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The following Y2K material has been kept available by MITRE for historical purposes only and has not been updated unless noted.

Confidence Assessment: Quantitative Technique

A presentation and short paper entitled Year 2000 Confidence Assessment - A Bayesian Tutorial, prepared by John Vitkevich, describes an application of Bayes' theorem for assessing the confidence of surviving the Y2K computer date problem. Several key concepts in Bayesian analysis are introduced with geometrical diagrams to help clarify its potential application and improve understanding of the method. Bayesian confidence assessment can be applied at various points between now and the Y2K rollover. When a multi-cycle resolution approach is implemented, prior Y2K confidence estimates can be revised at the completion of each cycle to reflect the most recent results of error testing activities, to obtain improved posterior probability estimates of success. This presentation and paper are available in PDF and HTML format from the 1998 SWEE Conference Proceedings web page, or you can download the briefing locally as [PDF - 38K], and the paper as [PDF - 25K].

The methods described in the above Bayesian tutorial can be applied to real-world Y2K testing situations. Mr. Dennis Mangsen made a presentation on Real-World Use of Bayesian Analysis for Year 2000 Confidence Assessment at the MITRE Software Engineering and Economics Conference in April 1998. This paper and accompanying briefing are also available in PDF and HTML format from the 1998 SWEE Conference Proceedings web page. No simple answer is given, but a quantitative technique is described, which might be useful to a decision maker for understanding what has been accomplished to date. The results of applying such a method depend upon the assumptions and data used in the analysis. The paper raises questions, such as "when are we done?" or "how much testing is enough?".

Another presentation on this subject, "Use of Bayesian Analysis for Year 2000 Confidence Assessment", prepared by Dennis Mangsen, Alan Skillicorn, and John Vitkevich, was given at the Annual International Test and Evaluation Association (ITEA) Conference in Albuquerque, New Mexico on 23 September 1998. The presentation is available from the 1998 ITEA Conference Proceedings web site at http://www.swcp.com/itea98/proceed.htm. The paper identifies the prior information required and dependency of the results on assumptions made.