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Third Approach (third + approach)
Selected AbstractsCountry specific cost comparisons from multinational clinical trials using empirical Bayesian shrinkage estimation: the Canadian ASSENT-3 economic analysisHEALTH ECONOMICS, Issue 4 2005Andrew R. Willan Abstract The growing number of multinational clinical trials in which patient-level health care resource data are collected have raised the issue of which is the best approach for making inference for individual countries with respect to the between-treatment difference in mean cost. We describe and discuss the relative merits of three approaches. The first uses the random effects pooled estimate from all countries to estimate the difference for any particular country. The second approach estimates the difference using only the data from the specific country in question. Using empirical Bayes estimation a third approach estimates the country-specific difference using a variance-weighted linear sum of the estimates provided by the other two approaches. The approaches are illustrated and compared using the data from the ASSENT-3 trial. Copyright © 2005 John Wiley & Sons, Ltd. [source] Improving the analysis of movement data from marked individuals through explicit estimation of observer heterogeneityJOURNAL OF AVIAN BIOLOGY, Issue 1 2010Fränzi Korner-Nievergelt Ring re-encounter data, in particular ring recoveries, have made a large contribution to our understanding of bird movements. However, almost every study based on ring re-encounter data has struggled with the bias caused by unequal observer distribution. Re-encounter probabilities are strongly heterogeneous in space and over time. If this heterogeneity can be measured or at least controlled for, the enormous number of ring re-encounter data collected can be used effectively to answer many questions. Here, we review four different approaches to account for heterogeneity in observer distribution in spatial analyses of ring re-encounter data. The first approach is to measure re-encounter probability directly. We suggest that variation in ring re-encounter probability could be estimated by combining data whose re-encounter probabilities are close to one (radio or satellite telemetry) with data whose re-encounter probabilities are low (ring re-encounter data). The second approach is to measure the spatial variation in re-encounter probabilities using environmental covariates. It should be possible to identify powerful predictors for ring re-encounter probabilities. A third approach consists of the comparison of the actual observations with all possible observations using randomization techniques. We encourage combining such randomisations with ring re-encounter models that we discuss as a fourth approach. Ring re-encounter models are based on the comparison of groups with equal re-encounter probabilities. Together these four approaches could improve our understanding of bird movements considerably. We discuss their advantages and limitations and give directions for future research. [source] Hegel, Human Rights, and ParticularismJOURNAL OF LAW AND SOCIETY, Issue 4 2003Richard Mullender Hegel's political philosophy gives prominence to the theme that human beings have a need for recognition of those qualities, characteristics, and attributes that make them distinctive. Hegel thus speaks to the question whether human rights law should recognize and accommodate the nuances of individual make-up. Likewise, he speaks to the question whether human rights law should be applied in ways that are sensitive to the cultural contexts in which it operates. But Hegel's political philosophy evaluates norms and practices within particular cultures by reference to the higher-order and universal criterion of abstract right. In light of this point and the inadequacies of political philosophy that privileges local norms and practices, a third approach to the protection of human rights is canvassed. This approach prioritizes neither universal nor local norms. Its aim is to ensure that both human rights and the cultures in which they are applied are taken seriously. [source] New approaches for predicting protein retention time in hydrophobic interaction chromatography,JOURNAL OF MOLECULAR RECOGNITION, Issue 4 2006M. E. Lienqueo Abstract Hydrophobic interaction chromatography (HIC) is an important technique for the purification of proteins. In this paper, we review three different approaches for predicting protein retention time in HIC, based either on a protein's structure or on its amino-acidic composition, and we have extended one of these approaches. The first approach correlates the protein retention time in HIC with the protein average surface hydrophobicity. This methodology is based on the protein three-dimensional structure data and considers the hydrophobic contribution of the exposed amino acid residues as a weighted average. The second approach, which we have extended, is based on the high correlation level between the average surface hydrophobicity of a protein's hydrophobic interacting zone and its retention time in HIC. Finally, a third approach carries out a prediction of the average surface hydrophobicity of a protein, using only its amino-acidic composition, without knowing its three-dimensional structure. These models would make it possible to test different operating conditions for the purification of a target protein by computer simulations, and thus make it easier to select the optimal conditions, contributing to the rational design and optimization of the process. Copyright © 