首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   300篇
  免费   16篇
财政金融   24篇
工业经济   37篇
计划管理   57篇
经济学   55篇
运输经济   11篇
旅游经济   17篇
贸易经济   73篇
农业经济   12篇
经济概况   30篇
  2023年   3篇
  2021年   1篇
  2020年   6篇
  2019年   12篇
  2018年   13篇
  2017年   13篇
  2016年   9篇
  2015年   7篇
  2014年   10篇
  2013年   48篇
  2012年   10篇
  2011年   13篇
  2010年   13篇
  2009年   16篇
  2008年   16篇
  2007年   8篇
  2006年   10篇
  2005年   7篇
  2004年   7篇
  2003年   10篇
  2002年   6篇
  2001年   7篇
  2000年   8篇
  1999年   2篇
  1998年   11篇
  1997年   6篇
  1996年   5篇
  1995年   3篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1990年   3篇
  1989年   3篇
  1988年   2篇
  1987年   2篇
  1986年   2篇
  1985年   6篇
  1984年   3篇
  1983年   2篇
  1982年   1篇
  1981年   3篇
  1979年   1篇
  1978年   3篇
  1973年   1篇
  1967年   1篇
排序方式: 共有316条查询结果,搜索用时 15 毫秒
1.
Abstract This paper provides evidence on the impact of company training, of post-compulsory education and of the UK Youth Training Scheme in the late 1980's on the earnings of 21-year-old employees in England and Wales. Earnings equations are estimated for each of seven groups of employees who have followed alternative routes from compulsory education into employment, allowing for selectivity into these routes. There are several findings, including: both high parental social class and better school qualifications help to channel people into higher status routes, while high local unemployment has the opposite effect; participation in company training in long spells substantially raises wages but short spells do not; YTS participation fails to raise, and possibly substantially lowers, wages even three years after graduation compared to those who left school at 16 and went to work and received no training; there is weak evidence that, even for those that do not enter higher education, it is better to stay on at school after 16 than go into YTS.  相似文献   
2.
Vendor Managed Inventory (VMI) involves the vendor making the replenishment decision for products supplied to a customer based on various inventory and supply chain policies. Information sharing between supply chain members is required in VMI. Sometimes VMI decisions are delayed and/or the information shared is inaccurate. This research examines the effects of information delay and accuracy, and the sharing of sales and forecast information in a VMI environment facing stationary and nonstationary demand. The simulation experiments show the impact of information delay, information inaccuracy, and information sharing on a variety of performance measures, including inventory levels and fill rates.  相似文献   
3.
This paper proposes two new weighting schemes that average forecasts based on different estimation windows in order to account for possible structural change. The first scheme weights the forecasts according to the values of reversed ordered CUSUM (ROC) test statistics, while the second weighting method simply assigns heavier weights to forecasts that use more recent information. Simulation results show that, when structural breaks are present, forecasts based on the first weighting scheme outperform those based on a procedure that simply uses ROC tests to choose and forecast from a single post-break estimation window. Combination forecasts based on our second weighting scheme outperform equally weighted combination forecasts. An empirical application based on a NAIRU Phillips curve model for the G7 countries illustrates these findings, and also shows that combination forecasts can outperform the random walk forecasting model.  相似文献   
4.
5.
Objective: To assess long-term healthcare costs related to ischemic stroke and systemic embolism (stroke/SE) and major bleeding (MB) events in patients with non-valvular atrial fibrillation (NVAF) treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Materials and methods: Optum’s Clinformatics Data Mart database from 1/2009–12/2016 was analyzed. Adult patients with ≥1 stroke/SE hospitalization (index date) were matched 1:1 to patients without stroke/SE (random index date), based on propensity scores. Patients with an MB event were matched to patients without MB. All patients had an NOAC dispensing overlapping index date, ≥12?months of eligibility pre-index date, and ≥1 NVAF diagnosis. The observation period spanned from the index date until the earliest date of death, switch to warfarin, end of insurance coverage, or end of data availability. Mean costs were evaluated: (1) per-patient-per-year (PPPY) and (2) at 1, 2, 3, and 4?years using Lin's method.

Results: The cost differences were, respectively, $48,807 and $28,298 PPPY for NOAC users with stroke/SE (n?=?1,340) and those with MB (n?=?3,774) events compared to controls. Cost differences of patients with vs without stroke/SE were $49,876, $51,627, $57,822, and $60,691 at 1, 2, 3, and 4?years post-index, respectively (p?p?Limitations: Limitations include unobserved confounders, coding and/or billing inaccuracies, limited sample sizes over longer follow-up, and the under-reporting of mortality for deaths occurring after 2011.

Conclusions: The incremental healthcare costs incurred by patients with vs without stroke/SE was nearly twice as high as those of patients with vs without MB. Moreover, each additional year up to 4?years after the first event was associated with an incremental cost for patients with a stroke/SE or MB event compared to those without an event.  相似文献   
6.
Objectives: Specific economic model types often become de facto standard for health technology appraisal over time. Markov and discrete event simulation (DES) models were compared to investigate the impact of innovative modeling on the cost-effectiveness of disease-modifying therapies (DMTs) in relapsing–remitting multiple sclerosis (RRMS). Fingolimod was compared to dimethyl fumarate (DMF; in highly active [HA] RRMS), alemtuzumab (in HA RRMS) and natalizumab (in rapidly evolving severe RRMS). Comparator DMTs were chosen to reflect different dosing regimens.

