premature to draw conclusions on the basis of the panel's in-depth examination of only a few systems. However, we believe that the systems we have studied are illustrative of best current practice. We are confident that our recommendations have applicability beyond the systems that we examined.

The defense testing community views statistics mainly as estimating means or percentages and of testing hypotheses. These are important and valuable tools, but they are often too simple to deal with important and complex issues involving enormous costs. Even when these tools are used, the expected costs and benefits must be evaluated for each competing strategy, and must be used in deciding what experimentation to do and how much to spend on it.

The panel has been told many times that the "statistical answer" is prohibitively expensive and so cannot be used. This often reflects severely reduced budgets determined without proper consideration of costs and benefits. The response should not be to disregard the statistical approach, but to use it either to evaluate what is the best that can be done under the given financial constraints, or to reset the constraints.

The complex problems arising in operational testing require sophisticated and well trained statisticians who understand how to develop methods appropriate for the underlying problems.

The report outlines the statistical methods that, both in the short-and long-term, will have a dramatic effect on the quality of defense systems acquired by DoD, and the costs of this acquisition. These include new approaches to software testing, new methods for test design for reliability, availability, and maintainability, methods for validation of modeling and simulation, and methods for obtaining more information from operational and other testing. This also includes a new view for the role of testing as part of military system development. In addition, the panel believes that a regular interaction between the statistical and defense testing communities must be established so that new statistical techniques and applications will be developed specifically tailored to meet the challenges unique to defense testing and evaluation.



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