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1.
In this article, we account for the first time for long memory, regime switching and the conditional time-varying volatility of volatility (heteroscedasticity) to model and forecast market volatility using the heterogeneous autoregressive model of realized volatility (HAR-RV) and its extensions. We present several interesting and notable findings. First, existing models exhibit significant nonlinearity and clustering, which provide empirical evidence on the benefit of introducing regime switching and heteroscedasticity. Second, out-of-sample results indicate that combining regime switching and heteroscedasticity can substantially improve predictive power from a statistical viewpoint. More specifically, our proposed models generally exhibit higher forecasting accuracy. Third, these results are widely consistent across a variety of robustness tests such as different forecasting windows, forecasting models, realized measures, and stock markets. Consequently, this study sheds new light on forecasting future volatility. 相似文献
2.
This paper addresses a simple question: why do people vote? Though simple, this question remains unanswered despite the considerable attention it has received. In this paper, I show that purely rational–instrumental factors explain a large fraction of turnout variations, provided that the effect of the margin of victory on implemented policy is considered. I extend Myerson's models of elections based on Poisson games, and show that, when platforms are responsive to vote shares, the predictions of the model become consistent with several stylized facts, including the secular fall in turnout rates in the US. 相似文献
3.
Hardle Wolfgang; Herwartz Helmut; Spokoiny Vladimir 《The Journal of Financial Econometrics》2003,1(1):55-95
Price variations at speculative markets exhibit positive autocorrelationand cross correlation. Due to large parameter spaces necessaryfor joint modeling of variances and covariances, multivariateparametric volatility models become easily intractable in practice.We propose an adaptive procedure that identifies periods ofsecond-order homogeneity for each moment in time. To overcomethe high dimensionality of the problem we transform the multivariateseries into a set of univariate processes. We discuss thoroughlythe implementation of the adaptive technique. Theoretical andMonte Carlo results are given. We provide two applications ofthe new method. For a bivariate exchange rate series we comparethe multivariate GARCH approach with our method and find thelatter to be more in line with the underlying assumption ofindependently distributed innovations. Analyzing a 23-dimensionalvector of asset returns we underscore the case for adaptivemodeling in high-dimensional systems. 相似文献
4.
Calvyn Potgieter 《International Journal of Technology and Design Education》2004,14(3):205-218
In this article the impact of technology education, as a new learning area (subject) in the curriculum, on in-service teacher
education in South Africa is described in order to ascertain the extent of the impact. The research on which this article
is based draws on a variety of experiences and observations in the field at grassroots level (in particular an outreach project
in rural communities). The envisaged impact of technology education on South African schools, communities, teacher educators
and teachers, the range of in-service teacher education that is required, and the impacts in urban and rural areas are discussed.
Finally a number of concluding remarks are made about the extent of the impact of the inclusion of technology education in
the new National Curriculum Statement and whether the situation has changed since the implementation of a pilot technology
education project in 1998.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
This paper compares the approximation capabilities of the minflex-Laurents translog and minflex generalized Leontief cost functions with their translog and generalized Leontief counterparts in Monte Carlo experiments. The minflex Laurent specifications generally provided closer approximations to underlying technical and economic parameters. Imposition of nonlinear restrictions on some of the parameters of the minflex Laurent models yielded measurable improvement in estimated elasticities of substitutions, returns to scale, and rates of technical change.The refereeing process of this paper was handled through E. Appelbaum. 相似文献
6.
We give an example of a subspace K of such that , where denotes the closure with respect to convergence in probablity. On the other hand, the cone C ≔ K − L ∞ + is dense in L ∞ with respect to the weak-star topology σ( L ∞ , L 1 ) . This example answers a question raised by I. Evstigneev. The topic is motivated by the relation of the notion of no arbitrage and the existence of martingale measures in Mathematical Finance. 相似文献
7.
Lead markets, innovation differentials and growth 总被引:1,自引:0,他引:1
Marian Beise 《International Economics and Economic Policy》2005,1(4):305-328
This article suggests that the specialization of countries in international trade is determined by the lead-lag market pattern of national markets. Many internationally successful innovations have been adopted first in one country while other countries initially either preferred other designs or an established product. A model for the international diffusion of innovations is presented in which nationally preferred innovation designs compete to become a globally dominant design. In this model, there are country-specific market attributes that increase the likelihood that the choice a country makes among alternative technologies is followed around the world. It is argued that technological knowledge gaps are not the origin of an international competitive advantage. Instead, a country gains a competitive advantage because a specific innovation design was adopted earlier than in any other country. This gives local firms a head start in producing, gathering marketing intelligence and securing the property rights of a globally successful innovation. In countries with lag market characteristics, domestic innovations are less likely to get adopted worldwide. Lag markets often switch from a domestic innovation design to a foreign innovation design, which increases imports. The lead-lag market explanation of trade specialization has implications for national policies. In this model domestic innovations do not always foster exports; idiosyncratic innovations induced by lag market contexts can hamper the export chances of local firms and in the end lead to an increase in imports. It is suggested that in order to increase exports, national policies have to distinguish between a domestic lead and lag market context in each industry. While in a lead market context, traditional policy instruments that enhance the rate of innovations are effective, in a lag market situation national follower strategies are more appropriate. 相似文献
8.
9.
通过对公共服务的属性分析,结合新政治经济学理论和政府失败的现实因素,探索公益物品的有效供给模式,提出了公共服务的签约转包机制,并分析了这一机制的不足和政府的作用。 相似文献
10.
赵复强 《广西经济管理干部学院学报》2005,17(1):34-36
区域不平衡发展是一个普遍的规律,欠发达地区应根据不平衡发展理论,吸取经验教训,建立科学的不平衡发展促动机制。 相似文献