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981.
Markets for illicit drugs present an interesting case study for economics, combining non-standard characteristics such as addiction and product illegality. One response has been to argue the generality of economic principles by suggesting that they apply even in the extreme case of markets for addictive substances, e.g., by showing that demand for illicit goods is responsive to price [1] [Reframing health behavior change with behavioral economics. Hillsdale, NJ:Lawrence Earlbaum Associates; 2000. p. 89-111.] and even by modeling addiction as rational [2] [J Political Econ 1988;96:675-700]. This paper sketches examples of an alternative reaction, focusing on idiosyncrasies of drug markets that might plausibly create counter-intuitive effects, including supply curves that slope downward because of enforcement swamping and/or a good serving as the only available store of wealth for its producer, demand reduction programs that increase demand, and consumption by “jugglers” possibly increasing rather than decreasing as prices rise. This analysis yields non-obvious policy recommendations; for example, source country control programs should concentrate on growing regions with a healthy banking sector.  相似文献   
982.
This paper describes a test of the null hypothesis that the first K autocorrelations of a covariance stationary time series are zero in the presence of statistical dependence. The test is based on the Box–Pierce Q statistic with bootstrap-based P-values. The bootstrap is implemented using a double blocks-of-blocks procedure with prewhitening. The finite sample performance of the bootstrap Q   test is investigated by simulation. In our experiments, the performance is satisfactory for samples of n=500n=500. At this sample size, the differences between the empirical and nominal rejection probabilities are essentially eliminated.  相似文献   
983.
This research examines the high level of change in supply organizations of large North American companies using data collected from 51 large North American supply organizations in 1987, 1995 and 2003. Analysis is supplemented by an additional 55 companies for which data were collected in 1995 and 2003. The availability of longitudinal data from individual companies over a 16-year period provided a unique opportunity to trace changes made to each company's supply organizational structure and their roles and responsibilities. Findings suggest that the respondents made major changes in supply organizational structure, supply chain responsibilities, use of purchasing teams, supply involvement in major corporate activities (MCA) and CPO reporting line, title and background.  相似文献   
984.
There are many situations in life testing experiment where an item fail instantaneously and hence the observed lifetime is reported as zero. The items that fail prematurely are called early failures. We propose a modified Weibull distribution as a suitable model to represent such situations by mixture of a singular distribution at zero and a two parameter Weibull distribution. We obtain the maximum likelihood estimates of the parameters and their asymptotic distributions. The methods are illustrated on drying of woods under different experiments and schedules reported by Vanmann (Research report, 1991:2).  相似文献   
985.
Regulators often do not regulate all firms competing in a given sector. Due to product substitutability, unregulated competitors have incentives to bribe regulated firms to have them overstate their costs and produce less, thereby softening competition. The best collusion-proof contract entails distortions both for inefficient and efficient regulated firms (distortion ‘at the top’). But a contract inducing active collusion may do better by allowing the regulator to ‘team up’ with the regulated firm to indirectly tax its competitor. The best such contract is characterized. It is such that the unregulated firm pays the regulated one to have it truthfully reveals its inefficiency. We finally compare those contracts.  相似文献   
986.
987.
In recent years, it has become common to represent entrepreneurs as either necessity- or opportunity-driven. Drawing upon face-to-face interviews in England with 70 entrepreneurs trading wholly or partially off-the-books, this paper evaluates critically this dichotomous representation. The finding is that squeezing the motives of off-the-books entrepreneurs into one side or the other of this dichotomy not only over-simplifies their rationales since both necessity and opportunity motives are often involved but also obfuscates how their motives change over time. The outcome is a call to replace this either/or depiction with a richer and more nuanced both/and understanding of off-the-books entrepreneurs that recognises their diverse and dynamic motives.
Colin C. WilliamsEmail:
  相似文献   
988.
Imitators and optimizers in Cournot oligopoly   总被引:1,自引:0,他引:1  
We analyze a symmetric n-firm Cournot oligopoly with a heterogeneous population of optimizers and imitators. Imitators mimic the output decision of the most successful firms of the previous round à la Vega-Redondo, F., [1997. The evolution of Walrasian behavior. Econometrica 65, 375–384]. Optimizers play a myopic best response to the opponents’ previous output. Firms make mistakes and deviate from their decision rules with a small probability. Applying stochastic stability analysis, we find that the long run distribution converges to a recurrent set of states in which imitators are better off than are optimizers.  相似文献   
989.
Studies of innovation networking have frequently been concerned with the occurrence of dyadic relationships and with their apparent impact on simple measures of firm-level innovation outputs. This paper takes a more detailed look by analyzing the connection between different types of innovation and forms of networking. Based on the market novelty of innovation outcomes and the extent to which innovation activities require new competences, four types of innovation are identified. It is proposed that these types correlate with various innovation network dimensions, including the volume of networks, the strength and content of ties, and the specificity of ties. Drawing on survey data of 594 innovations realized by Dutch small firms, it is observed that the requirement to access new competences for innovation correlates positively with the number of network partners involved. We also note more subtle connections between types of innovation and networking, including that novel innovation outputs correlate with using network partners as a source of inspiration, whilst new competences associate with networking for knowledge capital. In the latter case, these activities also draw on new and intended ties relatively often, i.e. network partners which are actively sought out for the specific contributions they may make to the innovation process. Finally, innovation which is simultaneously new-to-the market and requires new competences uses strong ties relatively often. Implications for innovation policy and practice are discussed.  相似文献   
990.
Approximately 50% of nursing facilities in Texas petitioned for bankruptcy during the 1998–2004 period. Using a logit regression model tested for robustness, we find nursing facilities that are profit-seekers, chain members, pay higher than average wage rates, accept more intensive-care residents and obtain a larger than average portion of their funding from public sources are highly vulnerable to negative changes in regulatory policy decisions on Medicare and Medicaid reimbursement. Larger facilities having higher than average occupancy rates and quality of care are less susceptible to adverse decisions. The model correctly classifies a facility as either bankrupt or solvent in about 75% of cases. We also examine the duration of bankruptcy using accelerated failure-time models. It appears that the duration of bankruptcy depends on location, out-of-state ownership, length of ownership, volume of resident days supplied, total cost and proportion of revenues from Medicaid.  相似文献   
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