The Return To Tax Simplification: an Econometric Analysis

This article provides estimates of the probable saving in the resource cost of complying with the tax law that would result from simplifying the individual Abstract income tax law. These estimates are based on an econometric analysis of the tax-filing behavior in 1982 of a sample of Minnesota taxpayers. A simple model of tax-compliance behavior based on utility maximization is first presented in order to suggest the important determinants of compliance behavior. The empirical model treats the discrete choices of whether to itemize deductions and whether to hire professional tax advice, and the choice of how much time and money to spend, conditional on the discrete choices made. Simulations based on the econometric results suggest that significant resource saving could be expected from eliminating the system of itemized deductions, although no significant saving from changing to a single-rate tax structure can be confidently predicted. Results suggest that the Tax Reform Act of 1986 will, in the long run, decrease the use ofprofessional tax assistance, but its net effect on the use of taxpayer's own time is unclear.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68711/2/10.1177_109114218901700101.pd

Critical exponents of directed percolation measured in spatiotemporal intermittency

A new experimental system showing a transition to spatiotemporal intermittency is presented. It consists of a ring of hundred oscillating ferrofluidic spikes. Four of five of the measured critical exponents of the system agree with those obtained from a theoretical model of directed percolation.Comment: 7 pages, 12 figures, submitted to PR

The UKIDSS Galactic Plane Survey

'The definitive version is available at www.blackwell-synergy.com .' Copyright Blackwell Publishing DOI: 10.1111/j.1365-2966.2008.13924.xThe UKIDSS Galactic Plane Survey (GPS) is one of the five near-infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared TelescopePeer reviewe

Experimental and computational studies of sonochemical assisted anchoring of carbon quantum dots on reduced graphene oxide sheets towards the photocatalytic activity

Herein, carbon quantum dots (CQDs) are anchored on reduced graphene oxide (rGO) sheets by sonochemical assisted method. The developed carbon quantum dots/reduced graphene oxide (CQDs/rGO) catalyst shows enhancement in the photocatalytic degradation of methylene blue and methyl orange under visible light compared to that of individual CQDs and rGO components. The improved performance of the CQDs/rGO catalyst has been attributed to efficient separation of photogenerated charge carriers as studied by photoluminescence studies and to increase in the surface area as studied by Brunauer-Emmett-Teller method. The photocatalytic degradation is studied in detail by varying catalyst loading, dye concentration and the rate constant is determined by first order kinetics. The enhancement in photocatalytic activity of CQDs/rGO catalyst is validated by first principles density functional theory (DFT) calculations which shows the enrichment in density of states thereby decreasing the work function

Accuracy of the no-biopsy approach for the diagnosis of coeliac disease in adults: a systematic review and meta-analysis

BACKGROUND & AIMS: Current international guidelines recommend duodenal biopsies to confirm the diagnosis of coeliac disease in adult patients. However, growing evidence suggests that IgA anti-tissue transglutaminase (tTg) antibody levels ≥10 times the upper limit of normal (ULN) can accurately predict coeliac disease, eliminating the need for biopsy. We performed a systematic review and meta-analysis to evaluate the accuracy of the no-biopsy approach to confirm the diagnosis of coeliac disease in adults. METHODS: We systematically searched MEDLINE, EMBASE, Cochrane Library and Web of Science from January 1998 to October 2023 for studies reporting the sensitivity and specificity of IgA-tTG ≥10×ULN against duodenal biopsies (Marsh grade ≥2) in adults with suspected coeliac disease. We used a bivariate random-effects model to calculate the summary estimates of sensitivity, specificity, positive and negative likelihood ratios. The positive and negative likelihood ratios were used to calculate the positive predictive value (PPV) of the no-biopsy approach across different pre-test probabilities of coeliac disease. The methodological quality of the included studies was evaluated using the QUADAS-2 tool. This study was registered with PROSPERO, number CRD42023398812. RESULTS: A total of 18 studies comprising 12,103 participants from 15 countries were included. The pooled prevalence of biopsy-proven coeliac disease in the included studies was 62% (95% CI, 40% - 83%). The proportion of patients with IgA-tTG ≥10×ULN was 32% (95% CI, 24% - 40%). The summary sensitivity of IgA-tTG ≥10×ULN was 51% (95% CI, 42% - 60%), and the summary specificity was 100% (95% CI, 98% - 100%). The area under the summary receiver operating characteristic curve was 0.83 (95% CI, 0.77 - 0.89). The PPV of the no-biopsy approach to identify patients with coeliac disease was 65%, 88%, 95%, and 99% if coeliac disease prevalence was 1%, 4%, 10% and 40%, respectively. Between-study heterogeneity was moderate (I2 =30.3%), and additional sensitivity analyses did not significantly alter our findings. Only one study had a low risk of bias across all domains. CONCLUSION: The results of this meta-analysis suggest that selected adult patients with IgA-tTG ≥10×ULN and a moderate to high pre-test probability of coeliac disease could be diagnosed without undergoing invasive endoscopy and duodenal biopsy

