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71.
This study proposes a new approach to the estimation of daily realised volatility in financial markets from intraday data. Initially, an examination of intraday returns on S&P 500 Index Futures reveals that returns can be characterised by heteroscedasticity and time-varying autocorrelation. After reviewing a number of daily realised volatility estimators cited in the literature, it is concluded that these estimators are based upon a number of restrictive assumptions in regard to the data generating process for intraday returns. We use a weak set of assumptions about the data generating process for intraday returns, including transaction returns, given in den Haan and Levin [den Haan, W.J., Levin, A., 1996. Inferences from parametric and non-parametric covariance matrix estimation procedures, Working paper, NBER, 195.], which allows for heteroscedasticity and time-varying autocorrelation in intraday returns. These assumptions allow the VARHAC estimator to be employed in the estimation of daily realised volatility. An empirical analysis of the VARHAC daily volatility estimator employing intraday transaction returns concludes that this estimator performs well in comparison to other estimators cited in the literature.  相似文献   
72.
This paper seeks to explain the productivity growth performance of Malaysia's manufacturing sector using a panel data of 28 industries from 1981–1996. Here, the data envelopment analysis technique is used to calculate and decompose the Malmquist index of total factor productivity (TFP) growth into technical change, change in technical efficiency and change in scale efficiency. This allows the identification of the sources of productivity growth which is crucial for policy formulation. It was found that the annual TFP growth of the Malaysian manufacturing sector was low at 0.8% and this was driven by small gains in both technical change and technical efficiency, with industries operating close to optimum scale.  相似文献   
73.
对VisualBasic6.0在测控系统软件编程方面的应用进行了探讨,并对其数据处理,I/O操作,动态链接库DLL的编制与调用,数据库管理系统的接口设计、建立、数据格式的转换等方面进行了研究。给出了Windows应用程序建立DLL的方法与步骤,对于在VisualBasic程序中如何应用DLL进行了讨论。  相似文献   
74.
We investigate the determinants of direct office real estate returns by analyzing rents, capital appraisals, and total returns. A recently compiled global database of major cities in Asia, Europe, and the United States provides a unique opportunity to give a macro-view on the effects of economic growth and supply and demand factors on nominal real estate returns. The global database provides quarterly observations from 1986 to 1999. To address the smoothness problem of appraisal-based price data and regulated rents, we employ the Generalized Method of Moments to estimate a dynamic panel-data model. The model allows us to combine the cross-sectional and time-series dimension in our quarterly data. We find that gross domestic product, inflation, unemployment, vacancy rate, and the available stock all have an effect on real estate returns.  相似文献   
75.
本文介绍异步电机空载、短路、负载实验数据处理的数学方法和软件设计方法步骤,形成了实验教学软件。  相似文献   
76.
Correlation estimates for returns between individual properties are subject to large inherent uncertainties due to limits on the amount of data that is likely to be available for the foreseeable future. After allowance for correlation sampling error, it is impossible to distinguish on an ex ante basis between the risk-reduction capabilities of mean-variance portfolio selection models and naive diversification without regard to property type or geographical location. The naive portfolio diversification strategies of typical institutional real estate portfolio managers are rational responses to limitations on the informational content of statistical analyses of historical real estate data.  相似文献   
77.
The inequality in pre-tax income increased in Norway in the 1990s, while the concentration of taxes remained largely unaltered. This means that tax progressivity has decreased in the period, as measured by summary indices of tax progressivity. In this paper I analyze individual income data to ascertain whether tax changes in the period can explain the observed decrease in tax progressivity. As marginal tax rates at high income levels have been substantially reduced in the period, for instance through the tax reform of 1992, it is expected that tax changes may have influenced the degree of inequality in pre-tax incomes. This behavioral effect is examined by deriving estimates of the elasticity of gross income with respect to the net-of-tax rate, obtained from various panel data regressions. The tax changes may also have shifted the distributional burden of taxes for unaltered level of pre-tax income inequality. In order to identify this (direct) effect of tax-law alterations, the same fixed distribution of pre-tax income is exposed to various tax-laws in the period.  相似文献   
78.
This paper examines takeover and divestiture activity at the industry level for the population of UK firms over the period 1986–2000. Consistent with US research, takeovers in the UK cluster both across industries and over time. The evidence for divestitures indicates clustering across industries only. The paper further investigates whether broad and specific industry shocks (e.g., growth, free cash flow, concentration, deregulation, foreign competition, technology, stock market performance) explain takeover and divestiture clustering at the industry level. The results suggest that broad shocks increase (decrease) the likelihood of takeovers (divestitures), although not significantly for takeovers. Specific industry shocks that increase the likelihood of takeover activity include low growth, the threat of foreign competition and high stock market performance. For divestitures, high industry concentration and deregulation increase activity. Little evidence is found for deregulation as a significant factor in explaining takeover activity.  相似文献   
79.
Machine learning techniques make it feasible to calculate claims reserves on individual claims data. This paper illustrates how these techniques can be used by providing an explicit example in individual claims reserving.  相似文献   
80.
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