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991.
Behavioural adaptations are recognized as crucial determinants for successful establishment and persistence of animal populations in a novel urban environment. Here, we examined mechanisms responsible for the development of urban behavioural type in a common waterbird, the Eurasian coot Fulica atra. We compared the behaviour of coots from a rural population and two urban populations that differed in the timing of colonization event (1960s vs. 2000s). We found that some behavioural characters associated with urban life (aggression during nest defence and boldness towards humans during foraging) were more strongly expressed in the older urban population when compared with the recently established urban population. By contrast, coots from the two urban populations showed a similar likelihood of exploiting human-derived food resources, as well as they showed similar levels of physiological stress. Urban coots were generally more aggressive, bolder, and less stressed than their rural conspecifics. Large behavioural and physiological divergence of coots from the recently established urban population and their rural conspecifics suggested that phenotypic plasticity and phenotype sorting may play a key role in the initial stages of urban colonization. On the other hand, increasing expression of boldness and aggression with the time since urbanization may suggest the role of microevolutionary adaptation in response to novel selective forces associated with the urban environment. Our results indicate that a combination of different processes (phenotypic plasticity, phenotype sorting, and microevolution) can determine successful colonization of urban areas by the Eurasian coots, and possibly other bird species.  相似文献   
992.
In this paper, we re-analyze data from a large-scale field experiment (N = 344,084) on voter turnout in order to determine whether men and women respond differently to social pressure aimed at voter mobilization. To date, there have been mixed results regarding the interaction between a person’s gender and receptivity to social influence. On the whole, our analyses confirm prior findings that social pressure increases voter turnout but uncover little to no evidence of gender differences in receptivity to social pressure cues in the context of political participation.  相似文献   
993.
This paper examines the short and medium term impact of early childcare provision by grandparents and formal care settings on child cognitive outcomes, using data from the Millennium Cohort Study (UK). Compared with children placed in formal childcare, children cared for by their grandparents are better at naming objects, but perform worse on tests of basic concept development and non-verbal reasoning. These results mask strong heterogeneities. On the one hand, the positive association between grandparental care and child outcomes is stronger for children from more advantaged households; on the other, the negative association is only significant for those from more disadvantaged households. The results of OLS estimations used for our analysis are confirmed using panel methods and an instrumental variable approach.  相似文献   
994.
In response to a low fertility rate, a number of municipalities in South Korea have been providing family benefits in the form of childbirth grants and child allowances. Using panel data for 230 municipalities that spans the years 2001–2014, this paper examines the impacts of family benefits on the fertility rate in Korea. I use the fact that different municipalities began providing the family benefits at different times to estimate the impact of family benefits on fertility rates using a difference-in-differences approach. This study finds a positive effect of family benefits on total fertility rate. Moreover, it finds little evidence of an anticipatory response within municipalities that adopted the policy. Given that a 10 million Korean won increase in family benefits is associated with a 3.5% increase in the total fertility rate, an increase in family benefits of about 44 million Korean won per child would be required to raise the total fertility rate to a safe zone above 1.5 children per woman, where population declines are gradual and easily reversed.  相似文献   
995.
This research uses nationally representative data to study how economic resources and inequalities are associated with life satisfaction of Chinese residents. We construct economic resource and inequality measures from expenditure rather than from income, after confirming that expenditure inequality is a better measure in the Chinese context. We find that economic inequalities in general are negatively associated with life satisfaction, and that this association is larger for inequalities in the lower half of the distribution than those in the upper half of the distribution. We further explore the mechanisms under which inequality can be associated with life satisfaction, and find that aspiration is potentially one important channel.  相似文献   
996.
