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931.
This paper scrutinizes the conventional wisdom about trends in UK income inequality and also places contemporary inequality in a much longer historical perspective. We combine household survey and income tax data to provide better coverage of all income ranges from the bottom to the very top (and make our estimates available to other researchers). We make a case for studying distributions of income between tax units (i.e. not assuming the full income sharing that goes with the use of the household as the unit of analysis) for reasons of principle as well as data harmonization. We present evidence that income inequality in the UK is as least as high today as it was just before the start of World War 2. 相似文献
932.
In this paper, we develop a theoretical model able to capture some of the main features that govern knowledge sharing and
innovation. We pursue our target developing an agent-based model in which the social network of interactions is specified
as a knowledge resource, and knowledge integration is seen as the process by which the resource can be applied to innovation.
The results of the simulation exercises show that the initial architecture of acquaintance networks is a crucial factor for
innovation. Innovating has proven to be more than simply equating endowments of initial skills with firm performance. In fact,
the performance of the system showed high sensitivity to the arrangement of the firm’s initial location in the social network.
Moreover, the way in which acquaintance networks were mobilized emerged as a key determinant of innovation patterns. The model
presented here is a relatively theoretical, stylized model and we employ it to draw some general, albeit preliminary conclusions,
while illustrating some of the theory relevant to the issues discussed. It is argued that the model might serve the purpose
of setting an agenda for further research along this line of investigation—that is, knowledge integration patterns and firms
partnerships formation. 相似文献
933.
A simple open-economy AK model with collateral constraints accounts for growth breaks and growth-reversal episodes, during which countries face abrupt
changes in their growth rate that may lead to either growth miracles or growth disasters. Absent commitment to investment
by the borrowing country, imperfect contract enforcement leads to an informational lag such that the debt contracted upon
today depends upon the past stock of capital. The no-commitment delay originates a history effect by which the richer a country has been in the past, the more it can borrow today. For (arbitrarily) small delays,
the history effect offsets the growth benefits from international borrowing and dampens growth, and it leads to both leapfrogging
in long-run levels and growth breaks. When large enough, the history effect originates growth reversals and we connect the
latter to leapfrogging. Finally, we argue that the model accords with the reported evidence on changes in the growth rate
at break dates. We also provide examples showing that leapfrogging and growth reversals may coexist, so that currently poor
but fast-growing countries experiencing sharp growth reversals may end up, in the long-run, significantly richer than currently
rich but declining countries. 相似文献
934.
Vito A. Muscatelli Piergiovanna Natale Patrizio Tirelli 《European Journal of Political Economy》2012,28(1):14-26
We model a monetary union where fiscal discretion generates excessive debt accumulation in steady state and inefficiently delayed debt adjustment following shocks. By setting a debt target and raising the political cost of deviating from the optimal pace of debt reversal¸ institutional design induces fiscal policymakers to implement unbiased responses to shocks. This is partly achieved by increasing the transparency of the decision-making process. We therefore call for more focused supervision tasks for the European Commission and for parliamentary discussion whenever a disagreement arises between the Commission and a national government. 相似文献
935.
Contagious development: Neighbor interactions in deforestation 总被引:2,自引:0,他引:2
We estimate neighbor interactions in deforestation in Costa Rica. To address simultaneity and the presence of spatially correlated unobservables, we measure for neighbors' deforestation using the slopes of neighbors' and neighbors' neighbors' parcels. We find that neighboring deforestation significantly raises the probability of deforestation. Policies for agricultural development or forest conservation in one area will affect deforestation rates in non-targeted neighboring areas. Correct estimation of the interaction reverses the naive estimate's prediction of multiple equilibria. 相似文献
936.
James A. Roumasset 《Resource and Energy Economics》2012,34(1):112-128
Optimal sequencing of resource extraction is typically studied for nonrenewable resources. We provide conditions for optimal use of multiple sources of a renewable resource and characterize the resulting extraction sequence, resource scarcity values, and (single) efficiency price path for two groundwater aquifers and an abundant alternative resource. Even with one demand, the optimal sequence depends on the differential opportunity costs of the two renewables. A numerical simulation for the South O‘ahu aquifer system, which also allows for different distribution costs, illustrates the case of using the “leakier” aquifer first and then switching to simultaneous use of both resources. The welfare gain from specialization relative to independent management is $4.7 billion. 相似文献
937.
