failure models, nonparametric and robust methods, variance estimation (e.g., jackknife, bootstrap), stress testing, accelerated testing, decision-analytic issues, repair and replacement policies, methods for dependent components, current methods in experimental design, and Bayesian approaches. (Since the application of physics-of-failure and Bayesian models is highly specific to the system at hand, it is not clear that any omnibus approaches to the use of these models could be represented in an updated RAM Primer. However, it might be helpful to suggest the utility of these models and provide a casebook of successful and unsuccessful applications of these models for estimating or evaluating the reliability of defense systems.) The view expressed was that the RAM Primer does not currently serve any set of potential users very well.

Many participants at the workshop believe that, 20 years after its last revision, the RAM Primer is substantially out of date. Jim Streilein observed that in many respects, it was already limited in its utility in 1982. One indication of its obsolescence is that it contains a large section on statistical tables and graphs that provide critical values for tests, whereas today a modest amount of embedded software would provide better information. Other documents may also be obsolete; recall that Paul Ellner called for the updating of Military Handbook 189, on reliability growth modeling. Streilein was concerned more broadly about the training of tomorrow’s reliability analysts.

To address this problem, a number of speakers strongly argued that the RAM Primer should be fully updated, possibly in a substantially different format. The suggestion was that a small planning group be charged with responsibility for deciding the goals and form of a new RAM Primer. The possibilities include (1) a primer, (2) a self-contained introductory text, (3) a set of standards, (4) a handbook, (5) a set of casebooks, and (6) a state-of-the-art reference book that well-educated and well-trained professionals could use to remind themselves of various methods. The form selected depends to some extent on whether the users are likely to be inexperienced junior analysts or experienced analysts. Perhaps several of these forms could be developed simultaneously. One interesting suggestion was for the RAM Primer to be a web-based document with embedded software or be linked to interactive software to carry out the variety of calculations necessitated by modern methods.1 Taking this approach would provide greatly ex-

1  

An example of a handbook constructed in ths manner, the National Institute of Standards and Technology/SEMATECH Engineering Statistics Handbook, can be found at http://www.itl.nist.gov/div898/handbook/toolaids/sw/index.htm.



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