Results in Optimal Discrimination

We study the problem of discriminating between non-orthogonal quantum states with least probability of error. We demonstrate that this problem can be simplified if we solve for the error itself rather than solving directly for the optimal measurement. This method enables us to derive solutions directly and thus make definite statements about the uniqueness of an optimal strategy. This approach immediately leads us to a state-discrimination analogue of Davies Theorem. In the course of this, a complete solution for distinguishing equally likely pure qubit states is presented.Comment: 4 pages, 1 figure. To appear in the Proceedings of QCMC0

Maximum fidelity retransmission of mirror symmetric qubit states

In this paper we address the problem of optimal reconstruction of a quantum state from the result of a single measurement when the original quantum state is known to be a member of some specified set. A suitable figure of merit for this process is the fidelity, which is the probability that the state we construct on the basis of the measurement result is found by a subsequent test to match the original state. We consider the maximisation of the fidelity for a set of three mirror symmetric qubit states. In contrast to previous examples, we find that the strategy which minimises the probability of erroneously identifying the state does not generally maximise the fidelity

Measurement does not always aid state discrimination

We have investigated the problem of discriminating between nonorthogonal quantum states with least probability of error. We have determined that the best strategy for some sets of states is to make no measurement at all, and simply to always assign the most commonly occurring state. Conditions which describe such sets of states have been derived.Comment: 3 page

Exploring the utility of the Multidimensional State Boredom Scale.

Background: State boredom–the experience of boredom in the moment – is related to a number of psychosocial issues. Until the recent creation of the Multidimensional State Boredom Scale (MSBS), research was constrained by the lack of a comprehensive, validated measure. However, the MSBS could benefit from further evaluation. Aim: To more thoroughly validate the MSBS. Methods: In two studies, participants were induced into a state of either boredom or non-boredom, and then completed the MSBS. Results: Discriminant analysis showed that the full MSBS was able to correctly classify 68.1% (Study 2) – 84.1% (Study 1) of participants into their experimental condition. Based on 14 further DA analysis, a subset of eight items (a potential short form) is proposed. Differential item functioning (Study 1) found only one item to which responding differed by gender. Discussion: Use of the MSBS, including the full scale versus the short form, is discussed. Which experiential components of boredom may be particularly important for classifying bored individuals, and the issue of variability across boredom manipulations, are also considered

Examination of differential ratings of perceived exertion (dRPE) during bio-banded small-sided games.

The aims of the current study were to investigate the use of dRPE with academy soccer players to: 1) examine the effect of bio-banded and non-bio-banded maturity groups within SSG on players dRPE; 2) describe the multivariate relationships between dRPE measures investigating the sources of intra and inter-individual variation, and the effects of maturation and bio-banding. Using 32 highly trained under (U) 12 to U14 soccer players (mean (SD) age 12.9 (0.9) years, body mass 46.4 (8.5) kg and stature 158.2 (14.9) cm) academy soccer players from two English professional male soccer academies. Players were categorised according to somatic maturity status using estimated percentage of adult stature attainment, with players randomly assigned into teams to play 4v4 SSG. The study used a repeated measures design, whereby the selected players participated within 6 bio-banded (maturity matched [pre-PHV Vs pre-PHV and post-PHV vs post PHV] and miss-matched [pre-PHV vs post-PHV] and 6 mixed maturity SSG at their respective clubs. Using mixed and fixed effect regression models, it was established hat pre-PHV players exhibited higher dRPE compared with their post-PHV counterparts. Mixed bio-banded games reported higher dRPE outputs overall. Variation in dRPE measures across a series of bio-banded games are caused by both between and within sources of variation in relatively equal amounts. Across a series of bio-banded games, the four dRPE measures do not provide unique information, and between variation is best expressed by one or two highly correlated components, with within variation best explained by a single equally loaded component. Using a bio-banding SSG design study, we have shown that pre-PHV players report higher subjective measures of exertion than post-PHV players during. Additionally, when evenly mixing players based on measures of maturation, higher measures of perceived exertion were generally reported

Public attitudes to, and perceived impacts of 20mph (32 km/h) speed limits in Edinburgh:An exploratory study using the Speed Limits Perceptions Survey (SLiPS)

