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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Market perceptions of efficiency and news in analyst forecast errors

Chevis, Gia Marie 15 November 2004 (has links)
Financial analysts are considered inefficient when they do not fully incorporate relevant information into their forecasts. In this dissertation, I investigate differences in the observable efficiency of analysts' earnings forecasts between firms that consistently meet or exceed analysts' earnings expectations and those that do not. I then analyze the extent to which the market incorporates this (in)efficiency into its earnings expectations. Consistent with my hypotheses, I find that analysts are relatively less efficient with respect to prior returns for firms that do not consistently meet expectations than for firms that do follow such a strategy, especially when prior returns convey bad news. However, forecast errors for firms that consistently meet expectations do not appear to be serially correlated to a greater extent than those for firms that do not consistently meet expectations. It is not clear whether the market considers such inefficiency when setting its own expectations. While the evidence suggests they may do so in the context of a shorter historical pattern of realized forecast errors, other evidence suggests they may not distinguish between predictable and surprise components of forecast error when the historical forecast error pattern is more established.
112

Stochastic modeling of the variation of velocity and permeability as a function of effective pressure using the Bed-of-Nails asperity-deformation model

Genova Barazarte, Ezequiel 15 May 2009 (has links)
The mechanical and transport properties of porous and cracked media, such as velocity and permeability, are sensitive to the effects of effective pressure, which itself is a function of the confining pressure and the pore-fluid pressure. The dependence of permeability and velocity on effective pressure has previously been modeled using the Bed-of-Nails asperity-deformation model. The main objective of this research was to explore the sensitivity of the Bed-of-Nails and effective-pressure models to random, Gaussian errors, by using an inverse approach. To achieve this, numerical modeling of pre-existing velocity and permeability experimental data sets was done. Extrapolation to 600 MPa was performed using an epidosite data set of compressional velocity as a function of confining pressure, only using measurements in the range 0-100 MPa. The results showed that, given sufficient data and considering random error only, extrapolation can be done with a level of error of less than 1.5%. Model error can also be significant in this type of exercise because it can give rise to systematic misfit, although in this case it was shown that the effects of model error were not considerable. Modeling the variation of compressional velocities as a function of confining and pore-fluid pressures in a deep-sea chalk showed that the best-fitting asperity-deformation model is sensitive to the effective-pressure model. Measurements of permeability in a Navajo-sandstone specimen as a function of confining pressure were numerically modeled, and the results showed that measurements made at low pressures, specifically near Pe = 0, are very important to constrain the model. The same result was found in the case of permeability as a function of confining and pore-fluid pressure in a Wilcox-shale where the lack of measurements near Pe = 0 caused the error in the model parameters to be overestimated. This occurs because the rate of change of permeability as a function of effective pressure is very high at low pressures. The lack of sufficient data near Pe = 0 overestimates the curvature matrix and, therefore, the errors in the model parameters.
113

Hedging errors of discrete hedge: the comparison of BS model and Merton model

Lin, Chia-Lou 13 July 2001 (has links)
none
114

Market perceptions of efficiency and news in analyst forecast errors

Chevis, Gia Marie 15 November 2004 (has links)
Financial analysts are considered inefficient when they do not fully incorporate relevant information into their forecasts. In this dissertation, I investigate differences in the observable efficiency of analysts' earnings forecasts between firms that consistently meet or exceed analysts' earnings expectations and those that do not. I then analyze the extent to which the market incorporates this (in)efficiency into its earnings expectations. Consistent with my hypotheses, I find that analysts are relatively less efficient with respect to prior returns for firms that do not consistently meet expectations than for firms that do follow such a strategy, especially when prior returns convey bad news. However, forecast errors for firms that consistently meet expectations do not appear to be serially correlated to a greater extent than those for firms that do not consistently meet expectations. It is not clear whether the market considers such inefficiency when setting its own expectations. While the evidence suggests they may do so in the context of a shorter historical pattern of realized forecast errors, other evidence suggests they may not distinguish between predictable and surprise components of forecast error when the historical forecast error pattern is more established.
115

