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821.
Statistical Thinking in Empirical Enquiry   总被引:4,自引:0,他引:4  
This paper discusses the thought processes involved in statistical problem solving in the broad sense from problem formulation to conclusions. It draws on the literature and in-depth interviews with statistics students and practising statisticians aimed at uncovering their statistical reasoning processes. From these interviews, a four-dimensional framework has been identified for statistical thinking in empirical enquiry. It includes an investigative cycle, an interrogative cycle, types of thinking and dispositions. We have begun to characterise these processes through models that can be used as a basis for thinking tools or frameworks for the enhancement of problem-solving. Tools of this form would complement the mathematical models used in analysis and address areas of the process of statistical investigation that the mathematical models do not, particularly areas requiring the synthesis of problem-contextual and statistical understanding. The central element of published definitions of statistical thinking is "variation". We further discuss the role of variation in the statistical conception of real-world problems, including the search for causes.  相似文献   
822.
We examine the exports versus foreign direct investment (FDI) decision under demand uncertainty for an asymmetric cost duopoly. One of the firms can lead entry before demand realization or retain flexibility enjoying an informational advantage. When the time value of information is small and for sufficiently low investment costs, follow‐the‐leader behavior in FDI arises. Relatively high investment (fixed) costs result in follow‐the‐leader exporting behavior. When the time value of information becomes significant, the potential leader will opt for a wait‐and‐see strategy. For intermediate values of investment costs, the efficient firm invests, while the rival chooses to export.  相似文献   
823.
Alternative land management practices, including agroforestry, help to maintain levels of soil organic matter (SOM) and can facilitate soil carbon (C) sequestration for mitigating atmospheric CO2 emissions. This study quantified C inputs and determined the changes of the soil C pool in a 19-year-old Gliricidia sepium alley cropping system, studied at two fertiliser levels (tree prunings only [? N], and tree prunings plus chicken manure [+ N]), and was compared to a sole crop system. Carbon input from tree prunings ranged from 455 to 457 g C m? 2 y? 1, whereas C inputs from crop residues were similar between alley- and sole crops ranging from 121 to 159 g C m? 2y? 1. The soil organic C (SOC) pool in the alley crop was 16–23% higher than the sole crop. In the 19th year of alley farming, SOC was significantly higher (p < 0.05) in the alley crop (3.2%) compared to the sole crop (2.4%), and was also greater compared to that at the time of establishment of the agroforestry system (2.8%). Gross SOC turnover to a 20-cm depth ranged from 12 to 14 years in the + N and ?N alley crops compared to 49 and 50 years in the + N and ?N treatments for the sole crops. Residue stabilisation efficiency in the alley crops was 39% and 55% in + N and ?N treatments respectively.  相似文献   
824.
In this paper, we present estimates of the Human Development Index and the Gender-Related Development Index in the Autonomous Communities of Spain. Our case study of Spain, a developed country with clear gender and regional differences, demonstrates the importance of adjusting human development indices in accordance with gender discrimination and regional inequalities. We also show the significance of the income component in assessing the development level of women in countries like Spain, where lack of employment or low remuneration are the chief characteristics of women's inequality. Our analysis makes clear that the Gender-Related Human Development Index has limited applicability in developed countries; it also illustrates the need for alternative variables or models to assess inequality in those countries.  相似文献   
825.
This paper studies optimal direct and indirect taxation in an endogenous growth framework with a productive public good and costly tax collection. Optimal (growth-maximizing) tax rules are derived under exogenous collection costs. The optimal direct–indirect tax ratio is shown to be negatively related to the administrative costs of collecting these taxes, as documented in cross-country data. This result also holds under endogenous collection costs (with these costs inversely related to administrative spending on tax enforcement), but for these to generate significant effects on tax collection requires implausibly high degrees of efficiency in spending, or the allocation of a large fraction of resources to tax enforcement. Depending on how it is financed, the latter policy may entail adverse effects on growth. Improving ‘tax culture’ and the sense of civic duty through greater budgetary transparency may be a more effective policy to improve tax collection and promote economic growth.  相似文献   
826.
The name of William Foote Whyte is most frequently associated with Street Corner Society, the sociological study of life in Boston's North End during the late 1930s, but his research spanned another sixty years in a range of settings on three continents. This article traces his achievements over the decades, as he developed and applied a participatory action research methodology in the kitchens of Chicago restaurants, the oilfields of Oklahoma and Venezuela, subsistence farms in Peru and Guatemala, and industrial cooperatives in the Basque region of Spain. It describes how this methodology, grounded in case research, led to social change at the “Tremont Hotel” in a Midwestern city. It questions why his achievements have not received greater recognition among by academicians and practitioners, perhaps because his ideas and findings on social change produced discomfort among peers and the sponsors of his research.  相似文献   
827.
We use data collected from a consumer survey of face‐to‐face interviews to determine consumer demand for genetically modified (GM) tofu attributes in Taiwan. Conjoint analysis using logit models reveals that, on average, brand is the most important attribute in terms of influence on consumers’ preferences, followed by price, with GM content having the least influence. However, the analysis also reveals three distinct market segments for tofu. Apart from the largest segment (which reflects the average lack of concern about GM food), the remaining two segments are split according to their preference or antipathy towards GM tofu. This result suggests that GM labelling is helpful to Taiwanese tofu consumers.  相似文献   
828.
