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951.
In this article, the authors discuss the use of Federal Reserve Economic Data (FRED) statistics to teach the concept of price elasticity of demand in an introduction to economics course. By using real data in its computation, they argue that instructors can create a value-adding context for illustrating and applying a foundational concept in economics. Additionally, this pedagogical strategy contributes to developing an expected proficiency for economics majors related to “interpreting and manipulating data” (Hansen 2009, 2012). The authors provide step-by-step instructions on how to use FRED to compute the price elasticity of demand for motor vehicle fuels and gasoline as well as examples of in-class discussion questions and take-home assignments related to this instructional technique.  相似文献   
952.
Today’s companies still rely heavily on expert knowledge rather than quantitative data with a systematic approach to effectively identify and choose Research and Development (R&D) partners. It is advantageous to identify and select potential R&D partners using a Problem & Solution (P&S) pattern. This paper presents a novel process for identifying R&D partners on the basis of solution similarities that assist technology managers in understanding the relationships between research targets. First, we choose a thematic dataset that contains problems and quantitative data with relative topic terms. Then, we extract Subject-Action-Object semantic structures in a P&S pattern from the dataset, and identify various solutions to a technical problem, with each as a subject. In addition, we provide correlation mapping to visualise the text characters and identify R&D partners. Finally, we validate the proposed method through a case study of the dye-sensitized solar cells sector.  相似文献   
953.
The question of public debt management for both developed and developing economies has generated an enormous amount of political as well as academic interest. This study examines how governance affects public debt accumulation in the MENA countries during the 1996–2015 period. The six Worldwide Governance indicators (voice and accountability, political stability and the absence of violence/terrorism, government effectiveness, regulatory quality, rule of law and control of corruption) were used to measure the quality of governance in these countries. The results show that only three governance indicators support well the hypothesis that poor governance leads to higher accumulation of MENA public debt. Moreover, the estimates suggest a significant indirect impact of bad governance operating via decreased GDP growth. These findings have important implications for policy makers of these countries, which are currently facing major fiscal and external imbalances due to the high cost of war and terrorist attacks, low oil prices and a decline in trade. Sound public debt management represents an urgent task especially that public debt management problems often find their origins in the lack of attention paid by policymakers to the costs of bad governance and weak macroeconomic management.  相似文献   
954.
Background: A phase III trial evaluated the efficacy and safety of Daklinza (daclatasvir or DCV) in combination with sofosbuvir (SOF) for treatment of genotype (GT) 3 hepatitis C virus (HCV) patients.

Aim: This study evaluated the cost-effectiveness of DCV?+?SOF vs SOF in combination with ribavirin (RBV) over a 20-year time horizon from the perspective of a United States (US) payer.

Methods: A published Markov model was adapted to reflect US demographic characteristics, treatment patterns, costs of drug acquisition, monitoring, disease and adverse event management, and mortality risks. Clinical inputs came from the ALLY-3 and VALENCE trials. The primary outcome was the incremental cost-utility ratio. Life-years, incidence of complications, number of patients achieving sustained virological response (SVR), and the total cost per SVR were secondary outcomes. Costs (2014 USD) and quality-adjusted life years (QALYs) were discounted at 3% per year. Deterministic, probabilistic, and scenario sensitivity analyses were conducted.

Results: DCV?+?SOF was associated with lower costs and better effectiveness than SOF?+?RBV in the base case and in almost all scenarios (i.e. treatment-experienced, non-cirrhotic, time horizons of 5, 10, and 80 years). DCV?+?SOF was less costly, but also slightly less effective than SOF?+?RBV in the cirrhotic and treatment-naïve population scenarios. Results were sensitive to variations in the probability of achieving SVR for both treatment arms. DCV?+?SOF costs less than $50,000 per QALY gained in 79% of all probabilistic iterations compared with SOF?+?RBV.

Conclusion: DCV?+?SOF is a dominant option compared with SOF?+?RBV in the US for the overall GT 3 HCV patient population.  相似文献   
955.
Aim: To assess the cost-effectiveness of nutrition education by dedicated dietitians (DD) for hyperphosphatemia management among hemodialysis patients.

Materials and methods: This was a trial-based economic evaluation in 12 Lebanese hospital-based units. In total, 545 prevalent patients were cluster randomized to DD, trained hospital dietitian (THD), and existing practice (EP) groups. During Phase I (6 months), DD (n?=?116) received intensive education by DD trained on renal nutrition, THD (n?=?299) received care from trained hospital dietitians, and EP (n?=?130) received usual care from untrained hospital dietitians. Patients were followed-up during Phase II (6 months).

