify FIAT’s decision we will apply the Mullins model of horizontal and vertical FDI, examine the importance of the cooperating history between two car manufacturers and compare macroeconomic conditions and Global Competitiveness of Serbia and Romania, which was the main alternative for FIAT. Finally, we will also try to explain why FIAT decided to announce the investment at the end of political campaign in Serbia when pools gave anti-European parties higher chances for victory, instead of waiting to see the outcome of the elections.
Stefania TattoniEmail:
  相似文献   
93.
Nongovernmental organizations (NGOs) are established not with the aim of making profits but rather to provide social values by implementing different projects and activities. Transmitting complete information about these projects to society is a key element of transparency, as they operate within an atmosphere of public trust. Although there is a large body of literature on transparency in NGOs from a global perspective, very little research has been conducted on transparency within the area of projects and activities. This study takes a deeper look at this line and contributes to the literature on transparency in NGOs by proposing an index to measure the information transparency of the projects implemented by these organizations. The index captures three dimensions of the information about the projects (technical, financial, and scope) and makes it possible to: analyze the level of transparency of the portfolio of projects, detect the specific aspects that could be improved in each organization, and carry out comparisons among organizations.  相似文献   
94.
This paper extends the univariate time series smoothing approach provided by penalized least squares to a multivariate setting, thus allowing for joint estimation of several time series trends. The theoretical results are valid for the general multivariate case, but particular emphasis is placed on the bivariate situation from an applied point of view. The proposal is based on a vector signal-plus-noise representation of the observed data that requires the first two sample moments and specifying only one smoothing constant. A measure of the amount of smoothness of an estimated trend is introduced so that an analyst can set in advance a desired percentage of smoothness to be achieved by the trend estimate. The required smoothing constant is determined by the chosen percentage of smoothness. Closed form expressions for the smoothed estimated vector and its variance-covariance matrix are derived from a straightforward application of generalized least squares, thus providing best linear unbiased estimates for the trends. A detailed algorithm applicable for estimating bivariate time series trends is also presented and justified. The theoretical results are supported by a simulation study and two real applications. One corresponds to Mexican and US macroeconomic data within the context of business cycle analysis, and the other one to environmental data pertaining to a monitored site in Scotland.  相似文献   
95.
The randomized response technique (RRT) is an important tool, commonly used to avoid biased answers in survey on sensitive issues by preserving the respondents’ privacy. In this paper, we introduce a data collection method for survey on sensitive issues combining both the unrelated-question RRT and the direct question design. The direct questioning method is utilized to obtain responses to a non sensitive question that is related to the innocuous question from the unrelated-question RRT. These responses serve as additional information that can be used to improve the estimation of the prevalence of the sensitive behavior. Furthermore, we propose two new methods for the estimation of the proportion of respondents possessing the sensitive attribute under a missing data setup. More specifically, we develop the weighted estimator and the weighted conditional likelihood estimator. The performances of our estimators are studied numerically and compared with that of an existing one. Both proposed estimators are more efficient than the Greenberg's estimator. We illustrate our methods using real data from a survey study on illegal use of cable TV service in Taiwan.  相似文献   
96.
In this paper, a generalized difference-based estimator is introduced for the vector parameter β in partially linear model when the errors are correlated. A generalized-difference-based almost unbiased two-parameter estimator is defined for the vector parameter β. Under the linear stochastic constraint r = Rβ + e, we introduce a new generalized-difference-based weighted mixed almost unbiased two-parameter estimator. The performance of this new estimator over the generalized-difference-based estimator and generalized- difference-based almost unbiased two-parameter estimator in terms of the MSEM criterion is investigated. The efficiency properties of the new estimator is illustrated by a simulation study. Finally, the performance of the new estimator is evaluated for a real dataset.  相似文献   
97.
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   
98.
Voting procedure is an important mechanism for public choice in collective bodies such as international organizations. This paper measures and compares IMF member countries’ voting power before the 2008 reform and after the 2010 reform on the basis of datasets on IMF quotas and voting rights distribution provided by IMF. Our study verifies that IMF’s quotas and voting rights reforms do help to reduce the voting power gap among member countries. The 2008 and 2010 reforms produce a greater improvement in emerging members’ voting power under the 70 percent majority rule than the 85 percent rule; the 70 percent majority rule means the United States would lose its absolute veto. Moreover, the paper disproves the underlying assumption that regards a member’s voting power as proportional to its voting rights. Countries with different amounts of voting rights can still have the same voting power.  相似文献   
99.
This paper explores the relationship between governance and social innovation in the area of organizations. In order to understand that relationship, we offer a model that links the absorptive capacity of knowledge [Cohen and Levinthal 1990. “Absorptive Capacity: A new Perspective on Learning and Innovation.” Administrative Science Quarterly 35 (1): 128–152] with open innovation [Chesbrough and Di Minin 2014. “Open Social Innovation.” In New Frontiers in Open Innovation, edited by H. Chesbrough, W. Vanhaverbeke, and J. West, 169–187. Oxford: Oxford University Press]. On the basis of the pilot study Regional Social Innovation Index carried out in the Basque Country (Spain), we empirically explore three types of governance (social, inter-organizational, and sustainable) in social innovation projects propelled by four types of key agents at a regional level: profit and non-profit organizations, universities, and technology centers. The proposed governance Index in Social Innovation contributes to discussions about governance and social innovation at a micro level and, and to the debate about the production of indicators in social innovation.  相似文献   
100.
Objective: To analyze the impact of age, BMI and sex hormone on aging males’ symptoms (AMS) and the 5-item version of the international index of erectile function (IIEF-5) scores in middle-aged and elderly Chinese men.

Methods: A population-based cross-sectional study was conducted in Jiashan County. A total of 969 men, aged between 40 and 80 years old, were admitted. Physical examination and the sex hormones were measured, and AMS and IIEF-5 scores were assessed.

Results: The oneway ANOVA analysis indicated older age groups had higher AMS total-scores, somatic and sexual sub-scores, and lower IIEF5 scores (all p?rpairwise) analyses showed the significant associations between AMS and age or sex hormone (cFT, Bio-T, SHBG, and LH) levels, and similar for IIEF5. However, when age was adjusted, the correlation coefficients (rpartial) weakened, and correlation significance disappeared, except LH (for AMS: rpartial?=?0.096, p?=?.009; for IIEF-5: rpartial?= ?0.140, p?=?.001). Multiple linear regressions confirmed the influence of increased age and LH on the AMS and IIEF5 scores.

Conclusion: CFT, Bio-T and SHBG failed to yield any additional predicting information when age was adjusted. To improve the male reproductive health, future research should pay more attention on aging-related comorbidities and how to improve general wellness.  相似文献   
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