Tracking-history-based Sleeping Policies for Wireless Sensor Networks

Gau, Ding-hau 29 July 2009 (has links)
A wireless sensor network can be used to track an object. Every sensor has limited energy and detecting range. In order to conserve energy, sensors may be put into sleeping mode. A sensor in the sleeping mode can not communicate with other sensors or detect objects. When the object moves to the sensing range of a sleeping sensor, a tracking error occurs. To minimize the tracking error subject to an constraint on energy consumption, we should determine the sleeping schedules of sensors based on the mobility pattern of the object. We propose determining the sleeping schedules based on the observation history of the moving object. We use computer simulation to justify the usage of the proposed approach.
116

Grammar and cognitive processing of news articles exploring dual-processing theories /

Appelman, Alyssa. Bolls, Paul David, January 2009 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 17, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Paul Bolls. Includes bibliographical references.
117

Methodology for evaluating and reducing medication administration errors

Boone, Amanda Carrie. January 2003 (has links)
Thesis (M.S.)--Mississippi State University. Department of Industrial Engineering. / Title from title screen. Includes bibliographical references.
118

The prevalence of refractive error and visual impairment caused by uncorrected refractive error in China

Ng, Siu-chun, Danny., 吳兆駿. January 2010 (has links)
Purpose: WHO reports 46% of world vision impairment from refractive error (RE) among children occurs in China. We estimated RE prevalence and associated vision impairment (VI) among Chinese children and adults. Methods: Data from population-based studies were stratified by gender in age intervals of 3 years (ages 3-17 y) or 10 years (ages >= 30 y): counts of persons with myopia (worse eye spherical equivalent <= -1.0D, <= -2.0D, <= -6.0D) and prevalence of low vision (< 6/12 in the better-seeing eye for children and < 6/18 for adults) and blindness (<=6/60) attributable to RE. Figures for VI included persons with habitual vision below the cutoff improving to above the cutoff with refraction, and those with myopic retinopathy. Estimates for ages 18-29 y were obtained from regression models derived from the pooled estimates. Prevalence of myopia and VI attributable to RE in each age/gender category was calculated by applying modeled rates to 2000 China census figures and projections for 2020. Association with VI attributable to RE was tested for: gender, urban versus rural residence, and residence in provinces with per capita GDP in the upper versus lower 50% for China. Results: Data were obtained from 5 cohorts for children and 14 for adults. There were 291 million and 21.4 million persons with myopia <= -1.0D and <= -6.0D respectively in 2000, expected to rise to 306 million and 36.9 million by 2020. Of these, 18.4 million were blind and 116 million had low vision in 2000, with figures of 25.3 million and 123 million in 2020. Children accounted for the following proportion of RE disease burden in China in 2000: myopia <= -1.0D: 19.0%; RE-associated low vision: 56.1%; blindness: 14.1%. Refractive error was responsible for 82.3% of blindness and 90.5% of low vision among children, and 11.6% and 64.4% of blindness and low vision among adults. Urban residence (OR 1.85, P = 0.004) and higher GDP (OR 10.6, P < 0.001) were associated with refractive blindness among children. For adults, lower GDP was associated with refractive blindness (OR 1.47, P = 0.01). Gender was un-associated with refractive blindness among children or adults. Conclusions: Both children and adults suffer a heavy burden of VI associated with RE in China. Income may affect risk for such VI differently among children and adults. / published_or_final_version / Public Health / Master / Master of Public Health
119

Chemical pathology analysis of inborn errors of metabolism for expanded newborn screening in Hong Kong