Results: At baseline, EP had the lowest weekly hemodialysis time, and DD had the highest serum phosphorus and malnutrition-inflammation score. The additional costs of the intervention were low compared with the societal costs (DD: $76.7, $21,007.7; EP: $4.6, $18,675.4; THD: $17.4, $20,078.6, respectively). Between Phases I and II, DD showed the greatest decline in services use and societal costs (DD: –$2,364.0; EP: –$1,727.7; THD: –$1,105.7). At endline, DD experienced the highest decrease in adjusted serum phosphorus (DD: –0.32; EP: +0.16; THD: +0.04?mg/dL), no difference in quality-adjusted life-years (QALY), and the highest societal costs. DD had a cost-effectiveness ratio of $7,853.6 per 1?mg decrease in phosphorus, compared with EP; and was dominated by THD. Regarding QALY, DD was dominated by EP and THD. The results were sensitive to changes in key parameters.

Limitations: The analysis depended on numerous assumptions. Interpreting the results is limited by the significant baseline differences in key parameters, suggestive of higher baseline societal costs in DD.

Conclusions: DD yielded the greatest effectiveness and decrease in societal costs, but did not affect QALY. Regarding serum phosphorus, DD was likely to be cost-effective compared with EP, but had a low cost-effectiveness probability compared with THD. Regarding QALY, DD was not likely to be cost-effective. Assessing the long-term cost-effectiveness of DD, on similar groups, is recommended.  相似文献   
956.
ABSTRACT

This study investigates the effects of government spending shocks on various key macro variables in China, Korea, and Japan using structural VAR models. The main empirical findings are as follows. Government spending multipliers of all three countries are far larger than 1 in recent years. The effectiveness of fiscal expansion has not changed markedly in China but substantially increased in Korea (after the Asian financial crisis) and Japan (during zero lower bound period). Increases in the effectiveness of fiscal expansion are associated with changes in the monetary and exchange rate policy regimes and institutions of these countries. Among the three countries, the government spending multiplier is relatively large in China but relatively small in Japan in recent years. Although the effects on exchange rate and trade balance vary across countries and sample periods, real exchange rate tends to depreciate, whereas trade balance tends to improve under flexible exchange rate regimes. Some empirical findings are consistent with standard theory, but others are not.

Abbreviations: NK: New Keynesian VAR: Vector Autoregressive ZLB: Zero Lower Bound  相似文献   
957.
采用随机前沿模型对2015—2020年中国内地107家军民融合企业技术创新效率进行测算,并基于军民融合企业专利数据构建技术多元化、发明者网络嵌入(结构洞和网络密度)等指标。运用社会网络分析与多元线性回归方法,实证分析技术多元化、发明者网络嵌入及两者交互作用、结构洞与网络密度的互补关系/平衡关系对军民融合企业技术创新效率的影响。结果发现:技术多元化、结构洞及两者交互作用对军民融合企业技术创新效率具有正向影响;网络密度及其与技术多元化的交互作用对军民融合企业技术创新效率具有负向影响;网络密度和结构洞的互补关系会抑制军民融合企业技术创新效率提升,但两者在军民融合企业内部的平衡关系能够促进军民融合企业技术创新效率提升。  相似文献   
958.
Forest resource extraction by local communities has been cited as a major impediment to the efficient management of protected forests. This paper develops a two sector dynamic model for farming and forest resource extraction by communities living in the forest periphery. The model assumes that land under forestry is constant and households allocate their time to farming and forestry. Comparative dynamic results suggest that higher prices for agriculture output, lower input prices, better knowledge of farming techniques and a lower discount rate may result in a higher equilibrium stock of forest resources. Tobit analysis with primary data collected from the Sinharaja forest in Sri Lanka provides supportive empirical evidence.  相似文献   
959.
The subjectivism of Austrian economics helps to explain the statistical fact of long memory in asset prices. The theory of Big Players is an Austrian approach to understanding the effects of discretionary policymaking in markets. It leads to implications that can be tested with statistics. In particular, Big Players induce herding and, thereby, an increase of persistence in asset prices. A recent episode in Slovenian monetary theory provides a case study. This case study adds to a set of similar studies, all tending to support the theory of Big Players.  相似文献   
960.
Tests of unit roots and other nonstationary hypotheses that were proposed by Robinson (1994) are applied in this article to the Nelson and Plosser's (1982) series. The tests can be expressed in a way allowing for structural breaks under both the null and the alternative hypotheses. When applying the tests to the same dataset as in Perron (1989), we observe that our results might be consistent with those in Perron (1989) when testing the nulls of trend-stationarity or a unit-root. However, we also observe that fractionally integrated hypotheses may be plausible alternatives in the context of structural breaks at a known period of time. Final version received: August 2000/Final version accepted: August 2001 RID="*" ID="*"  The author gratefully acknowledges the financial support from the European TMR grant No. ERBFMRX-CT-98-0213. Comments of two anonymous referees are also acknowledged.  相似文献   
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