6,561 research outputs found
UK Business Investment: Long-Run Elasticities and Short-Run Dynamics
From neoclassical theory output, capital stock and the user cost are cointegrated; capital and investment also (multi)cointegrate through the capital accumulation identity. An investment equation is estimated on UK data using a new capital stock series and a long series for the weighted cost of capital. Assuming CES technology, the elasticity of substitution is well-determined and below unity. Over-identifying restrictions are accepted. The long-run parameter is robust to alternative specifications, but single-equation investment relationships may obscure the dynamics. The Johansen method is over-sized, but outperforms a single equation test for excluding the capital accumulation identity from the investment equation.investment, capital stock, identification, multicointegration
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Rethinking Models of Evaluation: Sustainability as the Goal of International Cultural Organisations
The purpose and conduct of organisational evaluation is variously defined and understood. With the shift to the ‘new managerialism’ and the steady advance of audit culture in the public sector, evaluation models have proliferated but they are often narrowed to crude measures of impact and performance. They subject people to unhelpful, top-down forms of appraisal and accountability in the interests of transparency and economic efficiency with little respect afforded to the multiple perspectives and divergent goals of the actors involved. There is often a lack of clarity about what is being evaluated and from whose perspective.
This paper traces the development of the Cultural Value Model (CVM). It was developed as part of UK-wide research programme aimed at rethinking how we assess the value of cultural activities. The primary objective of the CVM is to provide an analytical and methodological framework for re-conceiving models of evaluation. In particular, it shifts the frame of analysis away from impact to value. Our project aimed to deliver a robust, evidence-based understanding of the changing cultural value of the British Council (BC) and BBC World Service (BBCWS). These publically funded international organisations are an integral part of the UK’s diplomatic infrastructure and subject to stringent accountability measures to satisfy diverse stakeholders. They are experiencing rapid and convulsive change in response to financial, technological and geopolitical forces and their purpose and value is being questioned.
In the paper we argue that the CVM, in fostering a more engaged, participatory approach to performance evaluation challenged and even subverted existing practices but with mixed results. In the case of the BC, it generated a high degree of interest and engagement to the extent that it is currently being adopted and integrated into organisational practices. In contrast, the BBCWS were more resistant to innovation believing that their audience ratings and internal reviews suffice. The flexible adaptability of the CVM presents an opportunity for other organisations to move from away from top-down performance and impact assessment towards a more inclusive, reflective and sustainable model of value. However we need to get a better understanding the organisational constraints that obstruct innovation if more participatory models of learning, monitoring and evaluation are to intervene in social and organisational processes and achieve sustainable models of good practice
Ensemble Transport Adaptive Importance Sampling
Markov chain Monte Carlo methods are a powerful and commonly used family of
numerical methods for sampling from complex probability distributions. As
applications of these methods increase in size and complexity, the need for
efficient methods increases. In this paper, we present a particle ensemble
algorithm. At each iteration, an importance sampling proposal distribution is
formed using an ensemble of particles. A stratified sample is taken from this
distribution and weighted under the posterior, a state-of-the-art ensemble
transport resampling method is then used to create an evenly weighted sample
ready for the next iteration. We demonstrate that this ensemble transport
adaptive importance sampling (ETAIS) method outperforms MCMC methods with
equivalent proposal distributions for low dimensional problems, and in fact
shows better than linear improvements in convergence rates with respect to the
number of ensemble members. We also introduce a new resampling strategy,
multinomial transformation (MT), which while not as accurate as the ensemble
transport resampler, is substantially less costly for large ensemble sizes, and
can then be used in conjunction with ETAIS for complex problems. We also focus
on how algorithmic parameters regarding the mixture proposal can be quickly
tuned to optimise performance. In particular, we demonstrate this methodology's
superior sampling for multimodal problems, such as those arising from inference
for mixture models, and for problems with expensive likelihoods requiring the
solution of a differential equation, for which speed-ups of orders of magnitude
are demonstrated. Likelihood evaluations of the ensemble could be computed in a
distributed manner, suggesting that this methodology is a good candidate for
parallel Bayesian computations
