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1.
This paper evaluates economic impacts arising from the introduction of high-speed rail (HSR) between Madrid and Barcelona. Using difference-in-differences estimation we estimate an average treatment effect for provinces with stops on the HSR line of 2.4% for economic output, 3.3% for numbers of firms, and 1.1% for labour productivity. We complement our DID results with a synthetic control analysis for Lleida and Tarragona, two provinces that we argue were assigned HSR stations largely due to their incidental location. We find that both the number of firms and labour productivity are substantially higher in these provinces than in their synthetic counterparts.  相似文献   
2.
The United States is entering a new era, a period marked by some important demographic changes in the composition of the population, most especially significant increases in the Latino and Latino immigrant segments of society. These population shifts require corresponding interpersonal, organizational, and structural changes. The present issue bridges research and theory across disciplines and includes studies incorporating a variety of methodologies to examine these important areas. These articles begin to fill some of the voids where a systematic and robust corpus of knowledge is lacking. The contributions address topics ranging from issues of identity and interpersonal relations to pressing matters of educational significance to general approaches to navigating the cultural transitions that mark fluid transnational adaptations. Finally, each contribution delineates the policy implications resulting from the processes and literatures that are examined.  相似文献   
3.
Some popular parametric diffusion processes have been assumed as such underlying diffusion processes. This paper considers an important case where both the drift and volatility functions of the underlying diffusion process are unknown functions of the underlying process, and then proposes using two novel testing procedures for the parametric specification of both the drift and diffusion functions. The finite-sample properties of the proposed tests are assessed through using data generated from four popular parametric models. In our implementation, we suggest using a simulated critical value for each case in addition to the use of an asymptotic critical value. Our detailed studies show that there is little size distortion when using a simulated critical value while the proposed tests have some size distortions when using an asymptotic critical value in each case.  相似文献   
4.
This paper draws on an empirical study of stigma and child welfare services in the United Kingdom, the Netherlands, and Spain. It focuses exclusively on the findings relating to the United Kingdom and shows how stigma continues to be a part of the experience of using and delivering child welfare services, despite the positive determination of policies that this should not be so. More optimistically, however, it is also evident that the experience of stigma and exclusion can be reduced, and the paper concludes by outlining the implications for policy and practice together with those factors which would appear to be most significant in combating stigma.  相似文献   
5.
Survey calibration methods modify minimally sample weights to satisfy domain-level benchmark constraints (BC), e.g. census totals. This allows exploitation of auxiliary information to improve the representativeness of sample data (addressing coverage limitations, non-response) and the quality of sample-based estimates of population parameters. Calibration methods may fail with samples presenting small/zero counts for some benchmark groups or when range restrictions (RR), such as positivity, are imposed to avoid unrealistic or extreme weights. User-defined modifications of BC/RR performed after encountering non-convergence allow little control on the solution, and penalisation approaches modelling infeasibility may not guarantee convergence. Paradoxically, this has led to underuse in calibration of highly disaggregated information, when available. We present an always-convergent flexible two-step global optimisation (GO) survey calibration approach. The feasibility of the calibration problem is assessed, and automatically controlled minimum errors in BC or changes in RR are allowed to guarantee convergence in advance, while preserving the good properties of calibration estimators. Modelling alternatives under different scenarios using various error/change and distance measures are formulated and discussed. The GO approach is validated by calibrating the weights of the 2012 Health Survey for England to a fine age–gender–region cross-tabulation (378 counts) from the 2011 Census in England and Wales.  相似文献   
6.
7.
This study examined whether cognitive control mediated the association between socioeconomic status (SES; composite of income‐to‐needs ratio and parent education) and changes in risk‐taking behaviors. The sample included 167 dyads of adolescents (53% male; Mage = 14.07 years at Time 1) and their parents, assessed annually across 4 years. Parents reported socioeconomic variables at Time 1. Adolescents reported risk‐taking behaviors at Times 1 and 4, and completed a functional magnetic resonance imaging cognitive control task at Times 2 and 3. Lower SES was associated with lower behavioral (but not neural) cognitive control, which was associated with increases in risk‐taking behaviors. The findings suggest that elevated socioeconomic risk may compromise cognitive control which can cascade into maladaptive behaviors in adolescence.  相似文献   
8.
Ferran Pons  Laura Bosch 《Infancy》2010,15(3):223-245
As a result of exposure, infants acquire biases that conform to the rhythmic properties of their native language. Previous lexical stress preference studies have shown that English‐ and German‐, but not French‐learning infants, show a bias toward trochaic words. The present study explores Spanish‐learning infants' lexical stress preferential patterns and the role of syllable weight at 9 months of age. Spanish is a syllable‐timed language with no vowel reduction and variable stress. Around 50% of the word types in Spanish are disyllabic, with a superior proportion of trochees than iambs (60% and 40%, respectively). Experiment 1 with CV.CV pseudo‐words failed to reveal a clear trochaic bias in 9‐month‐old Spanish‐learning infants. However, when preference was explored with items containing a heavy syllable (CVC.CV and CV.CVC, respectively), both a trochaic (Experiment 2) and an iambic preference (Experiment 3) could be elicited. These results suggest that knowledge about the close and highly regular link between heavy syllables and stress assignment in Spanish can be easily acquired and determines infants' preference at 9 months of age, while for CV.CV items, the trochaic bias appears to be weak. Our results broaden the current knowledge on the factors that determine the emergence of rhythmic biases.  相似文献   
9.
Some popular parametric diffusion processes have been assumed as such underlying diffusion processes. This paper considers an important case where both the drift and volatility functions of the underlying diffusion process are unknown functions of the underlying process, and then proposes using two novel testing procedures for the parametric specification of both the drift and diffusion functions. The finite-sample properties of the proposed tests are assessed through using data generated from four popular parametric models. In our implementation, we suggest using a simulated critical value for each case in addition to the use of an asymptotic critical value. Our detailed studies show that there is little size distortion when using a simulated critical value while the proposed tests have some size distortions when using an asymptotic critical value in each case.  相似文献   
10.
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