Reliability/Quality Guru, I received this question from our engineering department. Currently, they are seeing 1 system crash out of 10 times. They want to improve the crash rate to 1 failure every 30 times with 90% confidence level. They want to know how many operation "X" they will run with no more than "Y" failures with 90% confidence level which will yield 1 failure every 30 times. I do not know how to solve it as haven't practiced it. Am I providing enough information or what information is needed to make a sense out of it? What kind of model it will fit, Poisson, Binomial, etc? Any help will be highly appreciated. re, ken patel ______________________________________________________ Ken Patel Phone: (408) 490-6804 1708 McCarthy Blvd. Fax: (408) 490-6859 Milpitas, CA 95035 Beeper: (888) 769-1808 ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################