The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » sci.math.* » sci.stat.math

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: chi-square in confidence interval for failure rate
Replies: 2   Last Post: Mar 16, 2013 11:44 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]

Posts: 517
Registered: 2/23/10
chi-square in confidence interval for failure rate
Posted: Mar 16, 2013 10:09 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

All the info I found online for estimating failure rate from the
number of failures over a time period make reference to chi-squre, but
without actually describing how it comes about. The most helpful
explanation I found is

However, I'm missing some fundamental intuition behind the starting
point (equation 5). It is assumed that we see r failures over a time
period T. The probabilities for 0 to r failures are summed up and
related to the confidence level. Why is this equation true? I mean,
we do not see 0 to r failures, we only see r failures, so why so those
lesser failure counts come into the picture at all?

Thanks if anyone can refer to an online explanation. If it is
offline, I can probably get it eventually, but online would be so much
more suitable for my timeframe.

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.