Materials and methods: Markov and DES models used have been published previously. Inputs were aligned in all relevant respects, with differences in the modeling of event-triggered attributes, such as relapse-related retreatment, which is inherently difficult with a memoryless Markov approach. Outcomes were compared, with and without different attributes.

Results: All results used list prices. For fingolimod and DMF, incremental cost-effectiveness ratios (ICERs) were comparable (Markov: £4206/quality-adjusted life year [QALY] gained versus DES: £3910/QALY gained). Deviations were observed when long-term adverse events (AEs) were incorporated in the DES (Markov: £25,412 saved/QALY lost, versus DES: £34,209 saved/QALY lost, fingolimod versus natalizumab; higher ICERs indicate greater cost-effectiveness). For fingolimod versus alemtuzumab, when relapse-triggered retreatment was included in the DES, large cost differences were observed (difference between incremental cost is £35,410 and QALY is 0.10).

Limitations: UK payer perspective, therefore societal approach was not considered. Resource utilization and utilities for both models were not derived from the subpopulations; as the focus is on model type, input limitations that apply to both models are less relevant.

Conclusions: Whilst no model can fully represent a disease, a DES allows an opportunity to include features excluded in a Markov structure. A DES may be more suitable for modeling in RRMS for health technology assessment purposes given the complexity of some DMTs. This analysis highlights the capabilities of different model structures to model event-triggered attributes.  相似文献   
7.
ABSTRACT

International retirement migration (IRM) is a growing phenomenon linked to increased longevity, early retirement, and improved financial status. Encompassing both travel and leisure experiences, IRM is a topic relevant to both tourism and leisure studies. By analysing the fictional movie series The Best Exotic Marigold Hotel (2012) and The Second Best Marigold Hotel (2015) from psychological, gerontological, and sociological theoretical perspectives, this paper examines motivation, goal setting, continuity and change, and identity development in IRM experiences within tourism and leisure contexts. This paper (a) identified motivations for IRM as finance, romantic relationships, social relations, self-esteem, self-fulfilment, and social norms; (b) in turn, time perception and attitude influence IRM emigrants’ priority and emotional fulfilment; (c) innovation extricates IRM emigrants from role loss and facilitates role change; and (d) IRM emigrants experience various identity development processes. A conceptual framework for IRM is proposed that purports to explain the IRM experience process and indicates that such an understanding of IRM should incorporate psychological, gerontological, and sociological perspectives.  相似文献   
8.
The Bottom of the Pyramid (BoP) is a popular paradigm within management circles concerning those in poverty. In this paper, we develop a critical analysis of BoP discourse and practice, drawing particularly on the works of Laclau and Mouffe, and enriched by post-development thinking as expressed in the works of Esteva and Escobar, among others. We argue that the BoP paradigm functions to reinforce market capitalist hegemony and – vitally – to conceal economic alternatives. Using the concepts of ‘discourse’, ‘hegemony’ and ‘performativity’, we analyse the politics of language and representation in the BoP discourse. Finally, we point to modes of scholarship that contribute to the nurturing and performance of diverse, non-capitalist economic worlds.  相似文献   
9.
This article assesses the impact of armed conflict on the drinking water service of Basrah from 1978 to 2013 through an ‘urban warfare ecology’ lens in order to draw out the implications for relief programming and relevance to urban studies. It interprets an extensive range of unpublished literature through a frame that incorporates the accumulation of direct and indirect impacts upon the hardware, consumables and people upon which urban services rely. The analysis attributes a step‐wise decline in service quality to the lack of water treatment chemicals, lack of spare parts, and, primarily, an extended ‘brain‐drain’ of qualified water service staff. The service is found to have been vulnerable to dependence upon foreign parts and people, ‘vicious cycles’ of impact, and the politics of aid and of reconstruction. It follows that practitioners and donors eschew ideas of relief–rehabilitation–development (RRD) for an appreciation of the needs particular to complex urban warfare biospheres, where armed conflict and sanctions permeate all aspects of service provision through altered biological and social processes. The urban warfare ecology lens is found to be a useful complement to ‘infrastructural warfare’ research, suggesting the study of protracted armed conflict upon all aspects of urban life be both deepened technically and broadened to other cases.  相似文献   
10.
Knoblock and Korf have determined that abstraction can reduce search at a single agent from exponential to linear complexity (Knoblock 1991; Korf 1987). We extend their results by showing how concurrent problem solving among multiple agents using abstraction can further reduce search to logarithmic complexity. We empirically validate our formal analysis by showing that it correctly predicts performance for the Towers of Hanoi problem (which meets all of the assumptions of the analysis). Furthermore, a powerful form of abstraction for large multiagent systems is to group agents into teams, and teams of agents into larger teams, to form an organizational pyramid. We apply our analysis to such an organization of agents and demonstrate the results in a delivery task domain. Our predictions about abstraction's benefits can also be met in this more realistic domain, even though assumptions made in our analysis are violated. Our analytical results thus hold the promise for explaining in general terms many experimental observations made in specific distributed AI systems, and we demonstrate this ability with examples from prior research.This research has been sponsored, in part, by the National Science Foundation under grants IRI-9015423 and IRI-9010645, by the University of Michigan Rackham Graduate School, and by a Bell Northern Research Postgraduate Award.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号