Khat-chewing in liminal leisure spaces: British-Somali youth on the margins

Khat-chewing, a controversial leisure activity within the Somali diaspora in Britain, has received little attention within the academic field of Leisure Studies. This paper reports on ethnographic research to provide insights into the unique locations where young British-Somali men chew khat, exposing the liminal qualities of such localities. The paper begins with an overview of the contentious position khat-chewing occupies within Somali communities in Britain, highlighting reasons why young British-Somali men hide their association with the leisure practice. The discussion that follows considers how young male khat users conceptualise spatial environments, exposing how these locations temporarily produce a dual sense of privacy and sociality. The ambiences of such temporary leisure spaces remain open to the prospect of discovery, resulting in the use of discretionary tactics to maintain a sense of secrecy. In this context, we discuss how khat-chewing offers a sense of cultural identity and belongingness while also marking young British-Somali men as outsiders – even within their own communities.     

Combining information for prediction in linear regression

This article deals with the prediction problem in linear regression where the measurements are obtained using k different devices or collected from k different independent sources. For the case of k=2, a Graybill-Deal type combined estimtor for the regression parameters is shown to dominate the individual least squares estimators under the covariance criterion. Two predictors ŷ _c and ŷ _p are proposed. ŷ _c is based on a combined estimator of the regression coefficient vector, and ŷ _p is obtained by combining the individual predictors from different models. Prediction mean square errors of both predictors are derived. It is shown that the predictor ŷ _p is better than the individual predictors for k≥2 and the predictor ŷ _c is better than the individual predictors for k=2. Numerical comparison between ŷ _c and ŷ _p shows that the former is superior to the latter for the case k=2.     

Estimating daily volatility in financial markets utilizing intraday data

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.     

Railways and the Exploitation of Victoria's Forests, 1880s–1920s

Railways made a large contribution to the expansion of Victoria's economy, and in the process enabled and drove environmental change. This article focuses on one industry, forestry. It first examines railway demand for timber in construction and maintenance, particularly for sleepers. This demand caused tensions – a bitter dispute in the 1890s between the Railways Department and the Conservator of Forests, George Perrin, over timber cut on state land led to uneasy co-existence after the turn of the century. Railways not only required timber but also carried commercial quantities in bulk, providing forest industries with access to profitable markets – in particular firewood, the significance of which has been underappreciated previously. Forest products contributed substantially to railway revenue, representing a more stable source of income than other major categories of freight such as wheat, wool, and coal.     

Relationship between positive psychological capital and creative performance

Despite considerable attention to the creative process and its relationship with personal characteristics, there is no published study focused directly on the relationship between the recently recognized core construct of psychological capital (PsyCap) and creative performance. Drawing from a large (N = 899) and heterogeneous sample of working adults, this study investigates PsyCap and its components (i.e., efficacy, hope, optimism, and resilience) as predictors of creative performance. Overall PsyCap predicted creative performance over and above each of the four PsyCap components. Theoretical and practical implications of these findings are considered. Copyright © 2010 ASAC. Published by John Wiley & Sons, Ltd.     

Backcasting energy futures using industrial ecology

Backcasting has been widely used for developing energy futures. This paper explores the potential for using industrial ecology to guide the development of energy futures within a backcasting framework. Building on the backcasting work of Robinson [1], a seven step method is presented to embed industrial ecology principles within the development and assessment of future scenarios and transition paths toward them. The approach is applied to the case of backcasting regional energy futures in the Latrobe Valley, near Melbourne, Australia. This region has substantial brown coal deposits which are currently mined and used in coal-fired power stations to generate electricity. Bounded by a sustainability vision for the region in a carbon-constrained world, regional industrial ecologies in 2050 were backcast around three themes: bio-industries and renewables (no coal usage); electricity from coal with carbon capture and storage (low to high coal usage); and coal to products such as hydrogen, ammonia, diesel, methanol, plastics and char (demonstrating medium to high overall coal use relative to current levels). Potential environmental, technological, socio-political and economic impacts of each scenario across various life cycle stages were characterised. Results offer a platform for regional policy development to underpin deliberation on a preferred future by the community, industry and other stakeholders. Industrial ecology principles were found to be useful in backcasting for creatively articulating alternative futures featuring industrial symbiosis. However, enabling the approach to guide implementation of sustainable transition pathways requires further development and would benefit from integration within the Strategic Sustainable Development framework of Robèrt et al. [2].     

该把钱交给私募基金公司吗?

具有传奇性的私募基金公司Kohlberg Kravis Roberts将要在纽约证券交易所上市了。Oppenheimer & Co.公司的分析师克里斯·可特维斯基(Chris Kotowski)在最近发表的一份报告中写道,私募基金公司目前被视为是一种‘昙花一现'的怪物,对其财务和交易史人们知之甚少。但随着时间的推移,这种情况会有所改变。