Calculating MTTF When You Have Zero Failures
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چکیده
How do you calculate the MTTF (Mean Time To Failure) when you have zero failures? If you use the standard equation for MTTF, which is the ratio of total testing time and the number of failures, you get an answer of infinity. In such cases, you define a confidence level between 0 and 100 and then compute the lower bound chi-square value using two degrees of freedom. The equation for calculating MTTF for zero failures is given by:
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