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131.
In this article, I derive the Lagrange multiplier test of the null hypothesis that a stationary random vector has a (possibly heteroscedastic) normal distribution against the alternative that the distribution is a member of the family with seminonparametric probability density functions considered by Gallant and Tauchen (1989). The test is shown to contain special cases of the moment tests proposed by Newey (1985) and Tauchen (1985). Evidence from a small simulation study is reported, showing that the test has reasonable finite-sample properties in moderately sized samples. The test is applied to the change of price in a treasury-bill data series analyzed by Tauchen and Pitts (1983) and Tauchen (1985).  相似文献   
132.
Early cities depended on local, solar-based energy resources for their metabolism. Over time, cities have become increasingly dependent on fossil fuels, both directly and indirectly, as they facilitate exploitation of solar resources from much farther away. Alternatives to fossil fuels, typically generated locally, often provide lower surplus energy to society. As cities consider the transition back to solar-based energy resources, it becomes necessary to understand the capability of the solar-based economy to provide e.g. energy (including food) from nearby lands. To do so, we compared the energy metabolism (respiration) of a typical rust-belt city, Syracuse, NY, with the net primary production in the surrounding county (production) over its development (1840–2005). We calculated the ratio of respiration to production (R:P) and examined how this ratio changed during the periods of industrialization, shifts in major fuel types, and deindustrialization. We found that from 1840 to 1950 respiration became increasingly centralized in the urban core; since then it has become more diffused. Urban respiration exceeded production in the county by 9:1 in 1930, and it remains just under 2:1 today. Respiration reached an absolute (67 PJ) and a per capita (339 GJ) maximum in 1970, then fell by 40 % and 20 % respectively, due to deindustrialization and population losses. Conversely, production increased 480 % from its lows in 1930 because of reforestation and improved agricultural yields. What this means is that to achieve a higher P:R ratio requires either increased production of food and fuels in areas surrounding the city, or decreased per capita energy consumption.  相似文献   
133.
Abstract Within the political economy of agriculture and agrofood literatures there are examples of approaches that reject simple dichotomies between alternatives and the mainstream. In line with such approaches, we challenge the assumption that alternative agriculture, and its attendant improved environmental practices, alternative management styles, less intensive approaches, and better approaches to animal and ecosystem welfare, is the only source of agricultural sustainability. This article uses national farm‐survey results for New Zealand's sheep and beef, dairy, and horticulture sectors to examine conventional farmers, measure their assessments of farming practices, and assess their environmental orientation. Analysis identifies a proenvironmental cluster of farmers in each sector characterized by a higher environmental‐orientation score and distinct ratings of other farm practices queried in the survey. We interpret the results in terms of the exposure of different agricultural sectors to the effects of market‐based, audited, best‐practice schemes. The presence of shades of “greenness” among conventional farmers has important implications for environmental management and for our understanding of the various and complex pathways toward the greening of agrofood systems.  相似文献   
134.
A common assumption for data analysis in functional magnetic resonance imaging is that the response signal can be modelled as the convolution of a haemodynamic response (HDR) kernel with a stimulus reference function. Early approaches modelled spatially constant HDR kernels, but more recently spatially varying models have been proposed. However, convolution limits the flexibility of these models and their ability to capture spatial variation. Here, a range of (nonlinear) parametric curves are fitted by least squares minimisation directly to individual voxel HDRs (i.e., without using convolution). A ‘constrained gamma curve’ is proposed as an efficient form for fitting the HDR at each individual voxel. This curve allows for spatial variation in the delay of the HDR, but places a global constraint on the temporal spread. The approach of directly fitting individual parameters of HDR shape is demonstrated to lead to an improved fit of response estimates.  相似文献   
135.
This paper examines the framing of crisis communication strategies before, during, and after Hurricanes Katrina and Rita by analyzing news releases from the Federal Emergency Management Agency, Homeland Security, and U.S. Senators and Governors from Mississippi, Louisiana, and Texas. A qualitative content analysis found that all entities analyzed did not acknowledge their parts in the crises, placed blame on others, and tried to distance themselves from the crises. State leadership also used a unifying approach where they included themselves in the hardships affected residents were experiencing.  相似文献   
136.
Funding for care service research is increasingly subject to the satisfaction of two requirements: public involvement and adoption of validated outcome tools. This study identifies competing paradigms within these requirements and reveals significant challenges faced by researchers who seek to satisfy them. The focus here is on a study co‐produced between academic researchers and people with experience of adult social care services. It examines to what extent research studies can conduct high‐quality public involvement and genuine co‐production of knowledge, whilst attempting to produce quantifiable outcome scores. Findings add to debate around how to incorporate diverse perspectives in research, which may draw on incommensurate accounts of validity and reliability. Findings also highlight constructive attempts by academic and co‐researchers to make the combination of approaches work in the field. These small scale acts of researcher agency indicate some scope to combine the two approaches in future research studies. However, conclusions foreground the importance of broader awareness of how tensions and power imbalances related to this combination of approaches play out in social policy research practice.  相似文献   
137.
It has long been recognised that the balance between backward-looking and forward-looking expectations has critical policy implications. This is because backward-looking expectations impart a substantial degree of inertia to the inflation rate whereas forward-looking expectations lead to rapid adjustment in response to shocks. In this paper we examine the policy implications for the Indonesian economy of the form taken by the price adjustment equation. We allow for both backward-looking and forward-looking effects of inflation expectations, proxying forward expectations with the realised rate and using a GMM estimator to allow for the resulting endogeneity. Using monthly data from 1980:1 to 2008:12, our estimates show that CPI inflation in Indonesia is significantly determined by backward-looking inflation expectations, forward-looking inflation expectations, the output gap, exchange rate depreciation, and money growth. However, the backward expectation attracts a significantly higher weight than the forward rate leading to the conclusion that inflation in Indonesia has considerable inertia. The implication of this is that a gradualist monetary policy is likely to be more effective as a means of smoothing fluctuations in inflation and real output.  相似文献   
138.
139.
Over the past 20 years, the US Federal Government has been considered to be intransigent in its response to climate change by many commentators and not-for-profit environmental advocacy organizations (nonprofits). An enduring source of pressure on the US Government has been nonprofit campaigns operating at both a state and federal level. Six US environmental nonprofits representing a diversity of resources and prominence were selected for an in-depth examination of their climate-focused campaigns. Given the resistance at the federal level, these nonprofits have undertaken state-focused campaigns to achieve adequate climate policy development. This research examined some climate campaigns in California by the selected nonprofits that have supported, enhanced, and influenced the Californian Government’s efforts to address climate change. The campaigns have gained leverage from existing state competition for economic advancement and political leadership on issues of public concern. In addition, they appear to have benefited from a high level of environmental awareness in the community, a history of progressive environmental legislation, Governor Schwarzenegger’s use of climate change to differentiate his political leadership, and strong public trust of nonprofits. Recent climate-related political pledges and legislative changes at a federal level are convergent with the nonprofit-influenced, state-level developments.  相似文献   
140.
This essay discusses neo-liberalism as a hegemonic process, offering an interpretation of the past 40 years of British political developments.  相似文献   
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