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Similar Methodology (similar + methodology)
Selected AbstractsManaging Risks in Multiple Online Auctions: An Options Approach,DECISION SCIENCES, Issue 3 2005Ram Gopal ABSTRACT The scenario of established business sellers utilizing online auction markets to reach consumers and sell new products is becoming increasingly common. We propose a class of risk management tools, loosely based on the concept of financial options that can be employed by such sellers. While conceptually similar to options in financial markets, we empirically demonstrate that option instruments within auction markets cannot be developed employing similar methodologies, because the fundamental tenets of extant option pricing models do not hold within online auction markets. We provide a framework to analyze the value proposition of options to potential sellers, option-holder behavior implications on auction processes, and seller strategies to write and price options that maximize potential revenues. We then develop an approach that enables a seller to assess the demand for options under different option price and volume scenarios. We compare option prices derived from our approach with those derived from the Black-Scholes model (Black & Scholes, 1973) and discuss the implications of the price differences. Experiments based on actual auction data suggest that options can provide significant benefits under a variety of option-holder behavioral patterns. [source] Rates and social patterning of household smoking and breastfeeding in contrasting European settingsCHILD: CARE, HEALTH AND DEVELOPMENT, Issue 5 2005G. Papadimitriou Abstract Objective To compare rates and social patterning of household smoking and breastfeeding in families with newborn infants in birth cohorts in Coventry, UK and Veria, North Greece. Methods Infants born in 1996 in Coventry, 1999 in Veria were recruited into birth cohort studies using similar methodologies. In Coventry recruitment was by family health visitor at the primary visit; in Veria, hospital-based paediatricians enrolled infants at the neonatal examination. Data were collected at the initial contact on household smoking, type of feeding, and household socio-demographic characteristics. Rates of initial breastfeeding and household smoking with 95% confidence intervals were estimated and breastfeeding and household smoking regressed on parental education and housing tenure in logistic regression models. Results Data were available on 2612 Coventry infants and 773 Veria infants. Rates of household smoking and breastfeeding were higher in Veria compared to Coventry. In Coventry, living in rented accommodation and lower maternal and paternal education were associated with household smoking and bottle feeding. Logistic regression models fitted on initiation of breastfeeding failed to show social patterning in Veria but more educated mothers showed a longer duration of breastfeeding. Only low paternal education was associated with household smoking after adjustment for maternal education and housing tenure. Conclusions Smoking and breastfeeding are more prevalent among households with young infants in Veria compared with Coventry. The social patterning of health-related behaviours noted in Coventry is less marked in Veria. The relevance of these findings for public health interventions in the contrasting settings is discussed. [source] Defining the OE hearg: a preliminary archaeological and topographic examination of hearg place names and their hinterlandsEARLY MEDIEVAL EUROPE, Issue 4 2007Sarah Semple The OE term hearg is interpreted variously as ,pagan temple', ,hilltop sanctuary' and even ,idol'. It is a rare survival in the English place-name record. When it can be identified, the place name is commonly considered to refer to a location of pre-Christian religious activity, specifically a pagan Anglo-Saxon temple. Taking inspiration from the extensive and methodologically well-advanced studies in Scandinavia, which have successfully related place-name evidence for cultic and religious sites with the archaeology and topography of these localities, this paper adopts and uses a similar methodology to investigate the archaeological and topographic character of a selection of hearg locations. The traditional interpretations of the place name are questioned and evidence is presented that these sites are characterized by long-lived, localized cult practice spanning the late prehistoric to early historic periods, but with activity reaching a zenith in the late Iron Age to Romano-British eras, rather than the fifth to seventh centuries AD. [source] Altered knee kinematics in ACL-deficient non-copers: A comparison using dynamic MRIJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2006Peter J. Barrance Abstract Kinematics measured during a short arc quadriceps knee extension exercise were compared in the knees of functionally unstable ACL-deficient patients, these patients' uninjured knees, and uninjured control subjects' knees. Cine phase contrast dynamic magnetic resonance imaging, in combination with a model-based tracking algorithm developed by the authors, was used to measure tibiofemoral kinematics as the subjects performed the active, supine posture knee extension exercise in the terminal 30 degrees of motion. Two determinants of tibiofemoral motion were measured: anterior/posterior location of the tibia relative to the femur, and axial rotation of the tibia relative to the femur. We hypothesized that more anterior tibial positioning, as well as differences in axial tibial rotation patterns, would be observed in ACL-deficient (ACL-D) knees when compared to uninjured knees. Multifactor ANOVA analyses were used to determine the dependence of the kinematic variables on (i) side (injured vs. uninjured, matched by subject in the control group), (ii) flexion angle measured at five-degree increments, and (iii) subject group (ACL-injured vs. control). Statistically significant anterior translation and external tibial rotation (screw home motion) accompanying knee extension were found. The ACL-D knees of the injured group exhibited significantly more anterior tibial positioning than the uninjured knees of these subjects (average difference over extension range,=,3.4,±,2.8 mm, p,<,0.01 at all angles compared), as well as the matched knees of the control subjects. There was a significant effect of interaction between side and subject group on A/P tibial position. We did not find significant differences in external tibial rotation associated with ACL deficiency. The changes to active joint kinematics documented in this entirely noninvasive study may contribute to cartilage degradation in ACL-D knees, and encourage more extensive investigations using similar methodology in the future. