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991.
This paper examines the impact that publicly funded agricultural research has on productivity in crop production within Thailand. It tests empirically the two hypotheses that, first, publicly funded research and development (R&D) in crop production is a significant determinant of total factor productivity (TFP) in the crop sector and, second, that its social rate of return is high. The statistical analysis applies error correction methods to national level time series data for Thailand, covering the period 1970–2006. Emphasis is given to public research in crop production, where most publicly funded agricultural R&D has occurred. The role of international research spillovers and other possible determinants of TFP are also taken into account. The results demonstrate that public investment in research has a positive and significant impact on TFP. International research spillovers have also contributed to TFP. The results support the finding of earlier studies that returns on public research investment have been high. This result holds even after controlling for possible sources of upward biases present in most such studies, due to the omission of alternative determinants of measured TFP. The findings raise a concern over declining public expenditure on crop research, in Thailand and many other developing countries.  相似文献   
992.
Academics and practitioners agree that the enforcement of accounting standards has an important role in promoting high quality financial reporting and favourable capital market outcomes. We test three new enforcement proxies from Brown, Preiato and Tarca (2014) that focus specifically on auditing and accounting enforcement. We examine firms’ information environments, represented by the error in analysts’ consensus forecasts and the extent of disagreement among analysts, as indicated by forecast dispersion. For financial years ending from 2003 to 2009, we construct a sample of 357,034 firm–month observations on the errors and dispersion of analysts’ earnings forecasts for 10,769 firms domiciled in those 39 countries. We find that higher scores for all three proxies are associated with lower error and less disagreement in forecasts. In addition, we find that the indices have significant explanatory power when previously used enforcement proxies (such as Kaufmann et al.'s 2010 rule of law measure) are included in the regression models, pointing to the importance of specific measures of accounting enforcement. We conclude that accounting enforcement may be more important in securing favourable economic outcomes than has been previously realised, because researchers commonly have used noisier, more general legal proxies for enforcement that understate its marginal effects.  相似文献   
993.
This paper proposes downside risk measure models in portfolio selection that captures uncertainties both in distribution and in parameters. The worst-case distribution with given information on the mean value and the covariance matrix is used, together with ellipsoidal and polytopic uncertainty sets, to build-up this type of downside risk model. As an application of the models, the tracking error portfolio selection problem is considered. By lifting the vector variables to positive semidefinite matrix variables, we obtain semidefinite programming formulations of the robust tracking portfolio models. Numerical results are presented in tracking SSE50 of the Shanghai Stock Exchange. Compared with the tracking error variance portfolio model and the equally weighted strategy, the proposed models are more stable, have better accumulated wealth and have much better Sharpe ratio in the investment period for the majority of observed instances.  相似文献   
994.
《Economic Systems》2020,44(1):100731
We have incorporated a financial accelerator mechanism operating through investments in the business sector in a dynamic macroeconometric model of the Norwegian economy. In this new and amended model aggregated credit and equity prices are determined simultaneously in a system characterized by a two-directional contemporaneous causal link, which has been designed and estimated by a new procedure for simultaneous structural model design. Combined with a mechanism where credit and asset prices are mutually influenced by real investments, this creates a financial accelerator amplified by a credit-asset price spiral. Simulations illustrate how the introduction of a financial accelerator significantly reinforces and extends the economic cycles in projections and forecasts, in particular when confronted by a severe shock. Furthermore, monetary policy has a markedly stronger effect in the short and medium term, while the impact of fiscal policy is affected to a relatively small degree as it is more remotely linked to financial markets.  相似文献   
995.
In this paper we analyze the estimation accuracy of high–low spread estimator. It is found that the performance of high–low spread estimator depends on the size of the true spread, the level of transaction frequency, and the degree of volatility. Analyzing the probability of measurement error, it is shown that the high–low spread estimators have better performance when the size of the spread is even wider, when the level of transaction frequency is even higher, or when the degree of volatility is relatively lower.  相似文献   
996.
Abstract

This paper provides a practical guide to Bayesian estimation of simultaneous entry games of complete information with heterogeneous firms. Bayesian inference requires computation of the likelihood, which is carried out by simulating unobservables. To avoid errors from finite simulations, we apply Andrieu and Roberts’s [2009. The pseudo-marginal approach for efficient Monte Carlo computations, Annals of Statistics, 37(2), pp. 697–725] pseudo-marginal approach. We rely also on adaptive Markov chain Monte Carlo algorithms that improve computational performance.  相似文献   
997.
高军妮 《价值工程》2011,30(1):32-32
在测量过程中,无论是直接测量还是间接测量,都无法做到完全消除测量误差。测量误差的来源是多方面的,本文通过对测量误差主要来源的分析,以有效的对其产生来源进行控制,以减少测量误差的产生。  相似文献   
998.
液压CAT系统测试误差分析   总被引:1,自引:0,他引:1  
胡森  胡晓波 《价值工程》2011,30(19):165-165
本文对液压CAT技术的发展现状和趋势进行了探讨,并对液压元件CAT系统误差来源进行了分析,介绍一些液压CAT系统误差处理办法。  相似文献   
999.
It is commonly accepted that information is helpful if it can be exploited to improve a decision making process. In economics, decisions are often based on forecasts of the upward or downward movements of the variable of interest. We point out that directional forecasts can provide a useful framework for assessing the economic forecast value when loss functions (or success measures) are properly formulated to account for the realized signs and realized magnitudes of directional movements. We discuss a general approach to (directional) forecast evaluation which is based on the loss function proposed by Granger, Pesaran and Skouras. It is simple to implement and provides an economically interpretable loss/success functional framework. We show that, in addition, this loss function is more robust to outlying forecasts than traditional loss functions. As such, the measure of the directional forecast value is a readily available complement to the commonly used squared error loss criterion.  相似文献   
1000.
苏梽芳  臧楠 《财经研究》2011,(2):112-123
食品通胀率与非食品通胀率之间的测量缺口近期持续扩大,引起了市场广泛关注。文章根据1994年1月至2010年8月的食品价格与非食品价格数据,运用两区制门槛误差修正模型研究两者的长期均衡关系和短期价格调整以及传导机制中的非线性特征。结果发现,食品通胀率与非食品通胀率存在门槛协整关系,而且估计缺口稳定,这表明测量缺口夸大了两者的真实偏离。文章还发现了食品价格传导的新信息内涵,即食品价格对非食品价格具有非线性的价格传导性:短期内偏离主要是食品价格上升造成,尤其是在高通货膨胀区制,偏离速度有加快趋势。两区制的Granger因果关系检验发现,在极端区制,食品价格通胀与非食品价格通胀具有双向的短期Granger原因,即两者相互领先;而在正常区制,食品价格通胀与非食品价格通胀具有双向的长期Granger原因。  相似文献   
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