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A systematic study of earthquake detectability using Sentinel-1 Interferometric Wide-Swath data
Mandatory public benefit reporting as a basis for charity accountability: findings from England & Wales
Charitable status is inherently linked in many jurisdictions with the requirement that an entity must be established for public benefit. But, until recently the public benefit principle had relatively little impact on the operations of most established charities. However, in England and Wales, reforms linked to the Charities Act 2006 led to a new requirement for public benefit reporting in the trusteesā annual report (TAR) of every registered charity. This new narrative reporting requirement had the potential to affect the understanding of accountability by charities. The paper investigates the impact of that requirement through a study of over 1400 sets of charity reports and account
Encoding of low-quality DNA profiles as genotype probability matrices for improved profile comparisons, relatedness evaluation and database searches
Many DNA profiles recovered from crime scene samples are of a quality that
does not allow them to be searched against, nor entered into, databases. We
propose a method for the comparison of profiles arising from two DNA samples,
one or both of which can have multiple donors and be affected by low DNA
template or degraded DNA. We compute likelihood ratios to evaluate the
hypothesis that the two samples have a common DNA donor, and hypotheses
specifying the relatedness of two donors. Our method uses a probability
distribution for the genotype of the donor of interest in each sample. This
distribution can be obtained from a statistical model, or we can exploit the
ability of trained human experts to assess genotype probabilities, thus
extracting much information that would be discarded by standard interpretation
rules. Our method is compatible with established methods in simple settings,
but is more widely applicable and can make better use of information than many
current methods for the analysis of mixed-source, low-template DNA profiles. It
can accommodate uncertainty arising from relatedness instead of or in addition
to uncertainty arising from noisy genotyping. We describe a computer program
GPMDNA, available under an open source license, to calculate LRs using the
method presented in this paper.Comment: 28 pages. Accepted for publication 2-Sep-2016 - Forensic Science
International: Genetic
Off-resonance magnetisation transfer contrast (MTC) MRI using fast field-cycling (FFC)
Peer reviewedPostprin
Integration of psychological models in the design of artificial creatures
Artificial creatures form an increasingly important component of interactive computer games. Examples of such creatures exist which can interact with each other and the game player and learn from their experiences. However, we argue, the design of the underlying architecture and algorithms has to a large extent overlooked knowledge from psychology and cognitive sciences. We explore the integration of observations from studies of motivational systems and emotional behaviour into the design of artificial creatures. An initial implementation of our ideas using the āsim agentā toolkit illustrates that physiological models can be used as the basis for creatures with animal like behaviour attributes. The current aim of this research is to increase the ārealismā of artificial creatures in interactive game-play, but it may have wider implications for the development of AI
Stability of Noisy Metropolis-Hastings
Pseudo-marginal Markov chain Monte Carlo methods for sampling from
intractable distributions have gained recent interest and have been
theoretically studied in considerable depth. Their main appeal is that they are
exact, in the sense that they target marginally the correct invariant
distribution. However, the pseudo-marginal Markov chain can exhibit poor mixing
and slow convergence towards its target. As an alternative, a subtly different
Markov chain can be simulated, where better mixing is possible but the
exactness property is sacrificed. This is the noisy algorithm, initially
conceptualised as Monte Carlo within Metropolis (MCWM), which has also been
studied but to a lesser extent. The present article provides a further
characterisation of the noisy algorithm, with a focus on fundamental stability
properties like positive recurrence and geometric ergodicity. Sufficient
conditions for inheriting geometric ergodicity from a standard
Metropolis-Hastings chain are given, as well as convergence of the invariant
distribution towards the true target distribution
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