23 research outputs found

    Heteroscedasticity and interval effects in estimating beta: UK evidence

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    The article compares beta estimates obtained from Ordinary Least Squares (OLS) regression with estimates corrected for heteroscedasticity of the error term using Autoregressive Conditional Heteroscedasticity (ARCH) models, for 145 UK shares. The differences are mainly less than 0.10, for betas calculated using daily returns, but even such small differences can matter in practice. OLS tends to overestimate the beta coefficients compared with ARCH models, and selecting an ARCH type estimate makes the most difference for large cap shares. Regarding the measurement interval, the downward bias in betas from daily returns is associated with not only thin trading but also the volatility of the share's daily returns. We infer that the idiosyncratic component in daily returns, as well as lack of trading, is responsible for low daily betas.beta estimation, heteroscedasticity, ARCH models, interval effect,

    Preparing for the ‘real’ market: national patterns of institutional learning and company behaviour in the European Emissions Trading Scheme (EU ETS)

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    European companies have reacted in different ways to the European Emissions Trading Scheme (EU ETS), Phase I. While some companies engaged in an active trading behaviour focused on additional revenues, others adopted a strategy orientated to mere compliance with the scheme and aimed for balanced accounts only. This article provides the outcomes of a survey on company behaviour under the EU ETS in Germany, the United Kingdom, the Netherlands and Denmark from 2005 to 2006, in which cross-national differences in trading behaviour are linked to national patterns of policy implementation and the political economies in which companies operate. Thus, specific country patterns of institutional preparation and institutional learning for the ‘real’ CO2 allowance market in Phase II of the EU ETS (2008–2012) are sketched. Whereas Phase I is distinguished by a net over-allocation of allowances, Phase II is expected to entail some level of scarcity of allowances. We argue that companies are prepared differently to meet the challenges of the future EU ETS. Copyright © 2008 John Wiley Sons, Ltd and ERP Environment
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