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Representation of Confidence in Assurance Cases Using the Beta Distribution

Lian Duan, Sanjai Rayadurgam, Mats Heimdahl, Oleg Sokolsky, Insup Lee
2016 2016 IEEE 17th International Symposium on High Assurance Systems Engineering (HASE)  
Additionally, by transforming the assurance case into a reasoning structure, we show how confidence calculations can be performed using beta distributions.  ...  Additionally, by transforming the assurance case into a reasoning structure, we show how confidence calculations can be performed using beta distributions.  ...  [4] first proposed the use of the beta distribution to represent confidence in assurance cases.  ... 
doi:10.1109/hase.2016.52 dblp:conf/hase/DuanRHSL16 fatcat:ycb7wr5jvzeylgbd6jhubu3vty

Representing Confidence in Assurance Case Evidence [chapter]

Lian Duan, Sanjai Rayadurgam, Mats P. E. Heimdahl, Oleg Sokolsky, Insup Lee
2015 Lecture Notes in Computer Science  
When evaluating assurance cases, being able to capture the confidence one has in the individual evidence nodes is crucial, as these values form the foundation for determining the confidence one has in  ...  The beta distribution models a variety of shapes and we believe it provides an intuitive way to represent confidence.  ...  His use of a beta distribution to represent confidence supports our view of the same. The beta distribution is not a new concept in the realm of assurance cases.  ... 
doi:10.1007/978-3-319-24249-1_2 fatcat:zmd7lrnvfnd6balf47tudulbxm

A Critique of the Valiant Model

Wray L. Buntine
1989 International Joint Conference on Artificial Intelligence  
It is argued that the current interpretation of this Valiant model departs from common sense and practical experience in a number of ways: it does not allow sample dependent bounds, it uses a worst case  ...  It is claimed that as a result, the current model can produce overlyconservative estimates of confidence and can fail to model the logical induction process as it is often implemented.  ...  An average case analysis, like common sense, tells us that if we pick an apple out of the carton, we can be confident (98.5% in this case) it will be a good apple.  ... 
dblp:conf/ijcai/Buntine89 fatcat:uubl3huytjhurazxd6aqkqd24i

Credibly reaching a reliability target using a model initially constructed by expert elicitation

Lawrence E Pado
2014 Integrating Materials and Manufacturing Innovation  
Countermeasures include replacing point probabilities with beta distributions to incorporate uncertainty, 95% confidence levels, and using a multitude of different types of sensitivity analyses to draw  ...  An important aspect of this program is the use of Bayesian networks (BN) to evaluate risk. The BN is used as a graphical representation of the contributing factors that lead to manufacturing defects.  ...  Determining a 95% confidence value on the model output using Monte Carlo methods Now that all of the model parameters have been replaced by beta distributions, the distribution of the model output can  ... 
doi:10.1186/s40192-014-0020-x fatcat:6rny25y3frgdpjgyadhxeplahq

A Unifying Bayesian Approach for Sample Size Determination Using Design and Analysis Priors [article]

Jane Pan
2021 arXiv   pre-print
cases in our framework.  ...  We work primarily in the context of conjugate Bayesian linear regression models, where we consider the situation with known and unknown variances.  ...  The Beta distribution is often used to represent outcomes tied to a family of probabilities.  ... 
arXiv:2112.03509v1 fatcat:vmeajcxxm5fu3pl4cuhuqtpvba

Two Criteria for Evaluating Risk Prediction Models

R. M. Pfeiffer, M. H. Gail
2010 Biometrics  
The first criterion, the proportion of cases followed PCF(q), is the proportion of individuals who will develop disease who are included in the proportion q of individuals in the population at highest  ...  We propose and study two criteria to assess the usefulness of models that predict risk of disease incidence for screening and prevention, or the usefulness of prognostic models for management following  ...  Acknowledgments We thank the reviewers for many helpful suggestions. AUC=0.753  ... 
doi:10.1111/j.1541-0420.2010.01523.x pmid:21155746 pmcid:PMC3135785 fatcat:iy7j55sczjfhzcb6qlsd6dr46a

Estimation and Control for Industrial Products Reliability under Failure Trials

Kui Wang, Lili Ding, Chaoqun Duan
2020 Shock and Vibration  
To maintain the reliability of products at a desirable status, a reliability control method is presented to monitor the confidence interval of reliability distribution.  ...  The lower limit of confidence interval is maintained above a control limit, which indicates that a corresponding quality-assurance action is preferable.  ...  In the case that the a priori density of R is chosen as a Beta density, we have f R (r) � r k (1 − r) l B(k + 1, l + 1) . (18) For the lower 100α-percent confidence limit on R, R Lower is defined as 1  ... 
doi:10.1155/2020/8810047 fatcat:hh37tvf6erhzvj5y2lqjkbqnim

An investigation of proposed techniques for quantifying confidence in assurance arguments

Patrick J. Graydon, C. Michael Holloway
2017 Safety Science  
The use of safety cases in certification raises the question of assurance argument su ciency and the issue of confidence (or uncertainty) in the argument's claims.  ...  In this paper, we survey and assess proposed techniques for quantifying confidence in assurance arguments.  ...  We thank John McDermid, Andrew Rae, and the branch and directorate reviewers for their feedback on this work.  ... 
doi:10.1016/j.ssci.2016.09.014 fatcat:c3adi6biyjgitfiwbvxucrdi7y

