Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and AnswersTopic Posted by: Reliability & Maintainability Forum (firstname.lastname@example.org )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Original Message:Posted by: Leroy Meyers
Date posted: Mon Mar 5 15:51:46 US/Eastern 2007
Subject: Field Data & MTBF
I have field data over a period of many years, and I want to calculate the MTBF with a confidence level. Would it be correct to use the Chi Square distribution? If so, would the Degrees of Freedom be 2n+2 (where n=number of failures)as if it were a time-truncated test?
I'm looking at page 38 of Practical Statistical Tools for the Reliability Engineer.