2006 John Wiley & Sons, Ltd. [source] Beyond top-down and bottom-up work redesign: Customizing job content through idiosyncratic dealsJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 2-3 2010Severin Hornung Two established approaches to work redesign are formal top-down interventions and proactive bottom-up job crafting. Top-down approaches are limited in their ability to create individually optimized work characteristics, whereas bottom-up processes are constrained by the latitude workers have to modify their own jobs. Following recent research on the idiosyncratic deals (i-deals) individuals negotiate with their employer, task i-deals customizing job content are suggested as a third approach to work redesign. Hypotheses on antecedents and consequences of task i-deals were tested in two studies conducted in the United States and Germany using structural equation modeling. LMX related positively to the extent of successfully negotiated task i-deals, which, in turn, was associated with a more positive evaluation of work characteristics,specifically, higher complexity and control and lower stressors. Work characteristics mediated positive indirect effects of task i-deals on employee initiative and work engagement. Denied requests for task i-deals were associated with a more negative assessment of work characteristics. We conclude with theoretical, practical, and research implications for better understanding and implementing work redesign through i-deals. Copyright © 2010 John Wiley & Sons, Ltd. [source] Comparison of Raman spectroscopic methods for the determination of supercooled and liquid water temperatureJOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2005Dubravko Risovi Abstract Raman spectroscopy provides an efficient method for non-contact determination of liquid water temperature with high spatial resolution. It can be also used for remote in situ determination of subsurface water temperature. The method is based on temperature-dependent changes of the molecular OH stretching band in the Raman spectra of liquid water. These in turn are attributed to a decrease in intermolecular hydrogen-bonding interactions with increase in temperature. Here, the results of an experimental study employing three different approaches in the determination of temperature from recorded OH stretching band in the Raman spectra of liquid and supercooled water are presented and discussed. The first two methods are based on deconvolution of the spectral band into Gaussian components whose intensities and associated specific spectral markers are temperature dependent, and the third approach is based on Raman difference spectroscopy (RDS). The presented measurements were conducted on distilled and deionized supercooled and liquid water in the temperature range between ,12.5 and +32.5 °C. The results are compared in terms of linearity of response, sensitivity and accuracy. It is shown that the method based on RDS even in the supercooled temperature range provides better accuracy (the standard deviation from the true temperature is ±0.4 K) and linearity in temperature determination than more complicated methods based on Gaussian deconvolution of the OH stretching band. Copyright © 2005 John Wiley & Sons, Ltd. [source] Estimating breast cancer-specific and other-cause mortality in clinical trial and population-based cancer registry cohortsCANCER, Issue 22 2009James J. Dignam PhD Abstract BACKGROUND: To compute net cancer-specific survival rates using population data sources (eg, the National Cancer Institute's Surveillance, Epidemiology, and End Results [SEER] Program), 2 approaches primarily are used: relative survival (observed survival adjusted for life expectancy) and cause-specific survival based on death certificates. The authors of this report evaluated the performance of these estimates relative to a third approach based on detailed clinical follow-up history. METHODS: By using data from Cancer Cooperative Group clinical trials in breast cancer, the authors estimated 1) relative survival, 2) breast cancer-specific survival (BCSS) determined from death certificates, and 3) BCSS obtained by attributing cause according to clinical events after diagnosis, which, for this analysis was considered the benchmark "true" estimate. Noncancer life expectancy also was compared between trial participants, SEER registry patients, and the general population. RESULTS: Among trial patients, relative survival overestimated true BCSS in patients with lymph node-negative breast cancer; whereas, in patients with lymph node-positive breast cancer, the 2 estimates were similar. For higher risk patients (younger age, larger tumors), relative survival accurately estimated true BCSS. In lower risk patients, death certificate BCSS was more accurate than relative survival. Noncancer life expectancy was more favorable among trial participants than in the general population and among SEER patients. Tumor size at diagnosis, which is a potential surrogate for screening use, partially accounted for this difference. CONCLUSIONS: In the clinical trials, relative survival accurately estimated BCSS in patients who had higher risk disease despite more favorable other-cause mortality than the population at large. In patients with lower risk disease, the estimate using death certificate information was more accurate. For SEER data and other data sources where detailed postdiagnosis clinical history was unavailable, death certificate-based estimates of cause-specific survival may be a superior choice. Cancer 2009. © 2009 American Cancer Society. [source] | |||||||||||||