Using the EQ-5D as a performance measurement tool in the NHS

In a landmark move, the UK Department of Health (DH) is introducing the routine use of Patient Reported Outcome Measures (PROMs) as a means of measuring the performance of health care providers in improving patient health. From April 2009 all patients will be asked to complete both generic (EQ-5D) and condition specific PROMs before and after surgery for four elective procedures; the intention is to extend this to a wide range of other NHS services. The aim of this paper is to report analysis of the EQ-5D data generated from a pilot study commissioned by the DH, and to consider the implications of the results for their use as performance indicators and measures of patient benefit. The EQ-5D has the potential advantage in the context of PROMs of enabling comparisons of performance across services as well as between providers; and in facilitating assessments of the cost effectiveness of NHS services. We present two new methods we have developed for analysing and displaying EQ-5D profile data: a Paretian Classification of Health Change, and a Health Profile Grid. Using these methods, we show that EQ-5D data can readily be used to generate useful insights into differences between providers in improving overall changes in health; results are also suggestive of striking differences in changes in health between surgical procedures. We conclude by noting a number of issues that remain to be addressed in the use of PROMs data as a basis for performance indicators

Improving efficiency in radio surveys for gravitational lenses

Many lens surveys have hitherto used observations of large samples of background sources to select the small minority which are multiply imaged by lensing galaxies along the line of sight. Recently surveys such as SLACS and OLS have improved the efficiency of surveys by pre-selecting double-redshift systems from SDSS. We explore other ways to improve survey efficiency by optimum use of astrometric and morphological information in existing large-scale optical and radio surveys. The method exploits the small position differences between FIRST radio positions of lensed images and the SDSS lens galaxy positions, together with the marginal resolution of some larger gravitational lens systems by the FIRST beam. We present results of a small pilot study with the VLA and MERLIN, and discuss the desirable criteria for future surveys.Comment: Accepted by MNRAS. 9 pages, 5 figure

Finding Optimal Flows Efficiently

Among the models of quantum computation, the One-way Quantum Computer is one of the most promising proposals of physical realization, and opens new perspectives for parallelization by taking advantage of quantum entanglement. Since a one-way quantum computation is based on quantum measurement, which is a fundamentally nondeterministic evolution, a sufficient condition of global determinism has been introduced as the existence of a causal flow in a graph that underlies the computation. A O(n^3)-algorithm has been introduced for finding such a causal flow when the numbers of output and input vertices in the graph are equal, otherwise no polynomial time algorithm was known for deciding whether a graph has a causal flow or not. Our main contribution is to introduce a O(n^2)-algorithm for finding a causal flow, if any, whatever the numbers of input and output vertices are. This answers the open question stated by Danos and Kashefi and by de Beaudrap. Moreover, we prove that our algorithm produces an optimal flow (flow of minimal depth.) Whereas the existence of a causal flow is a sufficient condition for determinism, it is not a necessary condition. A weaker version of the causal flow, called gflow (generalized flow) has been introduced and has been proved to be a necessary and sufficient condition for a family of deterministic computations. Moreover the depth of the quantum computation is upper bounded by the depth of the gflow. However, the existence of a polynomial time algorithm that finds a gflow has been stated as an open question. In this paper we answer this positively with a polynomial time algorithm that outputs an optimal gflow of a given graph and thus finds an optimal correction strategy to the nondeterministic evolution due to measurements.Comment: 10 pages, 3 figure

NICMOS and VLBA observations of the gravitational lens system B1933+503

NICMOS observations of the complex gravitational lens system B1933+503 reveal infrared counterparts to two of the inverted spectrum radio images. The infrared images have arc-like structures. The corresponding radio images are also detected in a VLBA map made at 1.7 GHz with a resolution of 6 mas. We fail to detect two of the four inverted radio spectrum components with the VLBA even though they are clearly visible in a MERLIN map at the same frequency at a different epoch. The absence of these two components could be due to rapid variability on a time-scale less than the time delay, or to broadening of the images during propagation of the radio waves through the ISM of the lensing galaxy to an extent that they fall below the surface brightness detectability threshold of the VLBA observations. The failure to detect the same two images with NICMOS is probably due to extinction in the ISM of the lensing galaxy.Comment: 5 pages, 4 figures, submitted to MNRA

