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91.
In 1996 the federal government enacted the Federal Agriculture Improvement and Reform (FAIR) Act, which represented a sweeping change in public policy toward agriculture. This paper examines the impact of the FAIR legislation on farmland values across the U.S. Corn Belt. A representative farm framework is used to determine the impact of FAIR on farmland values. The analysis suggests that marginal production environments are likely to suffer most severely under FAIR, and that a prolonged period of weak commodity prices could engender sharp declines in farmland values.  相似文献   
92.
93.
Aims: To assess the frequency of biopsies and molecular diagnostic testing (human DNA/RNA analysis), anti-cancer drug use (genomically-matched targeted therapy [GMTT], unmatched targeted therapy [UTT], endocrine therapy [ET], and chemotherapy [CT]), and medical service costs among adults with metastatic cancer.

Methods: Adults diagnosed with metastatic breast, non-small cell lung (NSCLC), colorectal, head and neck, ovarian, and uterine cancer (2010Q1–2015Q1) were identified in the OptumHealth Care Solutions claims database and followed from first metastatic diagnosis for ≥1 month and until the end of data availability. Utilization was assessed for each cancer cohort (all and patients aged ≥65 years); per-patient-per-month (PPPM) medical service costs were assessed for all patients. Testing frequency estimates were applied to Surveillance, Epidemiology, and End Results Program data to estimate the number of untested patients (2010–2014).

Results: Patients with metastatic cancer (n?=?8,193; breast [n?=?3,414], NSCLC [n?=?2,231], colorectal [n?=?1,611], head and neck [n?=?511], ovarian [n?=?275], and uterine [n?=?151]) were 63 years old (mean), with 11.1–22.2 months of observation. Biopsy and molecular diagnostic testing frequencies ranged from 7% (uterine) to 73% (ovarian), and from 34% (head and neck) to 52% (breast), respectively. Few were treated with GMTT (breast, 11%; NSCLC, 9%; colorectal, 6%). Treatment with UTT ranged from 0.7% (uterine) to 21% (colorectal). Biopsy, diagnostic testing, and anti-cancer drug therapy were less frequent for those ≥65 years. Medical service costs (PPPM, mean) ranged from $6,618 (head and neck) to $9,940 (ovarian). The estimated number of untested new patients with metastatic cancer was 636,369 (all) and 341,397 (≥65).

Limitations: In addition to the limitations of claims analyses, diagnostic testing frequency may be under-estimated if patients underwent testing prior to study inclusion.