The aim of this paper is to empirically study the effect of uncertainty on private consumption using a sample of Spanish households, and therefore, to test the existence of a precautionary motive for saving. Using data provided by the Spanish Survey of Household Finances and the Labour Force Survey we construct several uncertainty measures that are commonly used in the literature and an additional indicator based on job insecurity data, and we consequently estimate different econometric models under the life-cycle/permanent income hypothesis, including these measures of uncertainty. Our results are twofold: first, we find evidence in favour of the precautionary saving hypothesis. Secondly, we find that, unlike other variables related to the performance of the labour market (such as the unemployment rate) the job insecurity indicator is an appropriate variable to approximate income uncertainty in any macroeconomic context.  相似文献   
997.
Personal wealth has grown since the 1970s twice as fast in real terms as national income. Has this rise in the wealth-income ratio led to a corresponding increase in the wealth being passed on from one generation to the next? Are we returning to the levels of inheritance found in the 19th century? The aim of this paper is to construct UK evidence on the extent of the transmission of wealth in the form of estates and gifts inter vivos. It takes a long-run view of inheritance, starting from 1896, when the modern Estate Duty was introduced, and exploits the extensive estate data published over the years. Construction of a long-run time series for more than a century is challenging, and there are important limitations. The resulting time-series demonstrates the major importance of inheritance in the UK before the First World War, when the total transmitted wealth represented some 20 per cent of net national income. In the inter-war period, the total was around 15 per cent, falling to some 10 per cent after the Second World War, and then falling further to below 5 per cent in the late 1970s. Since then, there has indeed been an upturn: a rise from 4.8 per cent in 1977 to 8.2 per cent in 2006. This increase was more or less in line with the increase in personal wealth, and has to be interpreted in the light of the changing net worth of the corporate and public sectors of the economy.  相似文献   
998.
This paper examines the response of income concentration in the US to the occurrence of major systemic banking crises since the beginning of the twentieth century. In doing so, the paper analyzes the shape of the upper income tail as well as the national income shares accruing to different groups within the richest decile. The findings suggest that systemic banking crises reduce income concentration within the top decile of the US pre–tax and transfers income distribution, and more generally, that the effect is highly heterogeneous across different top income groups. While the richest income group loses ground, the lower half of the top decile appears to gain in relative terms. However, evidence suggests that the estimated short-term effect of market forces stemming from banking crises can be relatively small in magnitude and even temporary in nature, as it may be quickly reabsorbed. These findings lend indirect support to the idea that only substantial changes in government policies and institutional frameworks can bring about radical changes in income distribution.  相似文献   
999.
We examine how the recession that started in December 2007 in the United States impacted wealth accumulation and inequality among Spanish households. We find that overall wealth dropped by 15 percent between 2008 and 2011, with losses concentrating among households in the mid and top wealth quintiles. The most hard hit wealth components were business assets, primary home equity, and durable assets, which declined by 40 percent, 23 percent and 19 percent, respectively. Wealth losses among all households were likely sustained by restricted access to credit. Nonetheless, in part due to their more diversified wealth portfolios, households in the top wealth quintile amassed a greater share of the country’s wealth during the recession. Consequently, wealth inequality, which receded during the expansionary years of 2002 through 2005, rose by 2008 and continued its trend in 2011.  相似文献   
1000.
Public debates about the rise in top income shares often focus on the growing dispersion in earnings, and the soaring pay for top executives and financial-sector employees. But can the change in the marginal distribution of earnings on its own explain the rise in top income shares? Are top executives replacing capital owners in the group of top-income earners, or are we rather witnessing a fusion of top capital and top earnings? This paper proposes an extension of the copula framework and uses it for exploring the changing composition of top incomes. It illustrates that changes in top income shares can easily be decomposed into respective changes in the marginal distributions of labour and capital income and the changing association between the two types of income. An application using tax record data from Norway shows that the association between top labour and capital incomes grew stronger between 1995 and 2005 in the top half of the wage and capital income distribution, though it declined for the top 1% of capital income receivers. A gender decomposition demonstrates that the association of wage and capital incomes at the top is particularly striking for men, whilst women are largely under-represented in the top halves of the two marginal distributions.  相似文献   
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