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11.
“Nonpracticing entities” (NPEs) own patents but do not practice the patented technologies. They are sometimes referred to as “patent trolls,” who hold up practicing companies to seek exorbitant payments. This paper conducts a review of the theoretical literature, which is inconclusive on whether NPEs have been systematically overcompensated. This study offers the first empirical study in license royalty rates, and its econometric analysis demonstrates that NPEs have not been overcompensated in license markets, regardless of whether other relevant variables are controlled. This conclusion is then put back into the larger context of NPE economics to lay out topics for further research through cross-examining other major conclusions in this field.  相似文献   
12.
Invasive animal pests reduce crop and livestock output, require management and control measures, and threaten native plants, animals and their habitat. The agricultural and management costs are often directly measurable. But the costs to protect threatened native plants and animals are harder to assess. The Rural Lands Protection Boards were the government agency in New South Wales that managed invasive animals. An analysis of their decisions provided the opportunity to estimate the costs of protecting native species. The number of native plants and animals threatened by invasive pests was modelled against the expenditure, area, pest abundance, climate and location of 38 Board districts. There was a strong negative relationship between the number of threatened native species and Board expenditure. This relationship was interpreted to estimate the marginal cost of protecting a threatened native species, the downward shift in the supply curve necessary to protect all threatened native species, and the gains from the shift in the form of cost savings in the continued protection of non-threatened native species. These results value some of the costs that invasive animal pests impose on the environment.  相似文献   
13.
A recent paper by Hardaker et al. (The Australian Journal of Agricultural and Resource Economics, 48, 2004a, 253) and book by Hardaker et al. (Coping with Risk in Agriculture, 2004b) describe a procedure for determining an efficient set from among a set of random alternatives. This procedure, called stochastic efficiency with respect to a function (SERF), is claimed to make the same assumption concerning the risk aversion measures as does stochastic dominance with respect to a function (SDRF). This is claim is incorrect. SERF imposes an additional requirement on the risk aversion measures of the decision makers. Both procedures assume a lower and an upper bound on risk aversion, but SERF also assumes that all risk aversion measures are of the same functional form as these lower and upper bound functions. This additional strong requirement on risk preferences implies that the efficient set identified under SERF is usually smaller than that identified using SDRF.  相似文献   
14.
This paper reports on a system dynamics simulation model which was developed to study the diffusion of medical technologies but which should be applicable to other sorts of technologies as well. The model addresses both the adoption and the changing extent of use of an evolving, product-based technology and also endogenously accounts for changes in actual and perceived performance. Two specific medical case studies provide background to the model and are used for testing the model's ability to reproduce various aspects of historical behavior. The model's relatively complex structure is presented in the form of influence diagrams showing major flows and relationships. The paper concludes with a discussion of contributions and possible future uses and modifications of the model.  相似文献   
15.
This paper examines, via real data, some well known models for technology substitution analysis. We propose a family of data-based transformed models that will include the models under examination as special cases. The basic thrust of the paper is the recognition that for technology substitution analysis, the observations are time series data and hence are not independent. Also, the functional form of the model should be determined by both theoretical considerations as well as the data on hand. This suggests that the traditional ordinary least squares procedure used in estimating the parameters and the resulting forecasting procedures are not adequate. The existing models examined here are Fisher–Pry, Gompertz, Weibull, and Normal. We stress the statistical aspects of the models and their relative merits in terms of predictive power. The criteria used for the purpose of comparison are the mean squared deviation and the mean absolute deviation of the predicted values compared with the actual observations.  相似文献   
16.
Structural changes in Saskatchewan agriculture have led to significant changes in the time allocation of labor of farm women. This paper analyzes the nonfarm labor market participation and labor supply of farm women in the theoretical context of a household production function and contrasts them with those of men. Participation is analyzed using probit models, and nonfarm labor supply functions are estimated using tobit models. Personal characteristics such as age, education, number of children and nonfarm labor participation of the spouse are significantly related to the nonfarm labor market participation and labor supply of farm women, and the direction of influence is as expected. Farm characteristics such as farm size and type are significant in the case of males but not for females. Labor market characteristics are represented only by distance to the nearest center of Complete Shopping Center status or higher and, while this variable is negatively significant for males as expected, it is not significant for females Les changements structurels qui on frappé l'agriculture de la Saskatchewan ont entraîné des modifications significatives à la répartition du temps des agricultrices en matière de travail. L'article présente une analyse de la participation au marché du travail non agricole, ainsi que de l'offre de main-d'oeuvre des agricultrices, dans le contexte théorique d'une fonction de production de ménage, en comparaison avec la situation observée chez les hommes. Le degré de participation e'tait analysé à partir de modèles probit et les fonctions d'offre de main-d'oeuvre non agricole étaient estimées à partir de modéles tobit. Les caractères personnels comme l'âge, I'instruction, le nombre d'enfants et la participation du conjoint à un travail non agricole étaient significativement reliés, dans le sens attendu, à la participation des femmes au marché du travail non agricole et au temps qu'elles pouvaient y consacrer. Les caractères de l'exploitation, superficie et type, n'étaient significatifs que pour les hommes mais pas pour les femmes. Le seul caractére du marché de main-d'oeuvre considéré était la distance entre la ferme et l'agglomération la plus proche de niveau de centre commercial complet ou de niveau supérieur. Bien que, comme on pouvait s'y attendre, cette variable était significativement négative dans le cas des hommes, elle n'avait pas de valeur significative pour les femmes  相似文献   
17.
18.
Abstract

This note provides new evidence concerning American institutionalism at Chicago during the 1920s and 1930s.  相似文献   
19.
Support for the two-tier approach to income maintenance for the aged is becoming widespread. Two-tier formulas combine an income-conditioned bottom tier with an earnings-related top tier to achieve antipoverty and earnings replacement objectives. This paper first refutes the claim that the two-tier approach is generally more target-efficient in reaching the poor than is the earnings-related top tier with progressive replacement rates. Next, the paper compares the effectiveness of the two systems in terms of other goals. The paper concludes by showing that a top tier with a low tax on current income can virtually dominate a wide range of two-tier formulas.  相似文献   
20.
我经常说的一个例子,就是美国东部的羊群和西部的羊群是一个品种,但东部的羊的身体状况完全不一样,因为东部有狼,羊要不停地奔跑.但是西部没有狼,羊的日子过得挺好.……  相似文献   
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