Uncertainty analysis
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... -- Context, concepts and definitions -- Sources of uncertainty -- Tiered approach to uncertainty analysis ... ... INTRODUCTION 1 -- 1.1 Why uncertainty analysis? ... ... 2.3.2 Variability versus uncertainty 11 -- 2.3.3 Sensitivity analysis 13 -- 3. ... ... tiered level 31 -- 4.2.1 Tier 0 (screening) uncertainty analysis 31 -- 4.2.2 Tier 1 (qualitative) uncertainty ... ... analysis 32 -- 4.2.3 Tier 2 (deterministic) uncertainty analysis 33 -- 4.2.4 Tier 3 (probabilistic) ...
IPCS harmonization project document ; no. 6
xiii, 158 s. : il., tab. ; 30 cm
- MeSH
- hodnocení rizik MeSH
- nejistota MeSH
- sběr dat normy MeSH
- vystavení vlivu životního prostředí MeSH
- Konspekt
- Životní prostředí a jeho ochrana
- NLK Obory
- environmentální vědy
- NLK Publikační typ
- publikace WHO
This article deals with continuous-time Linear Time-Invariant (LTI) Single-Input Single-Output (SISO) systems affected by unstructured multiplicative uncertainty. More specifically, its aim is to present an approach to the construction of uncertain models based on the appropriate selection of a nominal system and a weight function and to apply the fundamentals of robust stability investigation for considered sort of systems. The initial theoretical parts are followed by three extensive illustrative examples in which the first order time-delay, second order and third order plants with parametric uncertainty are modeled as systems with unstructured multiplicative uncertainty and subsequently, the robust stability of selected feedback loops containing constructed models and chosen controllers is analyzed and obtained results are discussed.
- MeSH
- nejistota * MeSH
- programování lineární * MeSH
- Publikační typ
- časopisecké články MeSH
283 s.
Although norms of premarital sex vary cross-culturally, the sexuality of adolescent girls has been consistently more restricted than that of adolescent boys. Three major theories that attempt to explain restrictions on female premarital sex (FPS) concern male, female, and parental control. These competing theories have not been tested against each other cross-culturally. In this study, we do this using a sample of 128 nonindustrial societies and socioecological predictors capturing extramarital sex, paternal care, female status, sex ratio, parental control over a daughter's mate choice, residence, and marriage transactions, while also controlling for phylogenetic non-independence across societies. We found that multiple parties benefit from restrictions on FPS. Specifically, FPS is more restricted in societies intolerant of extramarital sex and where men transfer property to their children (male control), as well as where marriages are arranged by parents (parental control). Both paternity uncertainty (partitioned among marital fidelity and paternal investment) and parent-offspring conflict (prompting parents to control their daughter's sexuality) were identified as possible mechanisms of FPS restrictions. The evidence for female control is ambiguous, mainly because it can be equally well interpreted as both male control and parental control, and because fathers, rather than mothers, are often the primary decision makers about a daughter's mate choice. Our results also emphasize the importance of social roles, rather than stereotyped sex roles, as a more useful approach to understanding the evolution of FPS restrictions.
- MeSH
- dítě MeSH
- fylogeneze MeSH
- lidé MeSH
- mladiství MeSH
- nejistota MeSH
- paternita * MeSH
- rodiče MeSH
- vztahy mezi rodiči a dětmi * MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Cíl: předvést praktické použití softwarové techniky určené k analýze variance - one-way ANOVA - ke dvěma účelům verifikačního procesu: k odhadu nejistoty analytické metody dle dokumentu CLSI (Clinical and Laboratory Standards Institute) C51-A Vol. 32 No. 4 „Expression of Measurement Uncertainty in Laboratory Medicine, Approved Guideline“, 2012 [1] a současně ke zjednodušení postupu verifikace preciznosti měřicího postupu dle CLSI EP15-A2 Vol. 25 No.17 „User Verification of Performance for Precision and Trueness; Approved Guideline, Second Edition“ [2]. Výsledky: aplikace obou normativních postupů je předvedena v praktickém příkladu odhadu nejistoty jedné koncentrační hladiny látkové koncentrace urey v lidském séru (měřená veličina) a současně ke zjednodušenému postupu verifikace preciznosti tohoto měřicího postupu. Verifikační experiment odpovídá dokumentu EP15-A2 a měření se prováděla na jedné koncentrační hladině měřené veličiny vždy ve třech opakováních v průběhu pěti dní. Cíl - diskuse: předvést možnost zjednodušení verifikačního postupu. Závěr: Pomocí techniky one-way ANOVA lze současně provést výpočet nejistoty měření i mezilehlé (celkové) preciznosti.
