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101.
We respond to the new article by Hayo, Neumeier, and Westphal (HNW), which is a critique of our 2006 article. The principal contribution of that article wa  相似文献   
102.
What are the long-term effects of universal preschool programs on child outcomes? We review 26 studies using natural experiments to estimate the effects of universal preschool programs for children aged 0–6 years on child outcomes measured from third grade to adulthood. Studies comparing universal preschool with a mix of parental, family, and private modes of care show mixed effects on test scores and on measures related to health, well-being, and behavior. All estimates for outcomes related to adequate primary and secondary school progression, years of schooling, highest degree completed, employment, and earnings indicate beneficial average effects of universal preschool programs. Three of the included studies calculate benefits-to-costs ratios and find ratios clearly above one. Universal preschool tends to be more beneficial for children with low socioeconomic status and there are not consistently different effects for boys or girls. Only three studies compare two alternative types of universal preschool programs in terms of long-term outcomes.  相似文献   
103.
Climate change poses significant new risks and challenges for businesses and their supply chains. Additionally, in many sectors, Scope 3 indirect greenhouse gas emissions resulting from the sourcing and distribution of goods and services are larger than firms' own carbon footprints. Here we study how firms engage their key stakeholders in their supply chains in obtaining, processing, and transferring relevant climate change‐related information designed to overcome information asymmetry and drive sustainable development. Grounded in organisational information‐processing theory (OIPT), we draw on data from the Carbon Disclosure Project's Climate Change Supply Chain initiative for a qualitative content analysis of a large sample of global firms. Consistent with OIPT, we find that although firms primarily engage their supply chain partners in a variety of ways to reduce information uncertainty around indirect emissions data, effectively interpreting and managing broader sustainability information equivocality becomes a growing priority. Our findings further suggest that firms engage suppliers, customers, and other supply chain partners through basic, transactional, and collaborative types of engagement. We contribute to literatures on interorganisational information processing and sustainable supply chain management by providing a more detailed understanding of how firms engage supply chain partners in the context of climate change.  相似文献   
104.
Abstract

Aims: To evaluate total costs and health consequences of a colorectal cancer (CRC) screening program with colonoscopy, fecal immunochemical tests (FIT), and expanded use of multitarget stool DNA (mt-sDNA) from the perspectives of Integrated Delivery Networks (IDNs) and payers in the United States.

Materials and methods: We developed a budget impact and cost-consequence model that simulates CRC screening for eligible 50- to 75-year-old adults. A status quo scenario and an increased mt-sDNA scenario were modeled. The status quo includes the current screening mix of colonoscopy (83%), FIT (11%), and mt-sDNA (6%) modalities. The increased mt-sDNA scenario increases mt-sDNA utilization to 28% over 10 years. Costs for both the IDN and the payer perspectives incorporated diagnostic and surveillance colonoscopies, adverse events (AEs), and CRC treatment. The IDN perspective included screening program costs, composed of direct nonmedical (e.g. patient navigation) and indirect (e.g. administration) costs. It was assumed that IDNs do not incur the costs for stool-based screening tests or bowel preparation for colonoscopies.

Results: In a population of one million covered lives, the 10-year incremental cost savings incurred by increasing mt-sDNA utilization was $16.2 M for the IDN and $3.3 M for the payer. The incremental savings per-person-per-month were $0.14 and $0.03 for the IDN and payer, respectively. For both perspectives, increased diagnostic colonoscopy costs were offset by reductions in screening colonoscopies, surveillance colonoscopies, and AEs. Extending screening eligibility to 45- to 75-year-olds slightly decreased the overall cost savings.

Limitations: The natural history of CRC was not simulated; however, many of the utilized parameters were extracted from highly vetted natural history models or published literature. Direct nonmedical and indirect costs for CRC screening programs are applied on a per-person-per modality basis, whereas in reality some of these costs may be fixed.

Conclusions: Increased mt-sDNA utilization leads to fewer colonoscopies, less AEs, and lower overall costs for both IDNs and payers, reducing overall screening program costs and increasing the number of cancers detected while maintaining screening adherence rates over 10 years.  相似文献   
105.
We present and discuss measures for analyzing productivity in deterministic frontier models. A new efficiency measure is introduced allowing for discrimination among efficient organizational units. In addition, a new performance measure for analyzing productivity of organizational units is presented. This measure fulfills various properties of efficiency measures but relaxes the indicator property. Both new approaches are based on the development of efficiency vectors which is a new vector measure for measuring efficiency. The vector components are efficiency measures related to subsets of a production possibility set. The new approaches are applied in the context of data envelopment analysis.
Jens MüllerEmail:
  相似文献   
106.
Anomalies in the Foundations of Ridge Regression   总被引:1,自引:0,他引:1  
Errors persist in ridge regression, its foundations, and its usage, as set forth in Hoerl & Kennard (1970) and elsewhere. Ridge estimators need not be minimizing, nor a prospective ridge parameter be admissible. Conventional estimators are not LaGrange's solutions constrained to fixed lengths, as claimed, since such solutions are singular. Of a massive literature on estimation, prediction, cross–validation, choice of ridge parameter, and related issues, little emanates from constrained optimization to include inequality constraints. The problem traces to a misapplication of LaGrange's Principle, unrecognized singularities, and misplaced links between constraints and ridge parameters. Alternative principles, based on condition numbers, are seen to validate both conventional ridge and surrogate ridge regression to be defined. Numerical studies illustrate that ridge regression as practiced often exhibits pathologies it is intended to redress.  相似文献   
107.
This article argues that Danish flexicurity is preconditioned by craft unionism that has historically been predominant in the Danish trade union movement. It is furthermore argued that flexicurity was on the verge to disappear when it became famous in the early 2000s, although yet not completely dead.  相似文献   
108.
In conjunction with the rapidly advancing industrialization of Turkey, the segment of industrial insurance has also steadily gained in importance. People seeking cover for industrial risks situated in Turkey, however, face several rather significant constrictions. Whilst some of those may be circumvented at least partially, the Turkish situation raises the question of the need for legislative reform (possibly inspired by German law) in this area. Such would foster the development of more innovative and adequate insurance products by the Turkish insurance market.  相似文献   
109.
In the classical portfolio optimization problem considered by Merton, the resulting constant proportion investment plan requires a diffusive trading strategy. This means that, within any arbitrarily small time interval, the investor must impractically both buy and sell stocks. We study the problems of a mean-square and a power utility investor for whom the trading strategy is constrained to be smooth, i.e. nondiffusive. This means that over sufficiently small time intervals, the investor is either a seller or a buyer of stocks. The mathematical framework is built around quadratic objectives such that trading activity is punished quadratically. Mean-square utility is quadratic, and power utility is covered by quadratic punishment of distance to Merton’s power utility portfolio. We present semi-explicit solutions and, in a series of numerical illustrations, show the impact of trading constraints on the portfolio decision over the investment horizon.  相似文献   
110.
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