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101.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
102.
The frequency of use and the marginal costs and marginal value products of mastitis control practices on somatic cell count (SCC) and milk yield are investigated. A survey of current management practices is combined with Dairy Herd Improvement production information to determine the relationships between milk yield, SCC, management practices, and production and producer characteristics under field conditions. The relationships are modeled and compared at the cow and herd level. A moment-generating approach is used in the herd model to determine which, if any, practices are risk reducing. The SCC for an individual cow is a better indicator of milk production lost due to mastitis than is a bulk tank SCC. Most recommended mastitis control practices are estimated to be economically beneficial, but some common practices are found not to be economical, and questions are raised about dry cow treatment. On a examiné la fréquence à laquelle on recourt aux pratiques de lutte contre la mammite, de même que les couts et les avantages marginaux de ces dernières en ce qui concerne la numération des cellues somatiques et le rendement laitier. On a combiné une enquête sur les pratiques zootechniques actuelles aux renseignements sur la production extraits du Programme d'amélioration des troupeaux laitiers en vue de déterminer les relations qui existent entre le rendement laitier, la numération des cellules somatiques, la conduite du troupeau ainsi que les caractéristiques associées à la production et aux producteurs, sur le terrain. On a ensuite modélisé ces relations et on les a compareées entre les animaux et les troupeaux. Pour le modèle touchant les troupeaux, on s'est servi d'une approche générant des moments, pour déterminer si une pratique quelconque diminuait les risques. La numération des cellules somatiques chez la vache est un meilleur indicateur du volume de lait perdu à la suite de la mammite que la numération des cellules somatiques dans la citerne. La plupart des méthodes de lutte contre la mammite recommendées offrent un avantage économique, mais certaines pratiques courantes ont l'effet contraire et on s'interroge sur l'utilité de traiter les vaches taries.  相似文献   
103.
Off-farm labor supply in Canada is modeled using separate off-farm labor participation and off-farm labor supply equations, which allows variables to affect participation and labor supply differently. The data used in this study are from Statistics Canada's Agriculture-Population Linkage Database, which links the Population Census for 1986 to a 20% sample from the Census of Agriculture. Results indicate that age, education and wages have large, significant and opposite effects on participation and supply, and that government efforts to stabilize and supplement farm incomes through rural employment programs may have less effect on labor allocation decisions than do the underlying demographic factors and regional and farm characteristics.
Nous modélisons id les disponibilités d'emploi extérieur (hors-ferme) pour les agriculteurs, utilisant des équations distinctes pour la participation aux emplois extérieurs et pour l'offre des emplois extérieurs, ce qui permet de laisser les variables influer différemment sur les deux éléments. Les donées utilisées proviennent de la base de données de Statistique Canada sur le couplage agriculture-population, laquelle relie le recensement de la population de 1986 à un échantillon de 20 % prélevé sur le recensement de l'agriculture. Les résultats font voir que l'âge, le niveau de scolarisation et les salaires ont de grands effets, significatifs mais opposés, sur l'utilisation et sur les disponibilites d'emplois extérieurs et que les initiatives de'État pour stabiliser et compléter le revenu agricole au moyen de programmes d'emploi rural auraient mains d'effets sur les décisions d'attribution des emplois que les facteurs sous-jacents relevant de la démographie et des caractéristiques particulières de chaque région et exploitation.  相似文献   
104.
105.
An adverse selection model is utilized to demonstrate that informational asymmetry may make it wealth optimal for the financial intermediary (FI) to credit ration and to rationalize the existence of different lenders in the credit market. The crucial assumption is that borrowers differ in their tolerance for a lender-imposed default penalty, the severity of which also varies with the lender. The credit rationing portion proves that the FI will: 1) be forced by a binding regulatory constraint to overinvest in capital; 2) ration its worst risk class borrowers; 3) establish its optimal loan interest rate on the basis of the average quality of its loans and the interest rate elasticity of the borrower demand in its best risk category; and 4) decrease the total loan volume and increase the loan interest rate due to an increase in the capital requirement, but the effect on the default risk quality of its loan portfolio is ambiguous. The existence result is that if a lender has a high default penalty, he can charge a lower rate and attract only “good” borrowers, i.e., heterogeneous lender types encourage the screening of borrowers and vice versa.  相似文献   
106.
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108.
Using a large hand‐collected sample of all blockholders (ownership ≥ 5%) of S&P 1500 firms for the years 2002–2009, we first document significant individual blockholder effects on earnings management (accrual‐based earnings management, real earnings management, and restatements). This association is driven primarily by these large shareholders influencing rather than selecting firms’ financial reporting practices. Second, the market's reaction to earnings announcements suggests that investors recognize the heterogeneity in blockholders’ influence on earnings management. The results highlight the highly individualized effects of blockholders and a mechanism through which shareholders impact reported earnings.  相似文献   
109.
Portfolios are formed directly and exclusively upon residual return behavior in the months prior to portfolio formation. The empirical behavior of residual return in the post-formation period is then examined. Based upon the overall time period studied (1932 through 1977), the average residual return is essentially zero in the months subsequent to the portfolio formation. However, systematic (i.e., non-zero) residual behavior is observed in particular years. Moreover, the results suggest the possibility that ‘abnormal’ returns observed after certain events (e.g., earnings announcements) may at least in part reflect more general phenomena associated with being ‘winners’ and ‘losers’ in terms of residual returns in the months previous to the event.  相似文献   
110.
We examine whether managers’ trading decisions (both at a firm and personal level) are correlated with trading strategies suggested by the operating accruals and the post-earnings announcement drift (SUE) anomalies. We discuss advantages and disadvantages of the use of managerial trading activity to infer managers’ private valuation about their own securities. Our results provide corroborative evidence for the accruals anomaly, i.e., managers’ repurchase and insider trading behavior varies consistently with the information underlying the operating accruals trading strategy. On the other hand, we do not find corroborative evidence for the SUE anomaly.
Rodrigo S. VerdiEmail:
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