Public understanding of regimes of risk regulation: Focus groups with citizens and consumers

This report investigates the nature of public understanding of risk and regulation. Issues of risk and regulation are both significant for the public and recognised as such by them. It shows that the public has strong and diverse views on the regulation of the risks they face in their daily lives, and is often critical of the ways in which risks are managed. This raises key issues for regulators and other stakeholders concerned with risk management, public awareness and consumer rights and responsibilities. As part of the ESRC-funded research project, Public Understanding of Regimes of Risk Regulation, part of the SCARR network, the authors conducted sixteen focus groups with a cross-section of the UK public. The discussions ranged across risk and regulation issues broadly, though two sectors - communications and financial services – were explored in detail

Adaptive MBER space-time DFE assisted multiuser detection for SDMA systems

In this contribution we propose a space-time decision feedback equalization (ST-DFE) assisted multiuser detection (MUD) scheme for multiple antenna aided space division multiple access systems. A minimum bit error rate (MBER) design is invoked for the MUD, which is shown to be capable of improving the achievable bit error rate performance over that of the minimum mean square error (MMSE) design. An adaptive MBER ST-DFE-MUD is proposed using the least bit error rate algorithm, which is demonstrated to consistently outperform the least mean square (LMS) algorithm, while achieving a lower computational complexity than the LMS algorithm for the binary signalling scheme. Simulation results demonstrate that theMBER ST-DFE-MUD is more robust to channel estimation errors as well as to error propagation imposed by decision feedback errors, compared to the MMSE ST-DFE-MUD

Minimum Bit-Error Rate Design for Space-Time Equalisation-Based Multiuser Detection

A novel minimum bit-error rate (MBER) space–time equalization (STE)-based multiuser detector (MUD) is proposed for multiple-receive-antenna-assisted space-division multiple-access systems. It is shown that the MBER-STE-aided MUD significantly outperforms the standard minimum mean-square error design in terms of the achievable bit-error rate (BER). Adaptive implementations of the MBER STE are considered, and both the block-data-based and sample-by-sample adaptive MBER algorithms are proposed. The latter, referred to as the least BER (LBER) algorithm, is compared with the most popular adaptive algorithm, known as the least mean square (LMS) algorithm. It is shown that in case of binary phase-shift keying, the computational complexity of the LBER-STE is about half of that required by the classic LMS-STE. Simulation results demonstrate that the LBER algorithm performs consistently better than the classic LMS algorithm, both in terms of its convergence speed and steady-state BER performance. Index Terms—Adaptive algorithm, minimum bit-error rate (MBER), multiuser detection (MUD), space–time processing

HIV/AIDS Pandemic in Africa: Trends and Challenges

Three-quarters of the world’s AIDS population lives in Sub-Saharan Africa; most have no access to lifesaving drugs, testing facilities or even basic preventative health care. One of the major factors inhibiting medical professionals in Africa from treating this disease is the inability to access vast areas of the continent with adequately equipped medical facilities. To meet this need, Architecture for Humanity challenged the world’s architects and health care professionals to submit designs for a mobile HIV/AIDS health clinic. The pandemic is changing the demographic structure of Africa and wiping out life expectancy gains. Indeed, in many African countries, life expectancy is dropping from more than 60 years to around 45 years or even less. In this paper, we highlight the uniqueness of factors associated with HIV/AIDS pandemic in Africa and present its impact and challenges.HIV/AIDS, Africa