Chronic helminth infection burden differentially affects haematopoietic cell development while ageing selectively impairs adaptive responses to infection
Throughout the lifespan of an individual, the immune system undergoes complex changes while facing novel and chronic infections. Helminths, which infect over one billion people and impose heavy livestock productivity losses, typically cause chronic infections by avoiding and suppressing host immunity. Yet, how age affects immune responses to lifelong parasitic infection is poorly understood. To disentangle the processes involved, we employed supervised statistical learning techniques to identify which factors among haematopoietic stem and progenitor cells (HSPC), and both innate and adaptive responses regulate parasite burdens and how they are affected by host age. Older mice harboured greater numbers of the parasites’ offspring than younger mice. Protective immune responses that did not vary with age were dominated by HSPC, while ageing specifically eroded adaptive immunity, with reduced numbers of naïve T cells, poor T cell responsiveness to parasites, and impaired antibody production. We identified immune factors consistent with previously-reported immune responses to helminths, and also revealed novel interactions between helminths and HSPC maturation. Our approach thus allowed disentangling the concurrent effects of ageing and infection across the full maturation cycle of the immune response and highlights the potential of such approaches to improve understanding of the immune system within the whole organism
How are normal sleeping controls selected? A systematic review of cross-sectional insomnia studies, and a standardised method to select healthy controls for sleep research
There appears to be some inconsistency in how normal sleepers (controls) are selected and screened for participation in research studies for comparison with insomnia patients. The purpose of the current study is to assess and compare methods of identifying normal sleepers in insomnia studies, with reference to published standards. We systematically reviewed the literature on insomnia patients which included control subjects. The resulting 37 articles were systematically reviewed with reference to the five criteria for normal sleep specified by Edinger et al. (2004). In summary, these criteria are: evidence of sleep disruption; sleep scheduling; general health; substance/medication use; and other sleep disorders. We found sleep diaries, PSG, and clinical screening examinations to be widely used with both control subjects and insomnia participants. However, there are differences between research groups in the precise definitions applied to the components of normal sleep. We found that none of reviewed studies applied all of the Edinger et al. criteria, and 16% met four criteria. In general, screening is applied most rigorously at the level of a clinical disorder, whether physical, psychiatric, or sleep. While the Edinger et al. criteria seem to be applied in some form by most researchers, there is scope to improve standards and definitions in this area. Ideally, different methods such as sleep diaries and questionnaires would be used concurrently with objective measures to ensure normal sleepers are identified, and descriptive information for control subjects would be reported. Here, we have devised working criteria and methods to be used for assessment of normal sleepers. This would help clarify the nature of the control group, in contrast to insomnia subjects and other patient groups
Social interactions, emotion and sleep: a systematic review and research agenda
Sleep and emotion are closely linked, however the effects of sleep on socio-emotional task performance have only recently been investigated. Sleep loss and insomnia have been found to affect emotional reactivity and social functioning, although results, taken together, are somewhat contradictory. Here we review this advancing literature, aiming to 1) systematically review the relevant literature on sleep and socio-emotional functioning, with reference to the extant literature on emotion and social interactions, 2) summarize results and outline ways in which emotion, social interactions, and sleep may interact, and 3) suggest key limitations and future directions for this field. From the reviewed literature, sleep deprivation is associated with diminished emotional expressivity and impaired emotion recognition, and this has particular relevance for social interactions. Sleep deprivation also increases emotional reactivity; results which are most apparent with neuro-imaging studies investigating amygdala activity and its prefrontal regulation. Evidence of emotional dysregulation in insomnia and poor sleep has also been reported. In general, limitations of this literature include how performance measures are linked to self-reports, and how results are linked to socio-emotional functioning. We conclude by suggesting some possible future directions for this field
European leadership in 5G. CEPS Special Report, December 2016
Prepared by Policy Department A at the request of the European Parliament’s
Committee on Industry, Research and Energy (ITRE), this report examines the
concept for 5G, how it might fit in the future telecommunications landscape, the
state of play in R&D in the EU and globally, the possible business models and the
role of standards and spectrum policy, to assess the EU’s strategic position
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