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This paper discusses a problem concerning intertemporal decision-making under uncertainty when its subject has psychological biases. Here, we consider an investment company as a decision maker that invests money from investors in a financial asset and pays some dividend every period depending on the performance of the investment. On the other hand, we assume investors have such psychological biases as inconsistent time preference and loss aversion. Through numerical experiments we show that the optimal dividend distribution under inconsistent time preference and loss aversion is quite different from the distribution without these psychological factors, and that combinations of the two factors produce various patterns of dividend distribution.  相似文献   
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Using data from the 2000 U.S. Census, we investigate the schooling and earnings of single-race and multi-race Native Americans. Our analysis distinguishes between Single-Race Native Americans, biracial White Native Americans, biracial Hispanic-White Native Americans, and biracial Black Native Americans. Further differentiating by gender, the results indicate significant variation in socioeconomic attainments across these different Native American groups although almost all of them are in some way disadvantaged relative to non-Hispanic, non-Native American whites. The most disadvantaged group tends to be Single-Race Native Americans who have the lowest levels of schooling as well as lower earnings relative to non-Hispanic, non-Native American whites who are comparable in terms of schooling, age, and other basic demographic characteristics. The results demonstrate notable differentials by the racial/ethnic type of Native American group as well as by gender. In the case of men, all of the Native American groups have clear socioeconomic disadvantages. One contrast is that migration slightly increases the earnings of men but it slightly decreases the earnings of women. We interpret these findings as underscoring how measured socioeconomic differentials between demographic groups are significantly affected by the categorization of race/ethnicity in surveys and by how persons choose to be enumerated in terms of those categories.  相似文献   
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红外吸收峰的位置波动可能由单一谱带的实际频移或是邻近重叠谱带相对强度的变化而产生。本文通过主成分分析法(PCA)有力地证明了光谱位置波动的根源往往归因于后一种机理。PCA能灵敏有效地区分单一谱带的实际频移与由重叠谱带相对强度变化所产生的最大峰移。对于由分子相互作用强度变化所诱导,并在振动光谱领域较为常见的所谓带移的概念,往往由于其隐含了谱带的固有频移而有些概念误导。在许多红外光谱中,峰极大值表面的位移,一般产生于两条重叠谱带相对贡献的变化,而不是分子相互作用强度变化所诱导的单一谱带的缓慢频移。这个观点可以帮助我们解释振动光谱所探测到的分子相互作用。  相似文献   
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The generalized estimating equation is a popular method for analyzing correlated response data. It is important to determine a proper working correlation matrix at the time of applying the generalized estimating equation since an improper selection sometimes results in inefficient parameter estimates. We propose a criterion for the selection of an appropriate working correlation structure. The proposed criterion is based on a statistic to test the hypothesis that the covariance matrix equals a given matrix, and also measures the discrepancy between the covariance matrix estimator and the specified working covariance matrix. We evaluated the performance of the proposed criterion through simulation studies assuming that for each subject, the number of observations remains the same. The results revealed that when the proposed criterion was adopted, the proportion of selecting a true correlation structure was generally higher than that when other competing approaches were adopted. The proposed criterion was applied to longitudinal wheeze data, and it was suggested that the resultant correlation structure was the most accurate.  相似文献   
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An extension of a result about the estimation in Karlin and Rubin is given for the following case:The sample space, the parameter space and the decision space are subsets of a multi-dimensional Euclidean space, there is defined a suitable partial ordering in each of spaces, and a probability distribution has monotone likelihood ratio with respect to the partial orderings (see Ishii, 1976). In the special case when the loss function is quadratic a simple proof of a result in Karlin and Rubin is given. Stein's estimators are discussed as examples.  相似文献   
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This paper discusses nonparametric estimation of nonlinear dynamical system models by a method of metric-based local linear approximation. We assume no functional form of a given model but estimate it from experimental data by approximating the curve implied by the function by the tangent plane around the neighborhood of a tangent point. To specify an appropriate neighborhood, we prepare a metric defined over the Euclidean space in which the curve exists and then evaluate the closeness to the tangent point according to the distances. The proposed method differs from the first order polynomial modeling in discerning the metric and the weighting function, but the first order polynomial modeling with Gaussian kernels is shown to be a special version of the proposed method. Simulation studies and application to ECG signals show the proposed method is easy to manipulate and has performance comparable to or better than the first order local polynomial modeling.  相似文献   
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Abstract

