全文获取类型
收费全文 | 1991篇 |
免费 | 143篇 |
国内免费 | 23篇 |
专业分类
财政金融 | 159篇 |
工业经济 | 142篇 |
计划管理 | 614篇 |
经济学 | 324篇 |
综合类 | 165篇 |
运输经济 | 33篇 |
旅游经济 | 35篇 |
贸易经济 | 379篇 |
农业经济 | 131篇 |
经济概况 | 175篇 |
出版年
2024年 | 5篇 |
2023年 | 41篇 |
2022年 | 23篇 |
2021年 | 67篇 |
2020年 | 69篇 |
2019年 | 73篇 |
2018年 | 67篇 |
2017年 | 73篇 |
2016年 | 64篇 |
2015年 | 81篇 |
2014年 | 162篇 |
2013年 | 248篇 |
2012年 | 146篇 |
2011年 | 176篇 |
2010年 | 140篇 |
2009年 | 96篇 |
2008年 | 104篇 |
2007年 | 91篇 |
2006年 | 94篇 |
2005年 | 59篇 |
2004年 | 41篇 |
2003年 | 53篇 |
2002年 | 23篇 |
2001年 | 35篇 |
2000年 | 33篇 |
1999年 | 19篇 |
1998年 | 19篇 |
1997年 | 10篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
排序方式: 共有2157条查询结果,搜索用时 15 毫秒
51.
Kit Pong Wong 《Bulletin of economic research》2015,67(4):371-381
This paper examines the behaviour of a competitive exporting firm under joint revenue and exchange rate risk. The firm can trade unbiased currency futures contracts for hedging purposes. We show that neither the separation theorem nor the full‐hedging theorem holds when the revenue shock prevails. If the correlation between the revenue shock and the random spot exchange rate is non‐positive, the firm optimally produces less than the benchmark level when the revenue shock is absent. If, in addition, the firm is prudent, the optimal futures position is an under‐hedge. Finally, we derive sufficient conditions under which the firm's optimal output level is higher in the presence than in the absence of the revenue shock. Operational hedging and financial hedging as such interact in a complicated way to better cope with the multiple sources of uncertainty faced by the firm. 相似文献
52.
Amber Salter Nina Thomas Tuula Tyry Gary Cutter Ruth Ann Marrie 《Journal of medical economics》2017,20(5):493-502
Aims: To better understand the impact of the clinical course of multiple sclerosis (MS) and disability on employment, absenteeism, and related factors.Materials and methods: This study included respondents to the North American Research Committee on Multiple Sclerosis Registry spring 2015 update survey who were US or Canadian residents, aged 18–65 years and reported having relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), or primary progressive MS (PPMS). The RRMS and SPMS participants were combined to form the relapsing-onset MS (RMS) group and compared with the PPMS group regarding employment status, absenteeism, and disability. Multivariable logistic regression was used to examine the relationship between employment-related outcomes and factors that may affect these relationships.Results: Of the 8004 survey respondents, 5887 (73.6%) were 18–65 years of age. The PPMS group (n?=?344) had a higher proportion of males and older mean age at the time of the survey and at time of diagnosis than the RMS group (n?=?4829). Female sex, age, age at diagnosis, cognitive and hand function impairment, fatigue, higher disability levels, ≥3 comorbidities, and a diagnosis of PPMS were associated with not working. After adjustment for disability, the employed PPMS sub-group reported similar levels of absenteeism to the employed RMS sub-group.Limitations: Limitations of the study include self-report of information and the possibility that participants may not fully represent the working-age MS population.Conclusions: In MS, employment status and absenteeism are negatively affected by disability, cognitive impairment, and fatigue. These findings underscore the need for therapies that prevent disability progression and other symptoms that negatively affect productivity in persons with MS to enable them to persist in the workforce. 相似文献
53.
高等职业技术学院中外合作办学的学生入学分数低、基础差、学习动力不足,学习英语的态度、方法等都存在一些问题.任务型教学法强调学习者通过使用目的语进行交互活动,进而掌握语言交流的实际能力.“任务型教学”的运用和实践将对外语教学模式的转变、学生语言运用能力的培养以及学习者“互动式”学习方式的形成起到积极而有益的促进作用. 相似文献
54.
55.
Measuring Farm and Market Level Economic Impacts of Improved Maize Production Technologies in Ethiopia: Evidence from Panel Data 总被引:1,自引:0,他引:1 下载免费PDF全文
Menale Kassie Paswel Marenya Yohannis Tessema Moti Jaleta Di Zeng Olaf Erenstein Dil Rahut 《Journal of Agricultural Economics》2018,69(1):76-95
While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels. 相似文献
56.