Conclusions: The low frequency of molecular diagnostic testing suggests there are opportunities to better inform management of patients with advanced cancer, particularly decisions to treat with GMTT.  相似文献   
94.
This paper examines how preferences for social reputation affect the design of monetary incentives in an efficient mechanism for environmental risk. Our results are a high reputation firm receives less than optimal transfer; the low reputation firm sacrifices information rent.  相似文献   
95.
This research examines whether suppliers’ capabilities impact OEM customers’ dependence on the supplier and thereby generate customer loyalty. Using a sample of purchasing managers focusing on a single key component supplier, we examine three supplier capabilities, two dependence dimensions, and three aspects of customer loyalty. Core offering capability increases the customer firm’s benefit-based dependence. Operations capability has a more comprehensive effect, enhancing both benefit-based and cost-based dependence. Benefit-based dependence leads to relational loyalty and, through its effect on relational loyalty, to insensitivity to competitive offerings and future purchase expansion. Cost-based dependence motivates insensitivity to competitive offerings, but does not affect relational loyalty or purchase expansion. The supplier’s communication capability is associated with relational loyalty, but this effect does not flow through the customer firm’s dependence. The divergent pattern of antecedents and effects of benefit-based dependence and cost-based dependence may explain the inconsistent and insignificant research findings in previous research on dependence. Our results suggest that adopting a bi-dimensional model of dependence more fully captures the theoretical domain of dependence, thereby permitting researchers to better examine its role in supply chain, channel, and marketing relationships.  相似文献   
96.
In the current paper, we present an integrated genetic programming (GP) environment called java GP modelling. The java GP modelling environment is an implementation of the steady-state GP algorithm. This algorithm evolves tree-based structures that represent models of inputs and outputs. The motivation of this paper is to compare the GP algorithm with neural network (NN) architectures when applied to the task of forecasting and trading the ASE 20 Greek Index (using autoregressive terms as inputs). This is done by benchmarking the forecasting performance of the GP algorithm and six different autoregressive moving average model (ARMA) NN combination designs representing a Hybrid, Mixed Higher Order Neural Network (HONN), a Hybrid, Mixed Recurrent Neural Network (RNN), a Hybrid, Mixed classic Multilayer Perceptron with some traditional techniques, either statistical such as a an ARMA or technical such as a moving average convergence/divergence model, and a naïve trading strategy. More specifically, the trading performance of all models is investigated in a forecast and trading simulation on ASE 20 time-series closing prices over the period 2001–2008, using the last one and a half years for out-of-sample testing. We use the ASE 20 daily series as many financial institutions are ready to trade at this level, and it is therefore possible to leave orders with a bank for business to be transacted on that basis. As it turns out, the GP model does remarkably well and outperforms all other models in a simple trading simulation exercise. This is also the case when more sophisticated trading strategies using confirmation filters and leverage are applied, as the GP model still produces better results and outperforms all other NN and traditional statistical models in terms of annualized return.  相似文献   
97.
The new data source for the Australian Energy Statistics, the National Greenhouse and Energy Reporting System, does not require businesses using less than 200 terajoules to report their energy consumption. This results in a data gap in the total industry energy consumption. To estimate the gap, this study models business energy consumption using data from the Australian Bureau of Statistics' 2008–09 Energy, Water and Environment Survey and data from the 2008 to 2009 business activity statement unit record estimates. The article discusses the modelling approaches and methodological issues associated with the estimation of the National Greenhouse and Energy Reporting System's energy consumption under‐coverage. It provides estimation results and suggestions for future research, based on available data.
  相似文献   
98.
The creation of historic districts has become a common way to preserve historic buildings and neighborhoods. Advocates of historic districts assume that such districts augment, or at least, protect property values for homes within these districts. The existing economic literature supports this conclusion, but most studies seem to fall victim to an endogeneity bias since higher value homes are, all else equal, more likely to be included in districts. This study uses repeat-sales fixed effects (difference-in-differences) analysis to look at homes before and after the creation of districts in the Boston-Cambridge-Quincy MSA between 2000 and 2007, and thus control for this endogeneity bias. Secondarily, we re-examine the effects of a Massachusetts preservation policy, the Community Preservation Act (CPA) which, in part, supports historic preservation. We find evidence that the creation of a local historic district, on average, reduces home prices for homes in that district between 11.6 and 15.5%. This indicates that any restrictions implied by the creation of a district outweigh any benefits to homeowners within the district. If, instead, census block fixed effects are employed, the analysis shows a statistically insignificant impact, the sign and magnitude of which depends on the specification. Taken together with the repeat sales result, this confirms our intuition about the importance of controlling for omitted variables and endogeneity biases. Finally, we find evidence that the CPA also lowers property values, by less than 1%, and that being in a Historic District magnifies the negative effect of the CPA.  相似文献   
99.
We explore whether the recent laboratory findings that suggest the origin of endowment matters in simple bargaining games are actually due to contextual shifts of relative effort and deservingness. Results support previous findings of endowment origin yielding more self-interested behavior.  相似文献   
100.
We provide new results for two-stage games in which firms make capacity investments when demand is uncertain, then, when demand is realized, compete in prices. We consider games with demand rationing schemes ranging from efficient to proportional rationing. In all cases, there is a subgame perfect equilibrium outcome coinciding with the outcome of the Cournot game with demand uncertainty if and only if (i) the fluctuation in absolute market size is small relative to the cost of capacity, or (ii) uncertainty is such that with high probability the market demand is very large and with the remaining probability the market demand is extremely small. Otherwise, equilibria involve mixed strategies. Further, we show under efficient rationing that condition (i) is sufficient for the unique equilibrium outcome to be an equilibrium outcome of the Cournot game with demand uncertainty.  相似文献   
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