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31.
Abstract

European and Italian libraries are strongly involved in efforts to facilitate access to European information resources. The Italian union catalogue of serials has evolved from a traditional catalog to a sophisticated resource that provides access to serials services. Serials control is the most recent service of the union catalog with features for end users and professional staff. The software is BASIS Techlib by ID Technology (Italy), affinity partner of Open Text (USA). The ability to customize features presents a very satisfactory, easy-to-use product that might be considered interesting for union catalogs in other countries. Serials Review 2003; 29:169–178.  相似文献   
32.
Effective implementation of likelihood inference in models for high‐dimensional data often requires a simplified treatment of nuisance parameters, with these having to be replaced by handy estimates. In addition, the likelihood function may have been simplified by means of a partial specification of the model, as is the case when composite likelihood is used. In such circumstances tests and confidence regions for the parameter of interest may be constructed using Wald type and score type statistics, defined so as to account for nuisance parameter estimation or partial specification of the likelihood. In this paper a general analytical expression for the required asymptotic covariance matrices is derived, and suggestions for obtaining Monte Carlo approximations are presented. The same matrices are involved in a rescaling adjustment of the log likelihood ratio type statistic that we propose. This adjustment restores the usual chi‐squared asymptotic distribution, which is generally invalid after the simplifications considered. The practical implication is that, for a wide variety of likelihoods and nuisance parameter estimates, confidence regions for the parameters of interest are readily computable from the rescaled log likelihood ratio type statistic as well as from the Wald type and score type statistics. Two examples, a measurement error model with full likelihood and a spatial correlation model with pairwise likelihood, illustrate and compare the procedures. Wald type and score type statistics may give rise to confidence regions with unsatisfactory shape in small and moderate samples. In addition to having satisfactory shape, regions based on the rescaled log likelihood ratio type statistic show empirical coverage in reasonable agreement with nominal confidence levels.  相似文献   
33.
Abstract