Objective: To demonstrate the practical use of the „one-way ANOVA“ technique for the expression of measurement uncertainty in laboratory medicine as well as to simplify the process of the user verification of performance for precision according, according to documents CLSI (Clinical and Laboratory Standards Institute), titled as C51-A Vol.32 No.4 „Expression of Uncertainty in Measurement Laboratory Medicine, Approved Guideline“, 2012 [1], next only the C51-A, and according to CLSI EP15-A2 Vol. 25 No.17 document titled as „User verification of Performance for Precision and trueness; Approved Guideline, Second Edition“ [2], hereinafter EP15-A2. Results: The application of both normative practices is demonstrated in the practical example use for the uncertainty method estimation on one concentration level of the urea molar concentration in the human serum (measurand), together with the simplified procedure of the user verification of the method performance for the precision. The verification experiment matches the document EP15-A2, i.e. one measurand level running in 3 replicates on each of the 5 days. The calculation of the measurement uncertainty and the intermediate precision is processed by analyzing components of the variability in the „one-way ANOVA“ technique. Objective - Discussion: to demonstrate the possibility of simplifying the verification process Conclusion: the evaluation using one-way ANOVA technique to estimate the method uncertainty and the user verification of the method performance for the precision as well.
Recent techniques of image analysis brought the possibility to recognize subjects based on discriminative image features. We performed a magnetic resonance imaging (MRI)-based classification study to assess its usefulness for outcome prediction of first-episode schizophrenia patients (FES). We included 39 FES patients and 39 healthy controls (HC) and performed the maximum-uncertainty linear discrimination analysis (MLDA) of MRI brain intensity images. The classification accuracy index (CA) was correlated with the Positive and Negative Syndrome Scale (PANSS) and the Global Assessment of Functioning scale (GAF) at 1-year follow-up. The rate of correct classifications of patients with poor and good outcomes was analyzed using chi-square tests. MLDA classification was significantly better than classification by chance. Leave-one-out accuracy was 72%. CA correlated significantly with PANSS and GAF scores at the 1-year follow-up. Moreover, significantly more patients with poor outcome than those with good outcome were classified correctly. MLDA of brain MR intensity features is, therefore, able to correctly classify a significant number of FES patients, and the discriminative features are clinically relevant for clinical presentation 1 year after the first episode of schizophrenia. The accuracy of the current approach is, however, insufficient to be used in clinical practice immediately. Several methodological issues need to be addressed to increase the usefulness of this classification approach.
- MeSH
- diskriminační analýza MeSH
- dospělí MeSH
- lidé MeSH
- lineární modely MeSH
- magnetická rezonanční tomografie metody MeSH
- mapování mozku MeSH
- mladý dospělý MeSH
- mozek patologie MeSH
- počítačové zpracování obrazu metody MeSH
- psychiatrické posuzovací škály MeSH
- schizofrenie diagnóza MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
... List of Acronyms and Abbreviations XXI -- Part One: Methods for generalized -- COST-EFFECTIVE NESS ANALYSIS ... ... What is Generalized Cost-Effectiveness Analysis? 3 -- 2. Undertaking a study using GCEA 17 -- 3. ... ... Uncertainty in cost-effectiveness analysis 73 -- 7. Policy uses of Generalized CEA 83 -- 8. ... ... WHO-CUOICE activities on Generalized -- Cost-Effectiveness Analysis 107 -- Annex B. ... ... Uncertainty in cost-effectiveness analysis: probabilistic uncertainty analysis and stochastic league ...
XXII, 318 s. : il., tab. ; 23 cm + index.
