Title
Confidence: Its Role in Dependability Cases for Risk Assessment
Abstract
Society is increasingly requiring quantitative assessment of risk and associated dependability cases. Informally, a dependability case comprises some reasoning, based on assumptions and evidence, that supports a dependability claim at a particular level of confidence. In this paper we argue that a quantitative assessment of claim confidence is necessary for proper assessment of risk. We discuss the way in which confidence depends upon uncertainty about the underpinnings of the dependability case (truth of assumptions, correctness of reasoning, strength of evidence), and propose that probability is the appropriate measure of uncertainty. We discuss some of the obstacles to quantitative assessment of confidence (issues of composability of subsystem claims; of the multi-dimensional, multi-attribute nature of dependability claims; of the difficult role played by dependence between different kinds of evidence, assumptions, etc). We show that, even in simple cases, the confidence in a claim arising from a dependability case can be surprisingly low.
Year
DOI
Venue
2007
10.1109/DSN.2007.29
DSN
Keywords
Field
DocType
dependability case,dependability claim,proper assessment,claim confidence,appropriate measure,different kind,subsystem claim,simple case,dependability cases,difficult role,quantitative assessment,risk assessment,calculus,measurement uncertainty,software reliability,risk management,application software,probability
Dependability,Computer security,Computer science,Correctness,Risk assessment,Risk analysis (engineering),Risk management,Software quality,Confidence interval,Application software,Composability,Distributed computing
Conference
ISSN
ISBN
Citations 
1530-0889
0-7695-2855-4
24
PageRank 
References 
Authors
2.30
2
3
Name
Order
Citations
PageRank
Robin E. Bloomfield122744.91
Bev Littlewood2741105.77
David Wright3474.67