In order to evaluate the progress of a health service, certain criteria (indices) should be established and monitored. If any health center wishes to compare its situation with others, a valid instrument for measuring morbidity is required, and the criteria must be in conformity with national and/or international standards. This paper details methods of producing health indices from medical diagnoses. It is based on experience in a health service for students. Three systems are offered to cover centers with and without computer facilities: 1) a minimum for student health services; 2) the “minima” requested by the World Health Organization; 3) a classification of conditions of special interest in student health. It is strongly recommended that the International Classification of Diseases (ICD-9) of the World Health Organization be accepted as the local and international basis for these diagnostic categories.

“Epidemic Non-A, Non-B Hepatitis in Nepal: Recovery of a Possible Etiologic Agent and Transmission Studies in Marmosets,” MARK A. KANE, et al. An epidemic of non-A, non-B hepatitis occurred in Kathmandu Valley, Nepal, during 1981–1982, with approximately 7.6% of households and 1.4% of individuals affected. Cases occurred preponderantly in the 15- to 34-year-old age group (70%), with most cases (75%) occurring in males. A high mortality rate (21%) occurred in pregnant women admitted to the hospital. No single water source was implicated, but epidemic peaks occurred during monsoon rains, and multiple opportunities for enteric transmission existed. One of eight patient stools examined by immune electron microscopy revealed aggregated, antibody-coated, 27-nm viruslike particles when convalescent serum samples were used as sources of antibody. Inoculation of two chimpanzees and four marmosets with a suspension of this stool resulted in elevated liver enzyme activity in three marmosets. Fecal excretion of 27-nm particles during the acute phase of disease (with temporally coincident antigen activity by radioimmunoassay) was observed in one marmoset, which also developed convalescent antibody against the particles in the original inoculum. (Journal of the American Medical Association 1984;252:3140–3145.)

“High-dose Vitamin C Versus Placebo in the Treatment of Patients with Advanced Cancer who Have Had No Prior Chemotherapy; A Randomized Double-Blind Comparison,” CHARLES G. MOERTEL, et al. It has been claimed that high-dose vitamin C is beneficial in the treatment of patients with advanced cancer, especially patients who have had no prior chemotherapy. In a double-blind study 100 patients with advanced colorectal cancer were randomly assigned to treatment with either high-dose vitamin C (10 g daily) or placebo. Overall, these patients were in very good general condition, with minimal symptoms. None had received any previous treatment with cytotoxic drugs. Vitamin C therapy showed no advantage over placebo therapy with regard to either the interval between the beginning of treatment and disease progression or patient survival. Among patients with measurable disease, none had objective improvement. On the basis of this and our previous randomized study, it can be concluded that high-dose vitamin C therapy is not effective against advanced malignant disease regardless of whether the patient has had any prior chemotherapy. (New England Journal of Medicine 1985;312:137–41.)  相似文献   
10.
Using recent American Community Survey data, this study investigates socioeconomic attainments of six ethnic groups of Southeast Asian Americans. Findings show that the educational attainment of Filipinos, Vietnamese, and Thai is higher than that of whites, while the educational attainment of Cambodians, Hmong, and Laotians is lower than that of whites. Regarding earnings, Southeast Asian American women are generally not disadvantaged relative to white women, but Southeast Asian American men tend to have lower earnings than white men after controlling for education and other demographic factors such as age, metropolitan residence, and region. We conclude that Cambodians, Hmong, and Laotians are the most disadvantaged groups among Southeast Asian Americans and that most Southeast Asian American male groups tend to be at least slightly disadvantaged in the labor market at least after controlling for metropolitan residence and region.  相似文献   
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