Statistics-based methods

In previous editions of this textbook a number of methods of determining causality have been described and an attempt made to evaluate their relative reliability and validity. It has to be understood that such statistically based methods have, over several dacades, been in competition with common observation and inspired guesswork for the assessment of adverse effects in respect of the need for regulatory action. This is not just a matter of idiosyncratic personal preference but is frequently imposed by the clinical and numerical evidence available. 

The QA SOP manual should describe QAU audit and inspection techniques with attached inspection checkhsts, if used. Statistically based methods for random selection of phases of studies for inspection and for random selection of data points during final report audits should be described and justified. Any designation of study phases as critical or noncritical used to estabhsh the frequency of study inspec-... 

Tiers can be generally described by the use of fixed UFs, statistically based methods, mechanistic methods, and/or experimentation in physical models (e.g., mesocosms). 

The counting technique was based on the truncated multiple traverse technique as described by Sichel. This is a statistically based method of selecting and counting fields in a stratified manner which improves reliability, minimizes the... 

France FBI Multimetrics (7) Official A statistical based method, close to the... 

Belgium Flan- Multimetrics (8 Official A statistical based method explained... 

This chapter presented a statistically based method for validating neutralizing systems used in topical antimicrobial efficacy evaluations. This method should be performed prior to performing a topical antimicrobial efficacy evaluation so that the researcher can be assured that the neutralizing system to be used will,... 

The development of embrittlement correlation methods is schematically illustrated in Rg. 11.1, where embrittlement correlation methods are very roughly classified into two groups as mentioned above statistically-based methods and mechanism-guided methods. Most of the embrittlement correlation methods authorized by the regulatory bodies are statistically-based, but the EONY model which is used in the US alternative PTS rule. 

The objective of studying statistical methods for component life prediction is to develop statistically-based methods to a< ourately predict strength and lives, and confidence intervals for the predictions. Some key areas targeted for development include ... 

It is important to point out that these statistically based methods will only properly calculate uncertainties that arise from random errors. They do not calculate potential errors that can arise from insufficient sampling of local energy minima, as can occur when the energy surface consists of multiple minima separated by non-negligible energy barriers. In order to determine reliable free energies, one must ensure not only that the statistical error is small, but also that all relevant minima are being sampled. ... 

Note that there is a proportionality constant in Eq. 19. This constant can be evaluated by imposing the constraint that the sum of the values of F corresponding to the m different damage parameters should be equal to unity. This condition is similar to that in Eq. 16, with the difference being that now the posterior probabilities need to be normalized. Note that the notion of posterior probabilities was absent while Eq. 16 was presented in the classical statistics-based method. Therefore, the advantage of the Bayesian approach is that such posterior probabilities can... 

This chapter presented computational methods to quantify the xmcertainty in structural health monitoring, by considering the three steps of damage diagnosis, i.e., damage detection, damage localization, and damage quantification. Classical statistics-based methods and Bayesian methods... 

IS.4.1 A statistically based method for calculation of reproducibility between different methods was developed as listed below ... 

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