Spinor condensates and light scattering from Bose-Einstein condensates

These notes discuss two aspects of the physics of atomic Bose-Einstein condensates: optical properties and spinor condensates. The first topic includes light scattering experiments which probe the excitations of a condensate in both the free-particle and phonon regime. At higher light intensity, a new form of superradiance and phase-coherent matter wave amplification were observed. We also discuss properties of spinor condensates and describe studies of ground--state spin domain structures and dynamical studies which revealed metastable excited states and quantum tunneling.Comment: 58 pages, 33 figures, to appear in Proceedings of Les Houches 1999 Summer School, Session LXXI

On universality of critical behavior in the focusing nonlinear Schr\uf6dinger equation, elliptic umbilic catastrophe and the Tritronqu\ue9e solution to the Painlev\ue9-I equation

We argue that the critical behavior near the point of "gradient catastrophe" of the solution to the Cauchy problem for the focusing nonlinear Schrodinger equation i epsilon Psi(t) + epsilon(2)/2 Psi(xx) + vertical bar Psi vertical bar(2)Psi = 0, epsilon << 1, with analytic initial data of the form Psi( x, 0; epsilon) = A(x)e(i/epsilon) (S(x)) is approximately described by a particular solution to the Painleve-I equation

Glastir Monitoring & Evaluation Programme. Second year annual report

What is the purpose of Glastir Monitoring and Evaluation Programme? Glastir is the main scheme by which the Welsh Government pays for environmental goods and services whilst the Glastir Monitoring and Evaluation Programme (GMEP) evaluates the scheme’s success. Commissioning of the monitoring programme in parallel with the launch of the Glastir scheme provides fast feedback and means payments can be modified to increase effectiveness. The Glastir scheme is jointly funded by the Welsh Government (through the Rural Development Plan) and the EU. GMEP will also support a wide range of other national and international reporting requirements. What is the GMEP approach? GMEP collects evidence for the 6 intended outcomes from the Glastir scheme which are focussed on climate change, water and soil quality, biodiversity, landscape, access and historic environment, woodland creation and management. Activities include; a national rolling monitoring programme of 1km squares; new analysis of long term data from other schemes combining with GMEP data where possible; modelling to estimate future outcomes so that adjustments can be made to maximise impact of payments; surveys to assess wider socio-economic benefits; and development of novel technologies to increase detection and efficiency of future assessments. How has GMEP progressed in this 2nd year? 90 GMEP squares were surveyed in Year 2 to add to the 60 completed in Year 1 resulting in 50% of the 300 GMEP survey squares now being completed. Squares will be revisited on a 4 year cycle providing evidence of change in response to Glastir and other pressures such as changing economics of the farm business, climate change and air pollution. This first survey cycle collects the baseline against which future changes will be assessed. This is important as GMEP work this year has demonstrated land coming into the scheme is different in some respects to land outside the scheme. Therefore, future analysis to detect impact of Glastir will be made both against the national backdrop from land outside the scheme and this baseline data from land in scheme. A wide range of analyses of longterm data has been completed for all Glastir Outcomes with the exception of landscape quality and historic features condition for which limited data is available. This has involved combining data with 2013/14 GMEP data when methods allow. Overall analysis of long term data indicates one of stability but with little evidence of improvement with the exception of headwater quality, greenhouse gas emissions and woodland area for which there has been improvement over the last 20 years. Some headline statistics include: 51% of historic features in excellent or sound condition; two thirds of public rights of way fully open and accessible; improvement in hedgerow management with 85% surveyed cut in the last 3 years but < 1% recently planted; 91% of streams had some level of modification but 60% retained good ecological quality; no change topsoil carbon content over last 25 years. What is innovative? GMEP has developed various new metrics to allow for more streamlined reporting in the future. For example a new Priority Bird species Index for Wales which combines data from 35 species indicates at least half have stable or increasing populations. The new GMEP Visual Quality Landscape Index has been tested involving over 2600 respondents. Results have demonstrated its value as an objective and repeatable method for quantifying change in visual landscape quality. A new unified peat map for Wales has been developed which has been passed to Glastir Contract Managers to improve targeting of payments when negotiating Glastir contracts. An estimate of peat soil contribution to current greenhouse gas emissions due to human modification has been calculated. Models have allowed quantification of land area helping to mitigate rainfall runoff. We are using new molecular tools to explore the effects of Glastir on soil organisms and satellite technologies to quantify e.g. small woody features and landcover change. Finally we are using a community approach to develop a consensus on how to define and report change in High Nature Value Farmland which will be reported in the Year 3 GMEP report

A review of spatial causal inference methods for environmental and epidemiological applications

The scientific rigor and computational methods of causal inference have had great impacts on many disciplines, but have only recently begun to take hold in spatial applications. Spatial casual inference poses analytic challenges due to complex correlation structures and interference between the treatment at one location and the outcomes at others. In this paper, we review the current literature on spatial causal inference and identify areas of future work. We first discuss methods that exploit spatial structure to account for unmeasured confounding variables. We then discuss causal analysis in the presence of spatial interference including several common assumptions used to reduce the complexity of the interference patterns under consideration. These methods are extended to the spatiotemporal case where we compare and contrast the potential outcomes framework with Granger causality, and to geostatistical analyses involving spatial random fields of treatments and responses. The methods are introduced in the context of observational environmental and epidemiological studies, and are compared using both a simulation study and analysis of the effect of ambient air pollution on COVID-19 mortality rate. Code to implement many of the methods using the popular Bayesian software OpenBUGS is provided