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941.
In the southern Great Plains of North America, fire exclusion has contributed to many rangelands converting from native grassland to woody shrublands dominated by mesquite (Prosopis glandulosa Torr.) and cactus (Opuntia spp.), threatening ecosystem health and human livelihoods in the region. Prescribed fire is the least expensive method of treating mesquite and other undesirable plants, but its role is as a maintenance treatment to prolong the life of more expensive brush control treatments. Using a simulation model of a hypothetical 1000 ha ranch, we evaluate the biological and economic implications of management scenarios involving the regular application of summer fire to reduce mesquite and cactus over a 30-year time period. We compared the model output with experimental data to corroborate model output before evaluating various management scenarios over a range of stocking rates. Scenarios included (a) varying initial range condition, (b) different frequencies of summer burning, and (c) different initial amounts of mesquite brush. Model simulations corroborated field data sufficiently well to give confidence in the output of the model. In our simulations the option of not treating to reduce brush and cactus had a major negative impact on range condition, secondary productivity and profitability. In contrast, all simulated fire treatments improved range condition, productivity and profitability except when initial range condition was poor. Initial range condition and stocking rate were the major factors affecting both productivity and profitability. Compared to other factors over which managers have short-term control, frequency of burning and the initial amount of mesquite cover, had a relatively minor impact. Simulations indicated that the highest level of profit consistent with maintaining or improving range condition was attained when individual animal production was 92-95% that of the maximum production per animal, a situation invariably associated with relatively low stocking rates.  相似文献   
942.
Abandoned industrial sites have traditionally constituted an important source of environmental problems. However, such sites are considered in many cases a historic heritage, and in this way, have been protected with different legal dispositions. Mining activities can be considered a special type of industrial site in that they encompass not only architectural but also landscape elements related to geology or topography. The necessity of developing new economic opportunities in these places, whose economy has been traditionally based on the “mining monoculture”, has resulted in the creation of a cultural revival in some mining sites. Nevertheless, these new economic potentials must be compatible with the obligation to maintain a low environmental risk in sites where the heavy metal concentrations are very high. The Cartagena-La Unión Mining District in Southern Spain is an example of such a case. This paper reviews the environmental situation in that area and the initiatives for establishing a cultural tourism. The goal of this paper is to incite the public debate about the balance between environmental risks, cultural safeguarding and economic development.  相似文献   
943.
M. Gartell 《Applied economics》2013,45(11):1449-1469
This article analyses the time it takes for Swedish college graduates to start a full time job that lasts for 6 months or more. The focus is on the transition over time during the period 1991 to 1999. This period covers both upturns and downturns of the business cycle, providing a unique opportunity to consider the importance of the timing of graduation. The results show that the risk of unemployment and the unemployment duration have varied considerably with the business cycle, both within and between cohorts. For example, the field of education is of more importance for the outcomes during recessions. Further, the relative risk of unemployment has decreased over time for individuals with the highest degree of education whereas the unemployment duration has increased, indicating that the selection into unemployment for this group may have changed over time. This is interesting, not least in the light of the sharp expansion of the higher educational system during the study period.  相似文献   
944.
This article investigates how the price indices of major cities of the US respond to the shock from a city and from monetary policy. We find that the crisis of Bretton Woods system in 1968 and the oil crisis in 1974 should be incorporated as structural breaks in monetary policy variables and price indices. Using cointegration technique with structural break in our aggregated data, we find that the average half-life is 1.75 years, which is closer to what some of others found in disaggregated data, and that the interest rate is an effective tool for controlling cities’ price in short run.  相似文献   
945.
Recent developments in the literature on Employment Protection Legislation (EPL) have revealed that changing the stringency of employment protection can lead to extensive consequences outside the labour market, by affecting firms’ production decisions or workers’ commitment levels. This article provides the first empirical evaluation of the comprehensive effect of restrictions on firing employees in Japan, by exploiting the variations in court decisions. We find that judgements lenient to workers significantly reduce firms’ total-factor productivity growth rate. The effect on capital is mixed and inconclusive, although we obtain modest evidence that an increase in firing costs induces a negative scale effect on capital inputs.  相似文献   
946.