The long-term structure of production, factor demand and factor productivity in the Canadian pulp and paper industry was studied for the period 1956 to 1982. A four input (labor, capital, material and energy) nonhomothetic translog cost function was used for the purpose. Least-cost combinations of the four factors were obtained by imbedding an interrelated dynamic adjustment process. These least-cost paths, from which the cyclical fluctuations due to business turns were filtered out, were then used to derive the long-term productivity of each input. Long-term elasticities of substitution and demand were also computed. Long-term and short-term results were compared. Important findings of the study were: (i) the long-term structure of production of the industry can be represented by the nomothetic version of the translog cost function, (ii) the long-term technological progress in the industry is slow despite evidence of some economies of scale in production, (iii) all factors of production in the industry are long-run substitutes despite short-run complementarities between some factors of production, (iv) each input was observed to be misallocated during the period of study as compared to the least-cost allocations, (v) observed productivity growth of capital, labor and energy declined during the seventies and early eighties, as compared to growth in the sixties, but growth in their long-run productivities did not, (vi) though both observed and long-run productivities of raw material declined the rate of decline was lower on the long-run path, and (vii) price increases in the pulp and paper industry after 1971 could have been lower than what was actually experienced if the industry could change with economic circumstances more rapidly. La structure à long terme de production, de facteur de demande et de facteur de productivité dans l'industrie canadienne de putpe et de papier est étudiée pour la période de 1956 à 1982. Une fonction de coût “nonhomothetic translog” avec quatre entrées (la main-d'oeuvre, le capital, le matériel et l‘énergie) est utilisée pour cette étude. Les combinaisons les moins chères des quatre facteurs sont obtenues en incluant un ajustement dynamique du processus d'interaction. Ces chemins les moins chers, desquels les fluctuations conjoncturelles dues aux changements d'affaires sont enlevées, sont utilisés pour dériver la productivité à long terme de chaque entrée. Les élasticités à long terme de substitution et de demande sont aussi calculées. Les résultats à long terme et ceux à court terme sont comparés. Les découvertes importantes de cette étude sont: (i) la structure à long terme de production de l’-industrie peut être représentée par la version “homothetic” de la fonction de coût “translog,” (ii) le progrès technologique à long terme dans l'industrie est lent malgré l‘évidence de certaines économies par la production à grande échelle, (iii) tous les facteurs de production dans l'industrie sont des substituts à long terme malgré les complémentarités à court terme parmi les facteurs de production, (iv) chaque entrée était allouée au mauvais endroit pendant la période d’étude à comparaison des allocations les moins chères, (v) la croissance de productivité observée de capital, de main-d'oeuvre et d‘énergie a diminué pendant les années soixante-dix et au début des années quatre-vingts, à comparaison de la croissance dans les années soixante, mais la croissance de leurs productivités à long terme n'a pas diminué, (vi) bien que les productivités observées et à long terme de matières premières ont diminué, les taux de diminution sont plus bas sur le chemin à long terme, et (vii) les augmentations de prix dans l'industrie de pulpe et de papier après 1971 auraient pu être plus bas qu'on n'a expérimenté si l'industrie était capable de changer plus rapidement selon les circonstances économiques.  相似文献   
829.
Most studies of input subsidy programmes confine their analyses to measuring programme effects over a one‐year period. This article estimates the potential longer‐run or enduring effects of fertiliser subsidy programmes on smallholder farm households' demand for commercial fertiliser and maize production over time. We use four waves of panel data on 462 farm households in Malawi for whom fertiliser use can be tracked for eight consecutive seasons between 2003/2004 and 2010/2011. Panel estimation methods are used to control for potential endogeneity of subsidised fertiliser acquisition. Results indicate that farmers acquiring subsidised fertiliser in three consecutive prior years are found to purchase slightly more commercial fertiliser in the next year. This suggests a small amount of crowding in of commercial fertiliser from the receipt of subsidised fertiliser in prior years. In addition, acquiring subsidised fertiliser in a given year has a modest positive impact on increasing maize output in that same year. However, acquiring subsidised fertiliser in multiple prior years generates no statistically significant effect on maize output in the current year. These findings indicate that potential enduring effects of the Malawi fertiliser subsidy programme on maize production are limited. Additional interventions that increase soil fertility can make using inorganic fertiliser more profitable and sustainable for smallholders in sub‐Saharan Africa and thereby increase the cost‐effectiveness of input subsidy programmes.  相似文献   
830.
This paper introduces a flexible multiproduct cost function that permits zero values of one or more of the outputs and can impose restrictions quite easily, if not automatically satisfied, to ensure global concavity property. It satisfies linear homogeneity (in prices) property and is flexible in the output space. Thus the function is ideal for estimating, for example, economies of scope, cost complementarity, product-specific returns to scale, etc., without worrying about zero values of output(s) and extrapolations to points far from the point of approximation. As an empirical application, we use panel data (1978–1985) on 12 Finnish foundry plants to estimate technical progress, overall returns to scale, product-specific returns to scale and economies of scope.  相似文献   
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