Post-selection point and interval estimation of signal sizes in Gaussian samples

We tackle the problem of the estimation of a vector of means from a single vector-valued observation $y$. Whereas previous work reduces the size of the estimates for the largest (absolute) sample elements via shrinkage (like James-Stein) or biases estimated via empirical Bayes methodology, we take a novel approach. We adapt recent developments by Lee et al (2013) in post selection inference for the Lasso to the orthogonal setting, where sample elements have different underlying signal sizes. This is exactly the setup encountered when estimating many means. It is shown that other selection procedures, like selecting the $K$ largest (absolute) sample elements and the Benjamini-Hochberg procedure, can be cast into their framework, allowing us to leverage their results. Point and interval estimates for signal sizes are proposed. These seem to perform quite well against competitors, both recent and more tenured. Furthermore, we prove an upper bound to the worst case risk of our estimator, when combined with the Benjamini-Hochberg procedure, and show that it is within a constant multiple of the minimax risk over a rich set of parameter spaces meant to evoke sparsity.Comment: 27 pages, 13 figure

Quadratic Neural Network Architecture as Evaluated Relative to Conventional Neural Network Architecture

Current work in the field of deep learning and neural networks revolves around several variations of the same mathematical model for associative learning. These variations, while significant and exceptionally applicable in the real world, fail to push the limits of modern computational prowess. This research does just that: by leveraging high order tensors in place of 2nd order tensors, quadratic neural networks can be developed and can allow for substantially more complex machine learning models which allow for self-interactions of collected and analyzed data. This research shows the theorization and development of mathematical model necessary for such an idea to work appropriately in an analogous fashion to current models, and then explores through Monte-Carlo simulations the industry-standard measures of fit of such a model

A Study of the Determinants of Transfer Fees For French Ligue 1 Soccer Players

In light of the increasing flow of millions of dollars into the sports industry during the last two decades, notably the international soccer market, the repercussions from the wave of economic activity have come under scrutiny by economists. In France alone, while the real Gross Domestic Product for the country has grown at an annualized rate of 2.75%, the soccer industry in France has experienced a 500% growth in ticket sales, 3,300% growth in sponsorship income, 122,000% increase in income from television contracts overall during the same time period (Bourg and Gouget, 2005). Sports have become such a pivotal facet of the economic structure due to their status as an integral part of today’s society with upwards of 20% of French citizens partaking in licensed athletic events and 75% claiming to be participants in sporting activities, both professional and recreational. It has been increasingly evident that the actions taken by professional sports teams have a far reaching impact on the global market

A sensory-guided surgical micro-drill

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 The Authors.This article describes a surgical robotic device that is able to discriminate tissue interfaces and other controlling parameters ahead of the drill tip. The advantage in such a surgery is that the tissues at the interfaces can be preserved. A smart tool detects ahead of the tool point and is able to control the interaction with respect to the flexing tissue, to avoid penetration or to control the extent of protrusion with respect to the position of the tissue. For surgical procedures, where precision is required, the tool offers significant benefit. To interpret the drilling conditions and the conditions leading up to breakthrough at a tissue interface, a sensing scheme is used that discriminates between the variety of conditions posed in the drilling environment. The result is a fully autonomous system, which is able to respond to the tissue type, behaviour, and deflection in real-time. The system is also robust in terms of disturbances encountered in the operating theatre. The device is pragmatic. It is intuitive to use, efficient to set up, and uses standard drill bits. The micro-drill, which has been used to prepare cochleostomies in the theatre, was used to remove the bone tissue leaving the endosteal membrane intact. This has enabled the preservation of sterility and the drilling debris to be removed prior to the insertion of the electrode. It is expected that this technique will promote the preservation of hearing and reduce the possibility of complications. The article describes the device (including simulated drill progress and hardware set-up) and the stages leading up to its use in the theatre.Queen Elizabeth Hospital, Birmingham, U

Solar neutrino physics at dark matter direct detection experiments

As the sensitivity of direct detection experiments improves, they will soon be subject to a new, irreducible background from the coherent elastic scattering of solar neutrinos with nuclei. The presence of new physics can modify this scattering rate, and signals of neutrino scattering may appear in direct detection experiments sooner than expected. In this thesis, we explore the effects of several simplified models of new physics on neutrino scattering at direct detection experiments. We introduce the neutrino contour, a projection of the modified coherent neutrino scattering rate on a dark matter parameter space. This contour can be used to quickly identify whether a direct detection experiment could set competitive constraints on a given model, or conversely, whether the model could produce a large enough neutrino scattering rate to hinder searches for dark matter at that experiment. We discuss the subtleties that arise while computing constraints from the results of one experiment, CDMSlite, in particular the challenges of including electron scattering in the analysis. Finally, we calculate the sensitivity of several future direct detection experiments to one model, the \umt. We find that the upcoming LUX-ZEPLIN experiment will be able to test solutions to two ongoing problems in fundamental physics: the muon g-2 anomaly and the $H_0$ tension