We investigate the driving forces behind the level and the growth rate in real per capita Gross Domestic Product (GDP) in Indonesia. The ultimate reasons and the proximate causes underlying Indonesia's economic growth since the mid-1960s are still unclear. In the literature there have been at least three ways of investigating the driving forces of economic growth in Indonesia, namely: growth accounting system, regression and causality. The difference and improvement in this article is that we employed a two-step bounds testing approach to cointegration, which has not been done before; it uses the endogenous growth model to consider 12 policy variables and two external factors that potentially affect per capita income, this number is more than that has been done before. The empirical results that we obtained using this two-step bounds testing approach help us draw policy implications that if or when implemented would be expected to increase the growth of real per capita income, as well as the welfare of the people of Indonesia. Economic growth in Indonesia is largely driven by government policy, so the ability to increase Indonesia's economic growth rate, in the long run, will largely depend on the implementation of appropriate government policies.  相似文献   
947.
Researchers analysing time-use data often estimate limited dependent variable models because time spent must be nonnegative and cannot be more than the total amount of time in a given observation period. While the traditional empirical technique applied to such cases is maximum likelihood estimation of a Tobit (censored regression) model, recent debate has questioned whether linear models estimated via Ordinary Least Squares (OLS) are preferable. On the one hand, Tobit models are deemed necessary to address the significant censoring (i.e. large numbers of zeroes) typically found in time-use data, in the face of which OLS estimators would be biased and inconsistent. Yet, optimization occurs over a longer period than that covered by the typical time diary (often a day), and thus some argue that reported zeroes represent a measurement problem rather than true nonparticipation in the activity, in which case OLS would be preferred. We provide direct empirical evidence on this question using the Australian Time Use Surveys, which record time-use information for two consecutive diary days, by estimating censored and linear versions of a parental child care model for both 24-hour and 48-hour windows of observation in order to determine the empirical consequences of estimation technique and diary length.  相似文献   
948.
The organic dairy category is one of the fastest growing categories of organic foods in the US. Organic milk consumers generally cite perceived health benefits and lower risk of food contamination, as well as perceived superior quality and environmental sustainability of organic farming methods, as the major motivations for preference of organic over conventional milk. While the attributes of organic milk that are valued by consumers are fairly well-known, more ambiguity exists regarding the demographic characteristics of the typical organic milk consumer. This research makes use of experimental data from 148 adult participants and use a Classification and Regression Tree (CART) analysis, a nonparametric modelling approach, to identify how Willingness-to-Pay (WTP) for organic milk varies with the demographic profile of experiment participants. The study finds that perceived taste of organic milk, concern for the risk of consuming conventional milk, being a primary shopper, and the quantity of milk consumed are the major factors that separate experiment participants into groups with high and low WTP for organic milk.  相似文献   
949.
This article compares the Unemployment Rate (UR) as a measure of inefficiency with several other potential measures across 18 Organization for Economic Co-operation and Development (OECD) countries. Results show that the UR is not a very good measure of relative inefficiency between countries, it overestimates the number of individuals who would get jobs if the market is clear, the Dead Weight Losses (DWLs) of UR are remarkably low even in high unemployment countries and the aggregate perceived monetary losses by the unemployed as a proportion of Gross Domestic Product (GDP) are also uniformly low, although inframarginal individuals in some countries may perceive their losses to be high.  相似文献   
950.
In this article, I analyse the macroeconomic effects of monetary policy on the Portuguese economy. I show that a positive interest rate shock leads to: (i) a contraction of real GDP and a substantial increase of the unemployment rate; (ii) a quick fall in the commodity price and a gradual decrease of the price level and (iii) a downward correction of the stock price index. It also produces a ‘short-lived liquidity effect’ and helps explain the negative comovement between bonds and stocks. In addition, I find evidence suggesting the existence of a money demand function characterized by small output and interest rate elasticities. By its turn, the central bank’s policy rule follows closely the dynamics of the money markets. Finally, both the real GDP and the price level in Portugal would have been higher during almost the entire sample period if there were no monetary policy surprises.  相似文献   
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