Protein cutoff scanning: A comparative analysis of cutoff dependent and cutoff free methods for prospecting contacts in proteins

Carlos H. da Silveira, Douglas E. V. Pires, Raquel C. Minardi, Cristina Ribeiro, Caio J. M. Veloso, Julio C. D. Lopes, Wagner Meira, Goran Neshich, Carlos H. I. Ramos, Raul Habesch, Marcelo M. Santoro
2009 Proteins: Structure, Function, and Bioinformatics  
Finally, we have shown that coarse-grained residue representations may introduce bias in the analysis of neighbors in cutoffs up to 6.8 Å , with CA favoring alpha proteins and GC favoring beta proteins  ...  This provides an additional argument pointing to the value of 7.0 Å as an important lower bound cutoff to be used in contact analysis of proteins. Proteins 2009; 74:727-743.  ...  ACKNOWLEDGMENTS The authors thank Michael Waisberg, not only by the fecund discussions on subject, but also by his incredible ability of finding rare and old publications.  ... 
doi:10.1002/prot.22187 pmid:18704933 fatcat:q6hoscyl3beehn2m6azy6n46mq

Conservative claims about the probability of perfection of software-based systems

Xingyu Zhao, Bev Littlewood, Andrey Povyakalo, David Wright
2015 2015 IEEE 26th International Symposium on Software Reliability Engineering (ISSRE)  
no claims for the practical realism of the numbers we use).  ...  Finally, we seek to prune the set of prior distributions that the assessor finds acceptable in order that the conservatism of the results is no greater than it has to be, i.e. we propose, and eliminate  ...  The views expressed in this paper are those of the author(s) and do not necessarily represent the views of the members of the C&I Nuclear Industry Forum (CINIF).  ... 
doi:10.1109/issre.2015.7381807 dblp:conf/issre/ZhaoLPW15 fatcat:mj3eeolcqbffxf4mw2swr6gcg4

Multivariate Confidence Calibration for Object Detection [article]

Fabian Küppers, Jan Kronenberger, Amirhossein Shantia, Anselm Haselhoff
2020 arXiv   pre-print
The main difference to related work in the field of classifier calibration is that we also use additional information of the regression output of an object detector for calibration.  ...  In addition, we propose a new measure to evaluate miscalibration of object detectors.  ...  The authors would like to thank Visteon for their support and namely Andreas Wedel for the fruitful discussions.  ... 
arXiv:2004.13546v1 fatcat:e3p3cc5skrdazeds77twcphb3i

Pointwise confidence intervals for a survival distribution with small samples or heavy censoring

Michael P. Fay, Erica H. Brittain, Michael A. Proschan
2013 Biostatistics  
The BPCP may be inverted to create confidence procedures for a quantile of the underlying survival distribution.  ...  In such situations, the Kaplan-Meier estimator is typically used with an asymptotic confidence interval (CI) that can have coverage problems when the number of observed failures is not large, and/or when  ...  The simulations were run using the Biowulf Linux cluster at the National Institutes of Health, Bethesda, MD (http://biowulf.nih.gov). Conflict of Interest: None declared.  ... 
doi:10.1093/biostatistics/kxt016 pmid:23632624 pmcid:PMC3769999 fatcat:rm6k55tzvng4njolh2gfdm3sqm

Probabilistic Logic Programming with Beta-Distributed Random Variables [article]

Federico Cerutti and Lance Kaplan and Angelika Kimmig and Murat Sensoy
2018 arXiv   pre-print
We enable aProbLog---a probabilistic logical programming approach---to reason in presence of uncertain probabilities represented as Beta-distributed random variables.  ...  To understand and accurately manipulate such probability distributions we need a well-defined theoretical framework that is provided by the Beta distribution, which specifies a distribution of probabilities  ...  the case of high uncertainty in the random variables.  ... 
arXiv:1809.07888v3 fatcat:rz3oyfmrdrgpzcqrwzrajjpfpq

Probabilistic Logic Programming with Beta-Distributed Random Variables

Federico Cerutti, Lance Kaplan, Angelika Kimmig, Murat Şensoy
2019 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
We enable aProbLog—a probabilistic logical programming approach—to reason in presence of uncertain probabilities represented as Beta-distributed random variables.  ...  To understand and accurately manipulate such probability distributions we need a well-defined theoretical framework that is provided by the Beta distribution, which specifies a distribution of probabilities  ...  the case of high uncertainty in the random variables.  ... 
doi:10.1609/aaai.v33i01.33017769 fatcat:7c2q6uqzmbhoni343yl3f2zudi

The Utilisation of Probabilistic Risk Assessment in Radiation Oncology

Gordon Sands, Enda F. Fallon, Wilhelm J. van der Putten
2015 Procedia Manufacturing  
The components of each process were critically analysed to ascertain their fault potential. Prostate external beam treatment was used as a case study.  ...  It is highly beneficial in evaluating the effectiveness of the safety system currently in place in Radiotherapy.  ...  Acknowledgements The staff of the Radiation Therapy Department in University Hospital Galway, Ireland.  ... 
doi:10.1016/j.promfg.2015.07.138 fatcat:4l2abxvx35h3fbx4jdwysoappq
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