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831.
韩国经济结构变化与CO2排放关系及启示   总被引:1,自引:0,他引:1       下载免费PDF全文
金继红 《统计研究》2007,24(2):60-65
摘  要:经济发展和环境问题,日益受到全世界的高度重视。本文利用投入产出分析方法,对韩国的经济结构变化与二氧化碳排放关系进行实证分析,得出韩国在1980年代后期的内需主导型发展模式带来了环境负荷的减少;1990年代前期的出口主导型发展模式带来了环境负荷的增加。结果表明韩国是出口环境负荷相对大的产品,也就是背负先进国家的环境负荷实现经济增长,对我国的经济发展与环境问题具有重要的借鉴意义。  相似文献   
832.
Researchers striving to ensure rigor in their scientific findings face a common pitfall: Endogeneity. To tackle this problem, scholars have increasingly adopted instrumental variables estimation (IVE). Although there are many published works showing how IVE should be used, many applied researchers still have trouble understanding how to use the method correctly. In this article, we provide a methodological overview of IVE by discussing the underlying conditions valid instruments must satisfy as well as common mistakes made in using IVE. Using simulated data, we further demonstrate the sensitivity of IVE to violations of its conditions. We then take stock of the literature in a social science discipline (i.e., leadership research) and provide insights regarding trends and shortcomings in the application of IVE. Based on our review, we categorize the different types of instruments used and discuss the potential appropriateness of each type. We conclude by providing non–technical guidelines targeted at the study design, analysis, and reporting phases, which will help applied social science researchers to ensure they use IVE correctly.  相似文献   
833.
围绕价值管理, 分析了基于职能管理的管理知识体系存在的问题, 即: 忽视创新; 对企业 效用的存在假设越来越偏离实际, 从而导致对企业组织中激励的认识偏差, 甚至出现目的与手 段的倒置; 对信息的假设和运用有误; 缺乏系统与综合, 忽视整合的作用. 在此基础上, 提出了 以价值管理为核心概念建立管理知识体系的观点, 并建立了相应的6 I’s 管理模式的框架, 分 析了有关要素的内涵.  相似文献   
834.
ABSTRACT

Intimate partner violence (IPV) is a prevalent issue in all relationship configurations, including lesbian, gay, bisexual, transgender, queer, and two-spirit (LGBTQ2S) relationships. While the experiences of LGBTQ2S IPV survivors are understood, there are issues, needs, and challenges associated with service provision for them. Semi-structured interviews were conducted with a sample (N = 10) of professionals (e.g., counselors, shelter managers, program directors) affiliated with organizations that provide services for IPV survivors in Ontario, Canada. Participants answered questions pertaining to the inclusion of LGBTQ2S IPV survivors into their existing services, and what service provision should look like. Data was analyzed using a thematic analysis to uncover themes that reflected participants' responses. The data was organized into recommendations for service provision at three different levels: direct service provision, organizational transformation, and underlying principles and values. Findings reveal suggestions for service providers to consider modifying their current organizations, to adequately include LGBTQ2S IPV survivors.  相似文献   
835.
Introduction: Inflammation and angiogenesis are known to play a role in the development prostate tumors. The present study was designed to assess the levels of markers of inflammation and angiogenesis like interleukin-17 (IL-17) and angiopoietin-2 (ANGPT2) levels and their association with prostate size in patients with benign prostatic hyperplasia (BPH).

Materials and methods: 42 BPH cases and 42 controls were enrolled in the study. IL-17 and ANGPT2 were estimated in both the groups.

Results: IL-17 and ANGPT2 were significantly increased in BPH cases when compared with controls. Multivariate analysis showed that ANGPT2 predicts the prostate size in patients with BPH (R2?=?0.203, beta?=?0.355, p?=?0.028). Linear regression analysis showed that IL-17 was significantly associated with ANGPT2 in BPH cases (R2?=?0.129, beta – 0.359, p?=?0.020).

