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221.
    
We merge marital history data for respondents in the National Survey of Families and Households with census data describing the sex composition of their local marriage markets and occupations to examine the impact of the availability of spousal alternatives on marital dissolution. Proportional hazards regression models that adjust for left truncation reveal that the risk of divorce is highest in geographically defined marriage markets where either husbands or wives encounter numerous alternatives to their current partner. Couples are also more likely to divorce when the wife works in an occupation having relatively many men and few women, but husbands' occupational sex ratio has no effect on the risk of marital dissolution. The destabilizing effects of the availability of spousal alternatives in the local marriage market and in wives' occupations are equally strong among couples with many and few other risk factors for divorce. Our findings suggest that spouses' structural opportunities to form alternative opposite‐sex relationships are an important factor in explaining why some couples divorce.  相似文献   
222.
    
The classical chi‐square test of goodness of fit compares the hypothesis that data arise from some parametric family of distributions, against the nonparametric alternative that they arise from some other distribution. However, the chi‐square test requires continuous data to be grouped into arbitrary categories. Furthermore, as the test is based upon an approximation, it can only be used if there are sufficient data. In practice, these requirements are often wasteful of information and overly restrictive. The authors explore the use of the fractional Bayes factor to obtain a Bayesian alternative to the chi‐square test when no specific prior information is available. They consider the extent to which their methodology can handle small data sets and continuous data without arbitrary grouping.  相似文献   
223.
There is an urgent demand for the examination of the critical perceptions of new kinds of ‘development’ which are emerging in the Global South in response to—and often opposed to—the global capitalist political economy. This article discusses the case of contemporary Bolivia in which indigenous political alternatives have emerged as the resistance to economic globalization and the powers of capital accumulation, as well as to the cultural and epistemological commitments of the Western order. Through an ethnographic approach, it examines the emergence and shortcomings of the notion of vivir bien—a local, decolonial, indigenous concept of good life—as state policy. It argues that despite its transformative potential, the translation of vivir bien discourses into state practices has not been, to a large degree, achieved.  相似文献   
224.
This paper introduces a new notion of consistency for social choice functions, called self‐selectivity, which requires that a social choice function employed by a society to make a choice from a given alternative set it faces should choose itself from among other rival such functions when it is employed by the society to make this latter choice as well. A unanimous neutral social choice function turns out to be universally self‐selective if and only if it is Paretian and satisfies independence of irrelevant alternatives. The neutralunanimous social choice functions whose domains consist of linear order profiles on nonempty sets of any finite cardinality induce a class of social welfare functions that inherit Paretianism and independence of irrelevant alternatives in case the social choice function with which one starts is universally self‐selective. Thus, a unanimous and neutral social choice function is universally self‐selective if and only if it is dictatorial. Moreover, universal self‐selectivity for such functions is equivalent to the conjunction of strategy‐proofness and independence of irrelevant alternatives or the conjunction of monotonicity and independence of irrelevant alternatives again.  相似文献   
225.
    
Optimal designs for logistic models generally require prior information about the values of the regression parameters. However, experimenters usually do not have full knowledge of these parameters. We propose a design that is D-optimal on a restricted design region. This design assigns an equal weight to design points that contain more information and ignores those design points that contain less information about the regression parameters. The design can be constructed in practice by means of the rank order of the outcome variances. A numerical study compares the proposed design with the D-optimal and completely balanced designs in terms of efficiency.  相似文献   
226.
    
Calculations of local influence curvatures and leverage have been well developed when the parameters are unrestricted. In this article, we discuss the assessment of local influence and leverage under linear equality parameter constraints with extensions to inequality constraints. Using a penalized quadratic function we express the normal curvature of local influence for arbitrary perturbation schemes and the generalized leverage matrix in interpretable forms, which depend on restricted and unrestricted components. The results are quite general and can be applied in various statistical models. In particular, we derive the normal curvature under three useful perturbation schemes for generalized linear models. Four illustrative examples are analyzed by the methodology developed in the article.  相似文献   
227.
    
This article provides the analytical characterization of the inverse of the information matrix for second-order SPD. A particular feature of these explicit expressions is that they are functions of the design parameters enabling the development of analytical functions to efficiently compute exact design optimality criteria. The application of these analytical expressions is demonstrated using the generalized variance of the parameter estimates for second-order SPD. An example illustrating the use of these expressions is also presented.  相似文献   
228.
    
In this note, we show that the estimator and the following results given by Zhong and Yang (2007 Zhong , Z. , Yang , H. ( 2007 ). Ridge estimation to the restricted linear model . Commun. Statist. Theor. Meth. 36 : 20992115 .[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) are the same with that of Groß (2003 Groß , J. ( 2003 ). Restricted ridge estimation . Statist. Probab. Lett. 65 : 5764 .[Crossref], [Web of Science ®] [Google Scholar]).  相似文献   
229.
    
In this article, the parameter estimators in singular linear model with linear equality restrictions are considered. The restricted root estimator and the generalized restricted root estimator are proposed and some properties of the estimators are also studied. Furthermore, we compare them with the restricted unified least squares estimator and show their sufficient conditions under which their superior over the restricted unified least squares estimator in terms of mean squares error, and discuss the choice of the unknown parameters of the generalized restricted root estimator.  相似文献   
230.
    
In this article, we introduce a ridge estimator for the vector of parameters β in a semiparametric model when additional linear restrictions on the parameter vector are assumed to hold. We also obtain the semiparametric restricted ridge estimator for the parametric component in the semiparametric regression model. The ideas in this article are illustrated with a data set consisting of housing prices and through a comparison of the performances of the proposed and related estimators via a Monte Carlo simulation.  相似文献   
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