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1.
The new approach to assisting developing countries inspired by the Paris Declaration emphasises greater recipient control over the funds provided, thus confining donors’influence to upstream points in the policy process, where political aspects of development co‐operation become more important. Understanding better the role that power plays in the aid relationship will be critical to the implementation of the Declaration. This article shows how the political science literature can inform this set of issues. It argues that an understanding of aspects of power illuminates the challenges involved in transforming relations between donors and recipient governments as well as between governments and civil society organisations.  相似文献   
2.
The problem of the allocation of experimental units to experimental groups is studied within the context of generalized linear models. Optimal designs for the estimation of linear combinations of linear predictors are characterized, using concepts from the theory of optimal design. If there is only one linear combination of interest, then the D-optimal allocation is equivalent to the well-known Neyman allocation of subsamples in stratified sampling. However, if the number of linear combinations equals the number of design points, or experimental groups, then the equal replication of all design points is D-optimal. For cases in between, there are no easily accessible general solutions to the problem, although some particular cases are solved, including: i estimation of the n- 1 possible comparisons with a control group in an n-point, one-factor design; and ii estimation of 2 one or two of the four natural parameters of a 2 factorial design. The A-optimal allocations are determined in general.  相似文献   
3.
Purpose: We aimed at evaluating androgen status (serum testosterone [TT] and estimated free testosterone [eFT]) and its determinants in non-diabetic elderly men with heart failure (HF). Additionally, we investigated its associations with body composition and long-term survival.

Methods: Seventy three non-diabetic men with HF and 20 healthy men aged over 55?years were studied. Echocardiography, 6-min walk test, grip strength, body composition measurement by DEXA method were performed. TT, sex hormone binding globulin, NT-proBNP, and adipokines (adiponectin and leptin) were measured. All-cause mortality was evaluated at six years of follow-up.

Results: Androgen status (TT, eFT) was similar in elderly men with HF compared to healthy controls (4.79?±?1.65 vs. 4.45?±?1.68?ng/ml and 0.409?±?0.277 vs. 0.350?±?0.204?nmol/l, respectively). In HF patients, TT was positively associated with NT-proBNP (r=?0.371, p?=?0.001) and adiponectin levels (r?=?0.349, p?=?0.002), while inverse association was noted with fat mass (r?=??0.413, p?<?0.001). TT and eFT were independently determined by age, total fat mass and adiponectin levels in elderly men with HF (p?<?0.05 for all). Androgen status was not predictor for all-cause mortality at six years of follow-up.

Conclusions: In non-diabetic men with HF, androgen status is not altered and is not predictive of long-term outcome.  相似文献   
4.
The objective of this study was to compare adolescents' attitudes toward schizophrenia, depression, and posttraumatic stress disorder (PTSD). Stigmatizing attitudes toward these three mental disorders were evaluated in 325 senior students from medical, commercial, and grammar high schools in Croatia using a 45-item questionnaire. Results indicated that stigmatizing attitudes toward PTSD were at the same level as attitudes toward depression and were less stigmatizing than were attitudes toward schizophrenia. Negative attitudes were the lowest among medical students. Gender differences existed only for attitudes toward depression. Stigmatizing attitudes toward PTSD were not as high as expected. All of the students believed mental disorders are different from other disorders. Specific knowledge of psychiatry has been shown to reduce stigma. The nonaddictive nature of psychotropic medications should receive greater emphasis when teaching psychiatry.  相似文献   
5.
Chandra S  Kuljanin G  Wray J 《Demography》2012,49(3):857-865
Estimates of worldwide mortality from the influenza pandemic of 1918-1919 vary widely, from 15 million to 100 million. In terms of loss of life, India was the focal point of this profound demographic event. In this article, we calculate mortality from the influenza pandemic in India using panel data models and data from the Census of India. The new estimates suggest that for the districts included in the sample, mortality was at most 13.88 million, compared with 17.21 million when calculated using the assumptions of Davis (1951). We conclude that Davis' influential estimate of mortality from influenza in British India is overstated by at least 24%. Future analyses of the effects of the pandemic on demographic change in India and worldwide will need to account for this significant downward revision.  相似文献   
6.
Optimal designs for a logistic regression model with over-dispersion introduced by a beta-binomial distribution are characterized. Designs are defined by a set of design points and design weights as usual but, in addition, the experimenter must also make a choice of a sub-sampling design specifying the distribution of observations on sample sizes. In an earlier work it has been shown that Ds-optimal sampling designs for estimation of the parameters of the beta-binomial distribution are supported on at most two design points. This admits a simplified approach using single sample sizes. Linear predictor values for Ds-optimal designs using a common sample size are tabulated for different levels of over-dispersion and choice of subsets of parameters.  相似文献   
7.
Many studies have refuted the opinion that urban floras are poor in total species number and characterized primarily by neophytes. Also, it has been proved that urban flora differs from its surroundings, and at the same time reflects its richness. Our study focused on urban flora, structure and similarities, and the possible correlation with the urban attributes. Therefore, we selected 11 cities in Southeast Europe, which differ in the development of transportation networks (roads, rails and inland waterways) and population size. Next, we compared two sets of data (structure of urban flora and urban attributes) to define the correlation patterns. Analyzed urban floras were primarily distinguished by a total number of species, number of unique species and neophytes. Belgrade is a city with the highest urbanization level, the most species and the highest number of unique species and neophytes as well. Kosovska Mitrovica, Grocka and Po?arevac stand out by floristic richness. These cities have a high number of species, yet a small proportion of neophytes. Other cities are characterized by similar floristic structure, with a relatively similar proportion of neophytes and approximately similar number of unique species in relation to the total number. It can be concluded that other factors beside the chosen urban attributes have additional effects on floristic structure, except for the factor - the presence of neophytes. This is in accordance with predefining subjects, since urban attributes were chosen based on knowledge about important corridors for invasive species.  相似文献   
8.
In this work, we study D s -optimal design for Kozak's tree taper model. The approximate D s -optimal designs are found invariant to tree size and hence create a ground to construct a general replication-free D s -optimal design. Even though the designs are found not to be dependent on the parameter value p of the Kozak's model, they are sensitive to the s×1 subset parameter vector values of the model. The 12 points replication-free design (with 91% efficiency) suggested in this study is believed to reduce cost and time for data collection and more importantly to precisely estimate the subset parameters of interest.  相似文献   
9.
10.
We study the approximability of the weighted edge-dominating set problem. Although even the unweighted case is NP-Complete, in this case a solution of size at most twice the minimum can be efficiently computed due to its close relationship with minimum maximal matching; however, in the weighted case such a nice relationship is not known to exist. In this paper, after showing that weighted edge domination is as hard to approximate as the well studied weighted vertex cover problem, we consider a natural strategy, reducing edge-dominating set to edge cover. Our main result is a simple -approximation algorithm for the weighted edge-dominating set problem, improving the existing ratio, due to a simple reduction to weighted vertex cover, of 2r WVC, where r WVC is the approximation guarantee of any polynomial-time weighted vertex cover algorithm. The best value of r WVC currently stands at . Furthermore we establish that the factor of is tight in the sense that it coincides with the integrality gap incurred by a natural linear programming relaxation of the problem.  相似文献   
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