Lee A. Smales 《Applied economics letters》2017,24(16):1148-1153
We examine the relationship between changes in the level of investor fear (proxied by the ASX 200 implied volatility index) and Australian financial market returns. We document a statistically significant relationship, across asset classes, where returns decline as investor fear increases. Returns are more sensitive to changes in the level of investor fear during the financial crisis of 2008–2009, when investor fear spikes sharply. Taken together, the results confirm that Australian financial market returns are closely related to prevailing levels of investor fear. 相似文献
938.
A farm-level deterministic and stochastic nonparametric tests of profit maximization and cost minimization behaviour for a sample of 112 Kansas farms was completed from 1996 to 2013. Allowing for monotonic non-regressive technological change and using a 10% significance level, 73 farms violated the profit-maximization hypothesis and 58 farms violated the cost minimization hypothesis. More profit maximization violations existed relative to cost minimization violations. However, comparing these results with results for 289 Kansas farms using data from 1973 to 1990, farms have significantly reduced profit maximizing violations. Cost minimizing behaviour has not changed substantially. 相似文献
939.
Introduction Anaplastic lymphoma kinase (ALK) targeting drugs provide an important option for advanced non-small cell lung cancer patients with this distinct tumor type; however, there is considerable uncertainty as to which drug provides the optimal value after crizotinib treatment. This study estimated the cost-utility of alectinib vs ceritinib from a US payer perspective.Methods A cost-utility model was developed using partition survival methods and three health states: progression-free (PF), post-progression (PP), and death. Survival data were derived from the key clinical trials (alectinib: NP28761 &; NP28673, ceritinib: ASCEND I and II). Costs included drugs, adverse events, and supportive care. Utilities were based on trial data and the literature. One-way and probabilistic sensitivity analyses (PSA) were performed to assess parameter uncertainty.Results Treatment with alectinib vs ceritinib resulted in increases of 2.55 months in the PF state, 0.44 quality adjusted life-years (QALYs), and $13,868, yielding a mean cost/QALY of $31,180. In the PSA, alectinib had a 96% probability of being cost-effective at a willingness-to-pay of $100,000/QALY. Drivers of model results were drug costs and utilities in the PF health state. The ICER ranged from $10,600–$65,000 per QALY in scenario analyses, including a sub-group analysis limited to patients with prior chemotherapy and crizotinib treatment.Conclusions Treatment with alectinib in ALK?+?crizotinib-treated patients increased time progression-free and QALYs vs ceritinib. The marginal cost increase was driven by longer treatment durations with alectinib. This model demonstrates that alectinib may be considered a cost-effective treatment after progression on crizotinib. 相似文献
940.
Aims: Subdermal implantable buprenorphine (BSI) was recently approved to treat opioid use disorder (OUD) in clinically-stable adults. In the pivotal clinical trial, BSI was associated with a higher proportion of completely-abstinent patients (85.7% vs 71.9%; p?=?.03) vs sublingual buprenorphine (SL-BPN). Elsewhere, relapse to illicit drug use is associated with diminished treatment outcomes and increased costs. This study evaluated the cost-effectiveness of BSI vs SL-BPN from a US societal perspective.Methods: A Markov model simulated BSI and SL-BPN cohorts (clinically-stable adults) transiting through four mutually-exclusive health states for 12 months. Cohorts accumulated direct medical costs from drug acquisition/administration; treatment-diversion/abuse; newly-acquired hepatitis-C; emergency room, hospital, and rehabilitation services; and pediatric poisonings. Non-medical costs of criminality, lost wages/work-productivity, and out-of-pocket expenses were also included. Transition probabilities to a relapsed state were derived from the aforementioned trial. Other transition probabilities, costs, and health-state utilities were derived from observational studies and adjusted for trial characteristics. Outcomes included incremental cost per quality-adjusted-life-year (QALY) gained and incremental net-monetary-benefit (INMB). Uncertainty was assessed by univariate and probabilistic sensitivity analysis (PSA).Results: BSI was associated with lower total costs (?$4,386), more QALYs (+0.031), and favorable INMB at all willingness-to-pay (WTP) thresholds considered. Higher drug acquisition costs for BSI (+$6,492) were outpaced, primarily by reductions in emergency room/hospital utilization (?$8,040) and criminality (?$1,212). BSI was cost-effective in 89% of PSA model replicates, and had a significantly higher NMB at $50,000/QALY ($20,783 vs $15,007; p?.05).Conclusions: BSI was preferred over SL-BPN from a health-economic perspective for treatment of OUD in clinically-stable adults. These findings should be interpreted carefully, due to some relationships having been modeled from inputs derived from multiple sources, and would benefit from comparison with outcomes from studies that employ administrative claims data or a naturalistic comparative design. 相似文献