In this paper, we aim at understanding the role of collaboration experience in supply chains of knowledge (SCoK). The SCoK of a company is its supply chain not related to the flow of physical goods but to the flow of R&D commodities. R&D commodities are for example patents, technologies, research services, studies, and projects, and, in high-tech industries, their development and commercialisation are considered as important as real products. To accomplish our aim in this paper, we fulfil the following research objectives: (1) investigate the relationship between the collaboration experience in SCoK and the propensity of the firm to develop new patents; (2) examine how the structural embeddedness of the firm within its SCoK mediates this relationship. We ground our conceptual model on the supply chain, open innovation and social capital literatures and empirically test our hypotheses on a cross-sectional data-set of 208 biotech companies that have signed 612 SCoK agreements in the years 2006–2010. The key findings of this study are: first, accumulating experience in SCoK collaborations facilitates the development of new patents; second, being central and bridging structural holes within the SCoK are two means by which the experience in SCoK collaborations is translated into new patents.  相似文献   
34.
Propensity score methods are an increasingly popular technique for causal inference. To estimate propensity scores, we must model the distribution of the treatment indicator given a vector of covariates. Much work has been done in the case where the covariates are fully observed. Unfortunately, many large scale and complex surveys, such as longitudinal surveys, suffer from missing covariate values. In this paper, we compare three different approaches and their underlying assumptions of handling missing background data in the estimation and use of propensity scores: a complete-case analysis, a pattern-mixture model based approach developed by Rosenbaum and Rubin (J Am Stat Assoc79:516–524, 1984), and a multiple imputation approach. We apply these methods to assess the impact of childbearing events on individuals’ wellbeing in Indonesia, using a sample of women from the Indonesia Family Life Survey. I am grateful to all the participants at the project “Poverty Dynamics and Fertility in Developing Countries” for their support and encouragement. Special thanks are due to Fabrizia Mealli for her insightful suggestions and discussions. I also thank Jungho Kim, who is the main author of the STATA code to produce Indonesia consumption expenditure. Finally, I thank Arnstein Aassve, and Letizia Mencarini for help working with the data and their very useful discussions, and Alexia Fuernkranz-Prskawetz, and Henriette Engelhardt for detailed comments and suggestions which have improved the paper. Financial support from CNR-EFS and COFIN 2005 is gratefully acknowledged.  相似文献   
35.
We analyse the Italian labour market, which is typically considered to be highly regulated. We focus on the costs imposed on firms by the institutional environment in which they operate, and on the adjustment strategies that they pursue as a result. We have followed two complementary approaches: the analysis of the development of the laws relating to hiring and firing, together with a set of interviews of 61 manufacturing firms. This also allows us to quantify the extent of turnover costs on the total labour costs. Hiring costs, which include recruiting and training, range between 2.0 and 2.6 months of labour costs; firing costs range from less than half a monthly labour cost to 20 months of labour costs in cases of conflict.  相似文献   
36.
The paper analyses the impact of foreign workers on the Italian labour market. We address the issue of whether immigrants from less developed countries are complementary or substitutes to domestic workers. We construct a data set on immigrant workers from the Administrative Social Security Archive which starts in 1986, before the general amnesty of 1990–91, when a large share of illegal immigrants were granted working permits, and end in 1995. A two-stage procedure devised by Moulton is applied to yearly cross-sections of wages by industry and region. Our results show that the inflow of immigrants raises the wages of native manual workers (i.e. it has a complementary effect), and this effect is larger in small firms and in the north of the country. We postulate that the positive impact on native wages is due to the existence of labour constraints on the side of firms. Firms are unable to expand their output because they cannot find native workers who are willing to undertake certain (typically low-skilled) jobs. Immigrants help to fill this gap. This view is reinforced by the fact that over a ‘crucial threshold’ of the share of foreign work (7.7–12 percent) additional inflows in the labour market of foreign work have a negative effect on native wages (i.e. they compete with natives).  相似文献   
37.
Social Indicators Research - The presence of foreigners in a host country is a contentious issue: opponents claim, among other things, that the cultural distance between them and natives is too...  相似文献   
38.
The paper explores patterns of skilled labour mobility from the Southern eurozone to the metropolitan area of Copenhagen by means of a qualitative micro-study. The key hypothesis is that in/outflows may not only be a consequence of the present economic crisis but may also rely on the deep-rooted, democratic-socio-cultural aspects or dissimilar policy choices of sending/hosting countries. These same aspects are expected to influence return/circular migration. In contrast to mainstream theories of international migration, this viewpoint is supported by findings which illustrate how non-economic factors can be also crucial and why enhancing beneficial return/circular migration in the Southern eurozone can be incompatible with the application of austerity.  相似文献   
39.

Quality assessment is a crucial issue in the strategic management of the public health sector. The objective of this study is to investigate the patients’ perception of the health system quality and explore the relationships between doctors and long-term cancer patients. The data under study have been collected during a survey conducted with long-term cancer patients who follow an oncological therapy in a Public Hospital. In the study, exploratory factorial analysis is developed and two structural equation models are proposed. The first model describes the service quality as perceived by the patients, which is influenced by four important factors, namely tangible aspects, reliability, empathy (doctor–patient human relations) and hospital organization. The second model describes the relationship between doctors and long-term cancer patients, which is influenced by three factors, that is reliability, empathy and hospital organization. The discussion highlights the contribution that the results of the study may make to the investigation of the possible strategies for improving health care service quality.

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40.
According to the 'reproductive polarization' hypothesis, family-policy regimes unfavourable to the combination of employment with motherhood generate greater socio-economic differentials in fertility than other regimes. This hypothesis has been tested mainly for 'liberal' Anglo-American regimes. To investigate the effects elsewhere, we compared education differentials in age at first birth among native-born women of 1950s and 1960s birth cohorts in seven countries representing three regime types. Women with low educational attainment have continued to have first births early, not only in Britain and the USA but also in Greece, Italy, and Spain. Women at all other levels of education have experienced a shift towards later first births, a shift that has been largest in Southern Europe. Unlike the educationally heterogeneous changes in age pattern at first birth seen under the Southern European and Anglo-American family-policy regimes, the changes across birth cohorts in the study's two 'universalistic' countries, Norway and France, have been educationally homogeneous.  相似文献   
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