A Comparative Study of the Effects of Microalgae on Poultry Production

Research has shown Spirulina to be a viable feedstuff in poultry production. Other species of microalgae are being studied to determine their effects on poultry production. This project compared four microalgaes: Hydrodictyon, Vaucheria, Uronema, and Spirulina and was broken down into three trials. The first experiment investigated the digestibility of an algae species, Spirulina, in broiler chicken diets. Eighty, 25-day-old Ross 708 broiler chicks were sorted into 20 metabolism cages and received one of two diets: Control Diet or Test Diet (75% basal diet + 25% Spirulina). The apparent ileal amino acid digestibility (AIAAD) of lysine, methionine, cysteine, threonine, isoleucine, valine and arginine in Spirulina was 94.5%, 91.3%, 56.1%, 71.4%, 76.8%, 69.8% and 90.4% respectively. Apparent metabolizable energy (AME) of Spirulina was 2279 kcal/kg. The second experiment focused on digestibility of Spirulina and novel algae species in laying hens. Sixty, 80-week-old Lohman LSL-Lite laying hens were randomly assigned to Control Diet, Hydrodictyon Test Diet (87.5% basal diet + 12.5% hydrodictyon), 12.5% or one of three other test diets (75% basal diet + 25% Spirulina, Uronema, and Vaucheria). Spirulina diets contained the highest crude protein (25.5%) and methionine levels (0.68%). Uronema had the highest gross energy content of 3880.5 kcal/kg and lysine levels (1.12%). Hydrodictyon diet was the most nutritionally similar to the control. Crude protein was at 15.3% and 16.6% for control and Hydrodictyon respectively. Gross energy was 3429.6 kcal/g in control versus 3316.1 kcal/kg in Hydrodictyon. Lastly, crude fat was 2.7% compared to Hydrodictyon at 2.4%. The last trial was to determine the effects of the addition of microalgae in the diet on laying hen production. Seventy-eight, 23-month-old laying hens were assigned to 1 of 3 of the following experimental diets: control, control + 1% microalgae, or control + 2% microalgae. Microalgae, regardless of inclusion level, had no significant effect on egg weight in this study. Increasing level of inclusion of Spirulina, Hydrodictyon, and Uronema from 0 to 2 % significantly increased yolk color. Vaucheria influenced yolk color at the 2% level. No significance differences shown from any of the algae species regardless of inclusion level for egg weight, egg mass, shell thickness, shell strength, shell weight, albumen weight, yolk weight, and albumen height. In addition, there was no significant difference in feed conversion ratio, feed intake, body weight, or tibial strength between the treatments. However, as these are novel algaes, further studies are required to determine the true usability in poultry production

Growth and optical characterisation of multilayers of InGaN quantum dots

We report on the growth (using metal-organic vapour phase epitaxy) and optical characterization of single and multiple layers of InGaN quantum dots (QDs), which were formed by annealing InGaN epilayers at the growth temperature in nitrogen. The size and density of the nanostructures have been found to be fairly similar for uncapped single and three layer QD samples if the GaN barriers between the dot layers are grown at the same temperature as the InGaN epilayer. The distribution of nanostructure heights of the final QD layer of three is wider and is centred around a larger size if the GaN barriers are grown at two temperatures (first a thin layer at the dot growth temperature, then a thicker layer at a higher temperature). Micro-photoluminescence studies at 4.2 K of capped samples have confirmed the QD nature of the capped nanostructures by the observation of sharp emission peaks with full width at half maximum limited by the resolution of the spectrometer. We have also observed much more QD emission per unit area in a sample with three QD layers, than in a sample with a single QD layer, as expected

Vaginal Microbiota and the Use of Probiotics

The human vagina is inhabited by a range of microbes from a pool of over 50 species. Lactobacilli are the most common, particularly in healthy women. The microbiota can change composition rapidly, for reasons that are not fully clear. This can lead to infection or to a state in which organisms with pathogenic potential coexist with other commensals. The most common urogenital infection in premenopausal women is bacterial vaginosis (BV), a condition characterized by a depletion of lactobacilli population and the presence of Gram-negative anaerobes, or in some cases Gram-positive cocci, and aerobic pathogens. Treatment of BV traditionally involves the antibiotics metronidazole or clindamycin, however, the recurrence rate remains high, and this treatment is not designed to restore the lactobacilli. In vitro studies have shown that Lactobacillus strains can disrupt BV and yeast biofilms and inhibit the growth of urogenital pathogens. The use of probiotics to populate the vagina and prevent or treat infection has been considered for some time, but only quite recently have data emerged to show efficacy, including supplementation of antimicrobial treatment to improve cure rates and prevent recurrences

Business as Usual: Business Students\u27 Conceptions of Ethics

There is continuing debate about how best to teach ethics to students in business, that is, how best to help them to develop the ethical aspects of their future profession. This debate has covered whether to teach ethics, what to teach and whether it has any effect on students\u27 views or future behaviour. For the most part, the views of the students themselves are in the minority. Yet it seems likely that the most effective pedagogical approaches would be those based on students’ own ideas of the nature of ethics and the role of ethical considerations in their studies and professional lives. The research we report here investigates the nature of such ideas in a cohort of students studying business at an Australian university. We discuss the pedagogical implications of our findings and conclude that approaches that encourage students to become ethically-aware professionals are likely to be most useful