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Limb bone stresses during fast locomotion in the African lion and its bovid preyJOURNAL OF ZOOLOGY, Issue 2 2008B. Sorkin Abstract Peak stresses during fast locomotion in the humerus and tibia of the African lion have been estimated from a filmed prey pursuit sequence and skeletal dimensions of museum specimens; safety factors of the two bones have been calculated. The results are compared with the peak stresses (and the corresponding safety factors) during fast locomotion in the humerus and tibia of large (buffalo) and small (antelope) African bovids, which the lion is known to prey upon, estimated by previous authors using similar methodology. The comparison suggests that both the humerus and the tibia of a running lion have higher safety factors than those of its bovid prey running at the same speed. [source] Prevalence of tic disorder in two schools in the Basque country: Results and methodological caveatsMOVEMENT DISORDERS, Issue 12 2006Gurutz Linazasoro Abstract Different studies have shown that the prevalence of tic disorder is highly variable, depending on the methodology employed. The aim of this study was to determine the prevalence of tic disorder among children of two schools. The study was conducted in three successive steps: information to parents and teachers by way of speeches and projection of videotapes; anonymous fulfilling of an ad hoc questionnaire by teachers and parents and identification of children as "possible tic disorder" according to the questionnaire; and confirmation of the presence of tics by direct observation of children at school (20 minutes in each classroom). Eight hundred sixty-seven children were included. Age ranged from 4 to 16 years. Ninety percent of parents and 99% of teachers fulfilled the questionnaire. Seventy-one children had tics according to parents' and 50 according to teachers' opinion (both coincided in 23 cases). Fifty-seven cases were identified after direct observation in the classroom (prevalence of 6.5%). The vast majority of tics were mild in severity and duration. Prevalence obtained in this study was comparable with data reported in studies using a similar methodology, which is higher than results shown in early studies addressed with less rigid methodology. Most of identified cases were quite mild, not leading to major functional disability. In spite of the methodology employed, it is possible that some cases were lost. © 2006 Movement Disorder Society [source] Carbon black and lung cancer: Testing a new exposure metric in a German cohortAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 8 2007Peter Morfeld PhD Abstract Background A cohort mortality study of a large carbon black production plant in Germany showed an elevation in lung cancer mortality (SMR 1.81 (95% CI: 1.34,2.39)), although the elevation could not be linked to exposure to carbon black. Methods In follow up to a British study of carbon black production workers [Sorahan et al., 2007] in which risk of lung cancer progressively declined after cessation of employment,in contrast to an expected upward trend,we evaluated the German cohort with a similar methodology, that is, by focusing on the first 15 years after leaving employment in terms of lung cancer SMR. Results In our SMR analysis of the German cohort of 1,528 men and an inception cohort of 1,271 men, distinctly different results from the British cohort were observed. We observed a rising trend in lung cancer SMR, in contrast to the declining SMR trend noted in the British cohort. In fact, Cox models for lung cancer mortality with attained age as the basic time variable showed negative coefficients for the full and inception cohorts. Conclusions Our analysis of a large German cohort of carbon black workers does not support the concept of a declining risk of lung cancer following cessation of employment. Am. J. Ind. Med. 50:565,567, 2007. © 2007 Wiley-Liss, Inc. [source] Design and Implementation of a Controlled Clinical Trial to Evaluate the Effectiveness and Efficiency of Routine Opt-out Rapid Human Immunodeficiency Virus Screening in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 8 2009Jason S. Haukoos MD Abstract In 2006, the Centers for Disease Control and Prevention (CDC) released revised recommendations for performing human immunodeficiency virus (HIV) testing in health care settings, including implementing routine rapid HIV screening, the use of an integrated opt-out consent, and limited prevention counseling. Emergency departments (EDs) have been a primary focus of these efforts. These revised CDC recommendations were primarily based on feasibility studies and have not been evaluated through the application of rigorous research methods. This article describes the design and implementation of a large prospective controlled clinical trial to evaluate the CDC's recommendations in an ED setting. From April 15, 2007, through April 15, 2009, a prospective quasi-experimental equivalent time-samples clinical trial was performed to compare the clinical effectiveness and efficiency of routine (nontargeted) opt-out rapid HIV screening (intervention) to physician-directed diagnostic rapid HIV testing (control) in a high-volume urban ED. In addition, three nested observational studies were performed to evaluate the cost-effectiveness and patient and staff acceptance of the two rapid HIV testing methods. This article describes the rationale, methodologies, and study design features of this program evaluation clinical trial. It also provides details regarding the integration of the principal clinical trial and its nested observational studies. Such ED-based trials are rare, but serve to provide valid comparisons between testing approaches. Investigators should consider similar methodology when performing future ED-based health services research. [source] | ||||||||||||||||