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In this study, a formula is derived for the period specific beta (market risk) for a portfolio of financial assets that has been formed on the basis of directional forecasts. This is an important contribution to the literature since measuring the risk of an actively managed portfolio is problematic due to the fact that managers may change fund risk conditional on market expectations. The period‐specific nature of the measure is a significant advantage since historical fund returns are not required and the beta is not influenced by prior fund returns' deviations from the bench mark. The methodology employed allows for the development of a time series of fund betas that permits investigation into a number of important empirical issues. This study is also of practical interest from the perspective of risk management and for both portfolio performance and attribution. Finally, there are many active strategies based on directional forecasts and the approach used here encompasses a significant proportion of these.

We examine the stability of market prices for 35 technology and 35 industrial stocks for the period December 31, 1993 to October 31, 2002. A phase portrait plot of the detrended log prices and de‐meaned returns of the two sectors shows a chaotic pattern in the stock prices indicating the presence of nonlinearity. However, when we compute the Lyapunov exponents, negative values are obtained. This shows that the price fluctuations for the 70 stocks result primarily from diffusion processes rather than from nonlinear dynamics. We evaluate forecast errors from a naïve model, a neural network, and ARMA models and find that the forecast errors are correlated with average changes in closed‐end fund discounts and other sentiment indexes. These results support an investor sentiment explanation for the closed‐end fund puzzle and behavioral theories of investor overreaction.

The purpose of this study is to investigate the relationship between predictability in return and investment strategy performance. Two measures that characterize investment strategies within a mean‐variance framework, an activity measure and a style measure, are developed and the performance of alternative strategies (e.g. contrarian, momentum, etc.) is examined when risky asset returns are mean reverting.

Returns are assumed to follow a multivariate Ornstein‐Uhlenbeck process, where reversion to a time‐varying mean is governed by an additional variable set, similar to that proposed by Lo and Wang (1995). Depending on its parameterization, this process is capable of producing an autocorrelation pattern consistent with empirical evidence, that is, positive autocorrelation in short‐horizon returns and negative autocorrelation in long‐horizon returns.

The results, for four uninformed investment strategies and assuming that returns are generated by a simple univariate Ornstein‐Uhlenbeck process, show that the unadjusted returns from the contrarian (momentum) strategy are greater than those from the other strategies when the mean reversion parameter, α, is greater than (less than) one. The results are expected, given the relationship between α and the first‐order autocorrelation in returns. The risk level (measured by either the standard deviation of returns or beta) of the contrarian strategy is the lowest at essentially all levels of mean reversion and the risk‐adjusted returns from the contrarian strategy, measured by the both the Sharpe and Treynor ratios, dominate those from the other strategies.

In future research, a number of issues not considered in this study may be investigated. The style measure developed here can be used to determine whether the results obtained hold when an informed, mean‐variance efficient active strategy is employed. In addition, the performance of both the informed and uninformed strategies may be examined under the assumption that the risky return process follows a multivariate Ornstein‐Uhlenbeck process. This work should provide findings that facilitate the separation of fund risk due to dynamic strategies from that due to time‐varying expected returns.

The methodology used here may be easily extended to consider a number of important issues, such as the frequency of portfolio rebalancing, transactions costs, and multiple asset portfolios, that are encountered in practice.

The approach used here provides insight into how predictability affects the relative performance of tactical investment strategies and, thus, may serve as a basis for determining the magnitude and persistence in autocorrelation required for active investment strategies to yield profits significantly different from those of passive strategies. In this sense, this study may have appeal for both academics and investment professionals.

The purpose of this paper is to provide a literature review of investigations into the specific disability of deafness in the field of sociology and other closely related fields.

After a pilot search using databases appropriate to social science research, we developed key search terms and, using an inductive approach, we identified major themes in the literature.

Our review shows that deafness has been investigated for a long time in sociology and other related fields, that there is a wide range of themes in scholarly work on the experiences of deaf communities and deaf people, and that conceptualizations of deafness and d/Deaf communities have changed over time. We organize this paper around six major themes we identified, and a few highlighted pieces of scholarship illustrate these themes along the way. We particularly focus on scholarship from the late 1960s through the early 1990s as emblematic of seismic shifts in studying deafness, although we do highlight little known nineteenth century work as well.

This paper captures the legacy of this past scholarship and reveals that deafness is a rich site of inquiry that can contribute to the field of sociology. It is also a valuable resource for any future sociological research into deafness, deaf people, and deaf communities. We conclude with a discussion of our findings, commentary on the extent to which previous scholarship on the sociology of deafness has or has not figured into current scholarship and suggestions for future research.

This research aims to design a green pharmaceutical supply chain (PSC) that reduces preventable pharmaceutical waste and effectively disposes of inevitable pharmaceutical waste. The main output of this study is the formulation of an integrated green PSC model involving all critical stakeholders, leading to improved environmental, economic and safety performance in medication management and delivery.

The research is based on literature and on secondary resources.

To green the PSC, every producer of waste is duty bound to facilitate the safe handling and disposal of waste. A cross boundary green PSC (XGPSC) approach is proposed to identify participants' contribution to the PSC. Peripheral influences are also recognised from professional and regulatory bodies.

This study focuses solely on community PSC in the UK where patients receive medication from local community pharmacies and thus may be limited. The proposed XGPSC approach also needs to be tested and validated in practice. It may also be difficult to transfer some of the environmental practices proposed in this research into practice.

The environmental practices and actions proposed provide invaluable insight into various PSC activities, including purchasing, product design, prescription patterns and processes, medication use review, and customer relationship management.

The proposed environmental actions encourage firm commitment from everyone to reduce, recycle or effectively dispose of pharmaceutical waste, with patients becoming stewards of medication rather than only consumers.

A cross boundary approach is developed to green the PSC, which encourages total involvement and collaboration from all participants in PSC.