Biasing MCTS with Features for General Games

This paper proposes using a linear function approximator, rather than a deep neural network (DNN), to bias a Monte Carlo tree search (MCTS) player for general games. This is unlikely to match the potential raw playing strength of DNNs, but has advantages in terms of generality, interpretability and resources (time and hardware) required for training. Features describing local patterns are used as inputs. The features are formulated in such a way that they are easily interpretable and applicable to a wide range of general games, and might encode simple local strategies. We gradually create new features during the same self-play training process used to learn feature weights. We evaluate the playing strength of an MCTS player biased by learnt features against a standard upper confidence bounds for trees (UCT) player in multiple different board games, and demonstrate significantly improved playing strength in the majority of them after a small number of self-play training games.Comment: Accepted at IEEE CEC 2019, Special Session on Games. Copyright of final version held by IEE

The Serendiptichord: Reflections on the collaborative design process between artist and researcher

The Serendiptichord is a wearable instrument, resulting from a collaboration crossing fashion, technology, music and dance. This paper reflects on the collaborative process and how defining both creative and research roles for each party led to a successful creative partnership built on mutual respect and open communication. After a brief snapshot of the instrument in performance, the instrument is considered within the context of dance-driven interactive music systems followed by a discussion on the nature of the collaboration and its impact upon the design process and final piece

Learning Policies from Self-Play with Policy Gradients and MCTS Value Estimates

In recent years, state-of-the-art game-playing agents often involve policies that are trained in self-playing processes where Monte Carlo tree search (MCTS) algorithms and trained policies iteratively improve each other. The strongest results have been obtained when policies are trained to mimic the search behaviour of MCTS by minimising a cross-entropy loss. Because MCTS, by design, includes an element of exploration, policies trained in this manner are also likely to exhibit a similar extent of exploration. In this paper, we are interested in learning policies for a project with future goals including the extraction of interpretable strategies, rather than state-of-the-art game-playing performance. For these goals, we argue that such an extent of exploration is undesirable, and we propose a novel objective function for training policies that are not exploratory. We derive a policy gradient expression for maximising this objective function, which can be estimated using MCTS value estimates, rather than MCTS visit counts. We empirically evaluate various properties of resulting policies, in a variety of board games.Comment: Accepted at the IEEE Conference on Games (CoG) 201

Can guidelines improve referral to elective surgical specialties for adults? A systematic review

Aim To assess effectiveness of guidelines for referral for elective surgical assessment. Method Systematic review with descriptive synthesis. Data sources Medline, EMBASE, CINAHL and Cochrane database up to 2008. Hand searches of journals and websites. Selection of studies Studies evaluated guidelines for referral from primary to secondary care, for elective surgical assessment for adults. Outcome measures Appropriateness of referral (usually measured as guideline compliance) including clinical appropriateness, appropriateness of destination and of pre-referral management (eg, diagnostic investigations), general practitioner knowledge of referral appropriateness, referral rates, health outcomes and costs. Results 24 eligible studies (5 randomised control trials, 6 cohort, 13 case series) included guidelines from UK, Europe, Canada and the USA for referral for musculoskeletal, urological, ENT, gynaecology, general surgical and ophthalmological conditions. Interventions varied from complex (“one-stop shops”) to simple guidelines. Four randomized control trials reported increases in appropriateness of pre-referral care (diagnostic investigations and treatment). No evidence was found for effects on practitioner knowledge. Mixed evidence was reported on rates of referral and costs (rates and costs increased, decreased or stayed the same). Two studies reported on health outcomes finding no change. Conclusions Guidelines for elective surgical referral can improve appropriateness of care by improving prereferral investigation and treatment, but there is no strong evidence in favour of other beneficial effects

You Can\u27t Just Pick One Race and You Shouldn\u27t Have To: Analyzing Biracial Protagonists in Young Adult Fiction

In recent years, Children’s Literature has seen a notable increase of texts involving racial diversity. One area that does not garner as much attention is Young Adult fiction with biracial protagonists. With the growing number of families in the United States identifying as biracial or multi-racial, it is important to examine the representations of biracial characters offered to readers. Poston has noted that biracial adolescents often experience crisis and alienation, as they are forced to choose an identity that does not fully encompass their complex racial background (Nuttgens 2010). Sarah Jamila Stevenson’s The Latte Rebellion (2011), Joan Steinau Lester’s Black, White, Other (2011), and Sandra Forrester’s Dust from Old Bones (1999) work against the idea that people should have to choose a racial identity that alienates them from a part of themselves, arguing instead that the world is not divided into stark identity categories, though recognizing racial differences remains of the utmost importance. The characters in these novels are able to navigate the channels of being biracial, while developing a sense of what Lourdes India Ivory calls “biracial competency” and “biracial efficacy,” allowing them to function successfully within both racial groups (Ivory 2010). This research analyzes authorial depictions of biracial characters, and the effect these depictions have on character identity development throughout the novels