The ‘Is 20 plenty for health?’ study is funded by a National Institute for Health Research (NIHR) Public Health Research (PHR) grant 15/82/12.Between 2016 and 2018 a policy was implemented to increase the proportion of 20mph (32km/h) streets in Edinburgh, UK from approximately 50% to 80%, providing the opportunity to evaluate how behaviour and public perceptions change over time. This is important as negative public responses have been reported to limit the implementation of transport policies and may reduce the effectiveness of the policy. The Speed Limits Perception Survey (SLiPS) was developed to assess changes in public perceptions from baseline to 6 and 12 months post-implementation. We collected 3,485 individual responses to the survey, 64.6% (n = 2,253) of which included complete perceptions data. Using exploratory factor analysis, the following perception factors were identified: i) Detraction and resistance, ii) Support, iii) Rule following, iv) Child safety, and v) Walking safety. Following the 20mph implementation at 6–12 months: Support (ii) and Rule following (iii) had increased; Detraction and resistance (i) had decreased; and Child safety (iv) and Walking safety (v) had not changed significantly. These findings indicate that the public in Edinburgh became more positive towards the policy once it was implemented. However, more extensive policy or ongoing communication of the safety benefits of 20mph limits are needed to increase perceptions of safety that might lead to increased walking and cycling. Future research should aim to understand how those implementing speed limit interventions can positively influence public perceptions and how public perceptions about speed limits influence behaviour.Publisher PDFPeer reviewe

Survivor-informed support for trafficked children in Scotland: Full report

Kieran Taylor - ORCID: 0009-0005-2392-1747 https://orcid.org/0009-0005-2392-1747Ensuring better outcomes for children and young people who have experienced human trafficking is a major and urgent challenge facing the UK. While the exploitation experiences and immediate support needs of children who have experienced trafficking are well documented in research, the evidence base on what happens in the longer term for children and young people – and how they feel about it – is more limited. Most evaluations of support provision focus on stories of trafficking and needs immediately after identification. Once children and young people move beyond this stage, the spotlight on them fades. This study sought to extend the timeframe to explore short, medium and longterm experiences of recovery. The study directly involved children and young people who had made their homes in the UK, eliciting narratives of recovery with a focus on their choices as well as needs, alongside data recorded by, or gathered from, professionals. The aim was to improve understanding of what constitutes sustainable support over a longer timeframe, thus offering valuable insights for all those working with this group of children and young people, in the UK and internationally.Funded by the Modern Slavery and Human Rights Policy and Evidence Centre (Modern Slavery PEC), which in turn is funded and supported by the UK Arts and Humanities Research Council (AHRC)https://modernslaverypec.org/resources/trafficked-children-scotlandpubpu

Minimum-error discrimination between three mirror-symmetric states

We present the optimal measurement strategy for distinguishing between three quantum states exhibiting a mirror symmetry. The three states live in a two-dimensional Hilbert space, and are thus overcomplete. By mirror symmetry we understand that the transformation {|+> -> |+>, |-> -> -|->} leaves the set of states invariant. The obtained measurement strategy minimizes the error probability. An experimental realization for polarized photons, realizable with current technology, is suggested.Comment: 4 pages, 2 figure

Use of natural experimental studies to evaluate 20mph speed limits in two major UK cities.

INTRODUCTION: Reductions in traffic speed can potentially offer multiple health and public health benefits. In 2016, implementation of 20mph (30kph) speed limit interventions began in Edinburgh (city-wide) and Belfast (city centre). The aims of this paper are to describe 1) the broad theoretical approach and design of two natural experimental studies to evaluate the 20mph speed limits in Edinburgh and Belfast and 2) how these studies allowed us to test and explore theoretical mechanisms of 20mph speed limit interventions. METHODS: The evaluation consisted of several work packages, each with different research foci, including the political decision-making processes that led to the schemes, their implementation processes, outcomes (including traffic speed, perceptions of safety, and casualties) and cost effectiveness. We used a combination of routinely and locally collected quantitative data and primary quantitative and qualitative data. RESULTS: The evaluation identified many contextual factors influencing the likelihood of 20mph speed limits reaching the political agenda. There were substantial differences between the two sites in several aspects related to implementation. Reductions in speed resulted in significant reductions in collisions and casualties, particularly in Edinburgh, which had higher average speed at baseline. The monetary value of collisions and casualties prevented are likely to exceed the costs of the intervention and thus the overall balance of costs and benefits is likely to be favourable. CONCLUSIONS: Innovative study designs, including natural experiments, are important for assessing the impact of 'real world' public health interventions. Using multiple methods, this project enabled a deeper understanding of not only the effects of the intervention but the factors that explain how and why the intervention and the effects did or did not occur. Importantly it has shown that 20mph speed limits can lead to reductions in speed, collisions and casualties, and are therefore an effective public health intervention