Kathleen Mary Noon Stephen Maxwell Montgomery Nicholas Edward Adlard 《Journal of medical economics》2018,21(10):983-992
Objectives: Specific economic model types often become de facto standard for health technology appraisal over time. Markov and discrete event simulation (DES) models were compared to investigate the impact of innovative modeling on the cost-effectiveness of disease-modifying therapies (DMTs) in relapsing–remitting multiple sclerosis (RRMS). Fingolimod was compared to dimethyl fumarate (DMF; in highly active [HA] RRMS), alemtuzumab (in HA RRMS) and natalizumab (in rapidly evolving severe RRMS). Comparator DMTs were chosen to reflect different dosing regimens.Materials and methods: Markov and DES models used have been published previously. Inputs were aligned in all relevant respects, with differences in the modeling of event-triggered attributes, such as relapse-related retreatment, which is inherently difficult with a memoryless Markov approach. Outcomes were compared, with and without different attributes.Results: All results used list prices. For fingolimod and DMF, incremental cost-effectiveness ratios (ICERs) were comparable (Markov: £4206/quality-adjusted life year [QALY] gained versus DES: £3910/QALY gained). Deviations were observed when long-term adverse events (AEs) were incorporated in the DES (Markov: £25,412 saved/QALY lost, versus DES: £34,209 saved/QALY lost, fingolimod versus natalizumab; higher ICERs indicate greater cost-effectiveness). For fingolimod versus alemtuzumab, when relapse-triggered retreatment was included in the DES, large cost differences were observed (difference between incremental cost is £35,410 and QALY is 0.10).Limitations: UK payer perspective, therefore societal approach was not considered. Resource utilization and utilities for both models were not derived from the subpopulations; as the focus is on model type, input limitations that apply to both models are less relevant.Conclusions: Whilst no model can fully represent a disease, a DES allows an opportunity to include features excluded in a Markov structure. A DES may be more suitable for modeling in RRMS for health technology assessment purposes given the complexity of some DMTs. This analysis highlights the capabilities of different model structures to model event-triggered attributes. 相似文献
57.
肖海越 《中国农业资源与区划》2016,37(8):180-185
作为提高农业生产效率、改善农民生活质量及促进农村经济增长的重要物质基础,农村基础设施建设对扩大农村地区内需增长点,解决农村剩余劳动力就业问题以及全面推进城乡统筹发展具有至关重要的意义。广东省作为我国南部地区经济发达省份,具有丰富的农业生产自然资源,但其农村基础设施发展程度相对来说却比较低,其成为农村经济发展的"瓶颈",不利于农村经济结构优化升级。为了保障农村基础设施的供给与农村经济发展水平保持协调一致,文章以广东地区农村为例,采用多元非线性回归分析的方法,在论证农村基础设施建设对农村经济增长的作用机制的基础上,从农村基础设施建设与农业生产、非农生产和农民人均纯收入3方面的内在关系进行计量分析,结果表明,首先农村基础设施对影响农业经济增长的3方面因素都发挥了显著的规模经济效益;其次农村基础设施建设中的教育变量对农业经济增长的作用最为显著;再次,农业机械设施在农业生产中的作用相对于其他影响因素而言不太显著;最后,道路、通讯设施对非农生产和农民人均收入收入的贡献率相对其他变量数值较低。并提出健全农村基础设施建设投融资机制、加大农村基础设施的资金投入力度、提高农村基础设施建设和利用水平、全面推进农村基础设施建设进程等优化策略。 相似文献
58.
Morris Altman 《Forum for Social Economics》2017,46(3):234-251
In the conventional economic wisdom, the notion of unique equilibria that are efficient and Pareto optimal dominates the modeling discourse. Hebert Simon proposed an alternative analytical framework where the notion of multiple and sustainable equilibria is critical. Multiple equilibrium is the crucial stylized fact of economic life that requires better understanding and modeling. Of particular significance, Simon touched on the importance of institutions and differential power relationships in affecting economic outcomes. But this modeling approach was not well developed by Simon. Following from his contributions, further develop the notion of multiple equilibria especially in the realm of production with an emphasis on x-efficiency theory. I bring to bear the importance of institutional parameters (including power relationships), culture, norms, ethics, and moral sentiments to the determination of economic outcomes. In the model developed here, boundedly rational decision-makers’ choices are contextualized and constrained by complex environmental factors. No one choice is either inevitable or economically efficient. A multiplicity of outcomes is possible and sustainable inclusive of those that are suboptimal. Much depends on individual preferences and institutional design. This has significant implication for institutional design and policy. 相似文献
59.
利用辐射源目标的频移动态特征进行盲分选时,针对已有的分选方法不能很好解决非合作接收数据非周期、间断、交叠的问题,提出了一种改进的逻辑回归分选算法,将信号分选转化为轨迹分类的问题来处理。首先,借鉴多目标航迹起始模型中的M/N逻辑法的框架,设计新的数据关联门限,以建立目标起始曲线;其次,采用最小二乘拟合方法替代卡尔曼滤波,设计新的外推规则,建立载频变化预测曲线;分析新的接收数据与预测曲线的关联性,不断迭代回归或形成新的分支,最后获得目标分选结果。仿真与实测试验表明,利用逻辑回归分选算法,对不同运动目标搭载的同频辐射源可进行自动分选,4个仿真目标与2个真实目标的分选正确率达到100%。同时,该方法拓展了辐射源目标盲分选中的动态频移特征应用,为辐射源个体识别提供了新的支持。 相似文献
60.
Agricultural applications of nanotechnology are at a relatively early stage and little is known about consumer responses to the technology. Canadian consumer responses to food nanotechnology are examined through the lens of the Food Value Scale. Data from a survey of Canadian consumers are used to evaluate the relative importance of eleven food values to food purchase decisions. We find that taste, safety, nutrition, and price are among the most important food values to Canadians, however, consumers exhibit considerable heterogeneity with respect to the priority placed on these values. A discrete choice experiment (DCE) explores the effect of food values on choice behavior. The DCE is positioned as a sliced apple product with non-browning and antioxidant-enhanced features introduced through the use of nanocoating or a conventional coating method. Random parameters logit (RPL) and latent class models (LCM) confirm the existence of significant preference heterogeneity. The LCM identifies three classes of consumers: “supporters,” “doubters,” and “opponents” who differ in their reaction to nanotechnology and in the relative importance placed on food values such as naturalness, novelty, and convenience. The analysis shows that food values provide additional insights into consumers’ food choices and their attitudes toward novel food technologies. 相似文献