The Meaning of Collaborative Research

Summary This article examines the prospects for inter?country collaborative research between academic institutions of greatly varying experience and resources, and notes the case for unilateral action by research institutes in poor countries which have suffered the domination of rich and powerful foreign research interests. Some criteria are suggested for assessing the readiness of research institutions in any part of the world to cooperate effectively. The question is left open as to whether we possess or are likely to acquire the capacity to collaborate successfully across barriers of history and contemporary events. Resume Signification de la recherche en collaboration Cet article examine les perspectives relatives à la recherche inter?pays impliquant la collaboration d'institutions académiques ayant une expérience et des ressources extrémement variées, et il cite l'argument en faveur de l'action unilatérale par des instituts de recherche dans les pays pauvres qui ont subi la domination d'intérêts de recherche étrangers riches et puissants. Plusieurs critères sont suggérés pour déterminer si les institutions de recherche en n'importe quel coin du monde sont prêtes à collaborer efficacement. Il n'est pas donné de réponse à la question de savoir si nous avons ou sommes susceptibles d'acquérir l'aptitude à collaborer efficacement malgré les barrières de l'histoire et des événements contemporaines. Resumen El significado de la investigación colaborativa En el artículo se examinan las perspectivas para la investigación colaborativa entre países, a través de las instituciones académicas de experiencia y recursos muy variables, y pone de relieve la oportunidad de adoptar una acción unilateral por parte de institutos de investigación en países pobres que han sufrido el dominio de intereses de investigación extranjera potentes y ricos. Se sugieren ciertos criterios para evaluar la preparación de las instituciones de investigación en cualquier parte del mundo con objeto de cooperar de manera eficaz. Queda por saber si poseemos o es probable que consigamos adquirir la capacidad de colaborar con éxito a través de barreras históricas y acontecimientos contemporáneos

The Barker proposal: Combining robustness and efficiency in gradient-based MCMC

There is a tension between robustness and efficiency when designing Markov chain Monte Carlo (MCMC) sampling algorithms. Here we focus on robustness with respect to tuning parameters, showing that more sophisticated algorithms tend to be more sensitive to the choice of step-size parameter and less robust to heterogeneity of the distribution of interest. We characterise this phenomenon by studying the behaviour of spectral gaps as an increasingly poor step-size is chosen for the algorithm. Motivated by these considerations, we propose a novel and simple gradient-based MCMC algorithm, inspired by the classical Barker accept-reject rule, with improved robustness properties. Extensive theoretical results, dealing with robustness to tuning, geometric ergodicity and scaling with dimension, suggest that the novel scheme combines the robustness of simple schemes with the efficiency of gradient-based ones. We show numerically that this type of robustness is particularly beneficial in the context of adaptive MCMC, giving examples where our proposed scheme significantly outperforms state-of-the-art alternatives

Explaining reactions to normative information about alcohol consumption: A test of an extended social identity model

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordBackground: To test the role of group identification and the perceived importance of alcohol consumption to a group identity in shaping reactions to normative information about alcohol consumption. Methods: The study had a 2 (behaviour: identity-defining/alcohol vs. non-identity defining/caffeine). ×. 2 (norm: low vs. heavy consumption) between-subjects factorial design. Group identification and personal attitudes towards alcohol/caffeine consumption were included as measured predictors. Participants were 83 undergraduate students (44 female, 38 male, one unspecified) at a University in Scotland. Predictor and outcome variables included questionnaire measures of group (student) identification, personal attitudes to alcohol/caffeine consumption, the perceived importance of alcohol/caffeine consumption to group identity, and behavioral intentions to consume alcohol/caffeine. Results: Personal attitude and group identification moderated the impact of norm information on consumption intentions, but only for alcohol consumption, and not caffeine consumption. For alcohol, norm information did affect intended consumption (ps. ≤.034), with the crucial exception of high identifiers who had favourable personal attitudes towards alcohol consumption. Instead, these individuals resist norm information (ps = .458 and.174), showing no decrease in intentions in the face of norm information that emphasised relatively 'low' levels of consumption. Conclusions: The impact of norm information on alcohol consumption intentions depends on group-based factors such as group identification and the perceived importance of alcohol to a group identity. When both of these factors are high, and an individual also personally favours the behaviour, the potential for norm-based interventions to fail is increased

Peskun–Tierney ordering for Markovian Monte Carlo: Beyond the reversible scenario

Historically time-reversibility of the transitions or processes underpinning Markov chain Monte Carlo methods (MCMC) has played a key role in their development, while the self-adjointness of associated operators together with the use of classical functional analysis techniques on Hilbert spaces have led to powerful and practically successful tools to characterise and compare their performance. Similar results for algorithms relying on nonreversible Markov processes are scarce. We show that for a type of nonreversible Monte Carlo Markov chains and processes, of current or renewed interest in the physics and statistical literatures, it is possible to develop comparison results which closely mirror those available in the reversible scenario. We show that these results shed light on earlier literature, proving some conjectures and strengthening some earlier results