Conclusions: We conclude that IL-17 and ANGPT2 are elevated in BPH cases and ANGPT2 was associated with IL-17 and prostate size.  相似文献   
836.
Three-mode analysis is a generalization of principal component analysis to three-mode data. While two-mode data consist of cases that are measured on several variables, three-mode data consist of cases that are measured on several variables at several occasions. As any other statistical technique, the results of three-mode analysis may be influenced by missing data. Three-mode software packages generally use the expectation–maximization (EM) algorithm for dealing with missing data. However, there are situations in which the EM algorithm is expected to break down. Alternatively, multiple imputation may be used for dealing with missing data. In this study we investigated the influence of eight different multiple-imputation methods on the results of three-mode analysis, more specifically, a Tucker2 analysis, and compared the results with those of the EM algorithm. Results of the simulations show that multilevel imputation with the mode with the most levels nested within cases and the mode with the least levels represented as variables gives the best results for a Tucker2 analysis. Thus, this may be a good alternative for the EM algorithm in handling missing data in a Tucker2 analysis.  相似文献   
837.
In the recent years, the notion of data depth has been used in nonparametric multivariate data analysis since it gives natural ‘centre-outward’ ordering of multivariate data points with respect to the given data cloud. In the literature, various nonparametric tests are developed for testing equality of location of two multivariate distributions based on data depth. Here, we define two nonparametric tests based on two different test statistic for testing equality of locations of two multivariate distributions. In the present work, we compare the performance of these tests with the tests developed by Li and Liu [New nonparametric tests of multivariate locations and scales using data depth. Statist Sci. 2004;(1):686–696] for testing equality of locations of two multivariate distributions. Comparison in terms of power is done for multivariate symmetric and skewed distributions using simulation for three popular depth functions. Application of tests to real life data is provided. Conclusion and recommendations are also provided.  相似文献   
838.
839.
We discuss a one-sample location test that can be used when the dimension and the sample size are large. It is well-known that the power of Hotelling’s test decreases when the dimension is close to the sample size. To address this loss of power, some non exact approaches were proposed, e.g., Dempster (1958 Dempster, A.P. (1958). A high dimensional two sample significance test. Ann. Math. Stat. 29:9951010.[Crossref] [Google Scholar], 1960 Dempster, A.P. (1960). A significance test for the separation of two highly multivariate small samples. Biometrics 16:4150.[Crossref], [Web of Science ®] [Google Scholar]), Bai and Saranadasa (1996 Bai, Z.D., Saranadasa, H. (1996). Effect of high dimension: by an example of a two sample problem. Stat. Sin. 6:311329.[Web of Science ®] [Google Scholar]), and Srivastava and Du (2008 Srivastava, M.S., Du, M. (2008). A test for the mean vector with fewer observations than the dimension. J. Multivariate Anal. 99:386402.[Crossref], [Web of Science ®] [Google Scholar]). In this article, we focus on Hotelling’s test and Dempster’s test. The comparative merits and demerits of these two tests vary according to the local parameters. In particular, we consider the situation where it is difficult to determine which test should be used, that is, where the two tests are asymptotically equivalent in terms of local power. We propose a new statistic based on the weighted averaging of Hotelling’s T2-statistic and Dempster’s statistic that can be applied in such a situation. Our weight is determined on the basis of the maximum local asymptotic power on a restricted parameter space that induces local asymptotic equivalence between Hotelling’s test and Dempster’s test. Numerical results show that our test is more stable than Hotelling’s T2-statistic and Dempster’s statistic in most parameter settings.  相似文献   
840.
The phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathways and Bcl-2 family play a central role in prostate cancer (PC). The aim was to determine influence in the biochemical progression in PC. To evaluate the association between clinic pathological and immunohistochemical variables, Spearman’s test was performed. Log-rank test and Kaplan–Meier curves were used for survival comparisons. To explore the correlation of the studied immunohistochemical parameters and the established prognostic variables with biochemical progression, univariate and multivariate Cox proportional Hazard regression analyses were performed. Spearman analysis showed correlation between stroma expression and tumor expression of PI3K with biochemical progression (p?=?.009, p?=?.004), respectively, and tumor immunohistochemical score with biochemical progression (p?=?.051). In the multivariate Cox regression model, only PI3K was retained as independent predictors of biochemical progression. In stroma expression, PI3K is (HR 0.172, 95% CI 0.065–0.452, p?=?.000); tumor expression, PI3K is (HR 0.087, 95% CI 0.026–0.293, p?=?.000), and tumor immunohistochemical score (HR 0.382, 95% CI 0.209–0.697 p?=?.002). Our results suggest a role for prostatic expression of PI3K was prognostic markers for PC. PI3K/AKT/mTOR and Bcl-2 family are becoming an important therapeutic target and predictive biomarkers of onset and progression of PC.  相似文献   
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