Mak, Miu., 麥苗. January 2012 (has links)
Inborn errors of metabolism (IEM) are under international spotlight because of the recent tremendous development in expanded newborn screening (NBS) and molecular genetics. IEM is a difficult subject involving more than 1,000 different disorders with protean clinical presentations and complicated diagnostic pathways. Cumulative incidence of IEM was reported up to 1 in 800. Patients can be affected in any ages. High clinical suspicion alone is not sufficient to reduce morbidities and mortalities. Notably, some IEM are amenable to treatment with promising outcome. Local data regarding the disease spectrum and incidences is largely lacking. Public awareness and readiness for expanded NBS is unknown. This renders difficulties in the consideration of expanded NBS in Hong Kong. In this study, laboratory data of classical IEM from 2005 to 2009 were retrospectively analyzed (Chapter 2). Local incidence was 1 in 4,122 and that of hyperphenylalaninemias was 1 in 29,542, similar to worldwide figures. Majority (69%) was amino acid disorders, 12% was organic acidemias and 19% was fatty acid oxidation defects. Most of these diseases are effectively amenable to treatment. Local cases including hyperphenylalaninemia, tyrosinemia type I, arginase deficiency, ornithine transcarbamylase deficiency, very long-chain acyl-CoA dehydrogenase deficiency, tyrosine hydroxylase deficiency, thermolabile carnitine palmitoyltransferase II variants and adults IEM with X-linked adrenoleukodystrophy, cerebrotendinous xanthomatosis, familial transthyretin amyloidosis, Wilson disease and PANK2-associated young-onset Parkinsonism were described (Chapters 1.1.3 and 3). Electronic chemical pathology consultation service and dried blood spot metabolic screening were implemented (Chapter 4). There were 279 consultations and 158 screening in a 12-month period. Major referral reasons were developmental delay, neurological defects and unexplained biochemical abnormalities. The incidence in high risk screening was 1 in 158. A non-derivatized tandem mass spectrometry assay for amino acids and acylcarnitines was evaluated for its precision, accuracy and reference intervals (Chapter 5). The concordance rate was 100% in inter-laboratory comparison and external quality assurance programs. The method was proven to be accurate, rapid and affordable. It is suitable for large volume testing and emergency diagnostic needs. A feasibility study of a hospital-based expanded NBS service model was conducted on 360 newborns (Chapter 6). More than 90% of babies were older than 48 hours before discharge and were fit for blood collection. The service model consisted of parent education, consent, postnatal sample collection, technical analysis, clinical interpretation, reporting and follow-up actions. Questionnaire on the knowledge and attitude towards IEM and expanded NBS was surveyed on 172 parents to investigate the psychological, social and ethical aspects (Chapter 7). Here, 99.4% demanded more education on expanded NBS; 97.6% supported to implement the program; 97.7% supported population screening even though some diseases are incurable. Availability of treatment is not the most important pre-requisite for NBS; 93.9% accepted the possibility of false positive and false negative results. Acceptance towards expanded NBS among parents was high. Our data indicate that IEM is not uncommon in Hong Kong and it is indisputable for the introduction of a local expanded NBS program. Our data serve as groundwork for policy decision and further discussion on expanded NBS. / published_or_final_version / Pathology / Master / Doctor of Medicine
120

Signal Emitter Localization Using Telemetry Assets

Parker, Peter A., Lake, Melina 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Telemetry ground stations spread over geographically diverse areas are well suited for use in passively locating the source of a distant transmitted signal. In a favorable positioning of receive sites, the accuracy of these passive localization techniques can compete with the accuracy of radars. In these cases, use of receive only assets is a less expensive alternative than the use of a radar's scarce resources. Until recently, the major technical challenge to implementation of the passive localization techniques of time-difference of arrival (TDOA) and frequency-difference of arrival (FDOA) has been the frequency and time stability of geographically separated receivers. Advances in GPS based timing and frequency references has made the implementation of TDOA and FDOA feasible. This paper shows how these limitations have been overcome using the current telemetry assets at the Reagan Test Site in Kwajalein Atoll.

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