- MeSH
- analýza nákladů a výnosů MeSH
- ekonomické modely MeSH
- náklady a analýza nákladů MeSH
- náklady na zdravotní péči MeSH
- přidělování zdravotní péče ekonomika MeSH
- rozhodování MeSH
- výdaje na zdravotnictví MeSH
- zdravotní priority MeSH
- Publikační typ
- směrnice MeSH
- Konspekt
- Veřejné zdraví a hygiena
- NLK Obory
- ekonomie, ekonomika, ekonomika zdravotnictví
- management, organizace a řízení zdravotnictví
- NLK Publikační typ
- publikace WHO
Pharmaceutical products as well as active pharmaceutical ingredients (APIs) are checked for levels of elemental contaminants to guarantee medicines administration will not involve the consumption of level of contaminants greater than their maximum admissible intake. However, the conformity decision is affected by the measurement uncertainty function of analytical steps performance, used standards quality and how measurement performance is assessed during method validation. When an ingredient is considered conform, since the measured concentration is lower than the maximum limit, the risk of a false acceptance depends on how close the measured concentration is from the limit and on the measurement uncertainty. The analytical methods used for pharmaceutical analysis should be validated by ICH and USP recommendations, in order to prove measurements are fit for purpose. The validation must also be economically feasible and have an acceptable duration. This work discusses how to evaluate the uncertainty of elemental analysis in pharmaceutical ingredients from data collected during the validation of the analytical method by following ICH guidelines and USP chapters. A top-down uncertainty evaluation based on results from the analysis of a model API intermediate, with the native analyte after spiking at three concentration levels, where analyses are performed by two analysts in two different days, is presented. The impact of the correlation of some uncertainty components of collected results on the uncertainty evaluation is discussed and considered in the calculations. The developed measurement model was checked by a cross-validation procedure where some validation data was randomly removed and used for an independent model control. The developed uncertainty evaluation methodology was successfully applied to the analysis of Pd in a model API intermediate by ICP-MS after a micro-wave assisted acid digestion, where the risk of a false acceptance of the pharmaceuticals is determined. The measurement performance data and used spreadsheet are made available as Supplementary Material.
- MeSH
- kontaminace léku MeSH
- léčivé přípravky * MeSH
- nejistota MeSH
- referenční standardy MeSH
- spektrální analýza MeSH
- Publikační typ
- časopisecké články MeSH
A tutorial and spreadsheet for the validation and bottom-up uncertainty evaluation of quantifications performed by instrumental methods of analysis based on linear weighted calibrations is presented. The developed tool automatically assesses if calibrator values uncertainty is negligible given instrumental signal precision, assesses signal homoscedasticity by the Levene's test, guides the selection of weighting factors and evaluates the fitness of the regression model to define the calibration curve. The spreadsheet allows the use of the linear weighted regression model without the need for collecting many replicate signals of calibrators and sample by taking previously developed detailed models of signal precision variation in the calibration interval after adjustments to the daily precision conditions. This tool was successfully applied to the determination of the mass concentration of Cd, Pb, As, Hg, Co, V and Ni in a nasal spray by ICP-MS after samples dilution and acidification. The developed uncertainty models were checked through the analysis of nasal sprays after spiking with known analyte concentration levels. The metrological compatibility between estimated and reference analyte levels for 95% or 99% confidence level supports uncertainty model adequacy. The spiked samples were quantified from many replicate signals but uncertainty evaluation from duplicate calibrator and sample signals was assessed by randomly selecting calibrators and sample signals and by numerically defining a minimum acceptable success rate of the compatibility tests. The developed model was proven adequate to quantify the uncertainty of the studied measurements.
- MeSH
- kalibrace MeSH
- lineární modely MeSH
- nejistota MeSH
- nosní spreje * MeSH
- spektrální analýza MeSH
- Publikační typ
- časopisecké články MeSH
The main aim of this article is to present a graphical approach to robust stability analysis for families of fractional order (quasi-)polynomials with complicated uncertainty structure. More specifically, the work emphasizes the multilinear, polynomial and general structures of uncertainty and, moreover, the retarded quasi-polynomials with parametric uncertainty are studied. Since the families with these complex uncertainty structures suffer from the lack of analytical tools, their robust stability is investigated by numerical calculation and depiction of the value sets and subsequent application of the zero exclusion condition.
- MeSH
- algoritmy MeSH
- nejistota * MeSH
- teoretické modely * MeSH
- Publikační typ
- časopisecké články MeSH