Search results for "limited"
showing 10 items of 177 documents
Spectral Structures in Econometrics: Modern Techniques in Wavelet Analysis and Band Limited Estimation
2007
This thesis presents a number of innovative techniques that can be used in the analysis of econometric data sequences in which the underlying components can be identified by their spectral signatures. To present these techniques intelligibly requires the preparatory expositions of Fourier analysis and of the theory of linear filtering that are presented in Chapters 2 and 3. Amongst the techniques for extracting components from short non stationary sequences that are described in Chapter 3 is a variant of the Hodrick--Prescott filter with a smoothing parameter that varies locally. This enables us to extract from the data trends that incorporate a number of structural breaks. The inadequacy o…
Non-Dyadic Wavelet Analysis
2006
The conventional dyadic multiresolution analysis constructs a succession of frequency intervals in the form of $(\pi/2^j, \pi/2^{j-1});j = 1, 2, \ldots, n$ of which the bandwidths are halved repeatedly in the descent from high frequencies to low frequencies. Whereas this scheme provides an excellent framework for encoding and transmitting signals with a high degree of data compression, it is less appropriate to the purposes of statistical data analysis. This paper describes a non-dyadic mixed-radix wavelet analysis which allows the wave bands to be defined more flexibly than in the case of a conventional dyadic analysis. The wavelets that form the basis vectors for the wave bands are derive…
Diagnostic yield of a one sample immunochemical test at different cut-off values in an organised screening programme for colorectal cancer
2013
Abstract Background Quantitative immunochemical faecal occult blood tests have become the recommended tests for colorectal cancer screening. The aim of this study was to complete our knowledge on the performance of one of the quantitative immunochemical tests available, FOB-Gold, and to propose a possible strategy for an organised screening programme. Patients and methods Within the French organised screening programme, 23,231 average-risk individuals, aged 50–74 performed both a 3-day Hemoccult test and a 1-day FOB-Gold test. Performances of the immunochemical test were evaluated at different cut-off levels. Results The positivity rate for the Hemoccult was 2.1% and for the FOB-Gold varied…
Analysis of health communication texts: UK press coverage of debates about assisted dying
2015
Conventionally, social researchers analyse media messages by reading text and coding it. This is time consuming and restricts many studies to small samples. Nowadays very large amounts of text are available in electronic form, offering potential insights into the health messages they contain, but which appear daunting to the analyst with limited resources using conventional methods. I explain and illustrate methods for the computer-assisted analysis of media texts, using specialised software (Wordsmith Tools and Wordstat). These allow the analyst to provide a statistical overview of the key features of texts, to compare them (looking at change over time, for example) and to select illustrat…
Linking Disaster Risk Reduction and Healthcare in Locations with Limited Accessibility: Challenges and Opportunities of Participatory Research
2020
Disaster risk reduction and healthcare support each other, including the mitigation of further harm after illness or injury. These connections are particularly relevant in locations which have permanent or temporary limited accessibility. In these circumstances, people are required to be self-sufficient in providing emergency and long-term healthcare with limited resources. Planning and preparing to mitigate further harm after illness or injury from disasters (disaster risk reduction) must include people living and working in locations with limited accessibility, meaning that participatory research can be used. The challenges and opportunities of enacting participatory research in such cont…
Fronts propagating with signal dependent speed in limited diffusion and related Hamilton-Jacobi formulations
2021
We consider a class of limited diffusion equations and explore the formation of diffusion fronts as the result of a combination of diffusive and hyperbolic transport. We analyze a new class of Hamilton-Jacobi equations arising from the convective part of general Fokker-Planck equations ruled by a non-negative diffusion coefficient that depends on the unknown and on the gradient of the unknown. We explore the main features of the solution of the Hamilton-Jacobi equations that contain shocks and propose a suitable numerical scheme that approximates the solution in a consistent way with respect to the solution of the associated Fokker-Planck equation. We analyze three model problems covering d…
Development, Current Situation and Future Prospects of the Private Sport Sector in Europe
2017
This book outlined the private sport sector of the 18 European countries by using the Statistical classification of economic activities in the European Community (NACE Rev. 2, 2008) as a basic statistical framework. According on the country chapters European sport is divided into public, voluntary and private sectors. Depending on how strongly and through what kind of historical processes these sectors have developed, European countries taking part in this project can be classified as 1) historically and traditionally strong non-profit voluntary sport sector countries, 2) former Eastern Bloc countries and 3) countries with strong commercial sport activities. Based on the statistics, sport g…
Determinants of COVID-19 Vaccine Rollouts and Their Effects on Health Outcomes
2022
Background Vaccination against the coronavirus disease (SARS-CoV-2) is understood to be the key way out of the COVID-19 pandemic. Limited evidence exists on the determinants of vaccine rollouts and their health effects at the country level. Objective Examine the determinants of COVID-19 vaccine rollouts and their effects on health outcomes. Methods Ordinary least squares regressions with standard errors clustered at the country level for Cross-section and Panel daily data of vaccinations and various health outcomes (new COVID-19 cases, fatalities, intensive care unit (ICU) admissions) for an unbalanced sample of about 200 countries during the period 16 December 2020 to 20 June 2021. Results…
Unawareness and Partitional Information Structures
1999
Abstract We claim first that simple uncertainty is not an adequate model of a subject's ignorance, because a major component of it is the inability to give a complete description of the states of the world, and we provide a formal model of unawareness. In Modica and Rustichini (1994) we showed a difficulty in the project, namely that without weakening of the inference rules of the logic one would face the unpleasant alternative between full awareness and full unawareness. In this paper we study a logical system where non full awareness is possible, and prove that a satisfactory solution to the problem can be found by introducing limited reasoning ability of the subject. A determination theo…
Impedance of space-charge-limited currents in organic light-emitting diodes with double injection and strong recombination
2006
The impedance model for a one-carrier space-charge-limited (SCL) current has been applied to explain some experimental features of double carrier organic light-emitting diodes. We report the analytical model of impedance of bipolar drift transport in SCL regime in the limit of infinite recombination. In this limit the ac impedance function is identical to that of a single carrier device, with a transit time modified by the sum of mobilities for electrons and holes, μn+μp. The static capacitance C(ω→0) is a factor of ¾ lower than the geometric capacitance, as observed for single carrier devices, but it is shifted to higher frequencies. It follows that impedance measurements in the dual-carri…