Confidence interval Vs Prediction interval
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January 2, 2003 at 6:38 am #31116
RavishankarParticipant@Ravishankar Include @Ravishankar in your post and this person will
be notified via email.Hi,
Can anyone please explain what is the differnce between Confidence interval & Prediction interval. I know this much that the former is used for parameters distrinution and the later for future outcomes.
Regards,
Ravishankar S0January 2, 2003 at 4:48 pm #81812Confidence interval is an estimate for population mean (Xbar) whereas prediction interval is for future outcome of an individual value (Xi)
0January 3, 2003 at 6:34 am #81827
John DubucParticipant@jdubuc Include @jdubuc in your post and this person will
be notified via email.For completeness, there are three general types of Interval Estimates: Confidence Intervals, Prediction Intervals, and Tolerance Intervals. Each has associated subtypes for special applications. All three intervals estimate unknowns with a specified (1alpha) degree of confidence.
Confidence Intervals estimate population parameters, and are generally meaningful to the producers of a product.
Prediction Intervals estimate the future value of a single observation (or small number of observations) from a population, and are of interest to the consumers of a product.
Tolerance Intervals estimate a specified proportion of the population. For example we can be 95% confident that at least p% of the population is captured by the sample interval. These estimates are useful in situations where process tolerance limits (specs) are determined by process variability such as in tolerance design.
Its important to remember that the confidence level associated with any of these intervals refers to the procedure used to construct the interval and not the particular interval you calculate from the sample.
Warmest regards0January 7, 2003 at 1:28 pm #81932Why are these intervals inportant? How do you use them?
0January 8, 2003 at 5:13 pm #81997
John DubucParticipant@jdubuc Include @jdubuc in your post and this person will
be notified via email.Here’s a link to get you started using and interpreting statistical intervals:
http://www.itl.nist.gov/div898/handbook/index.htm0February 12, 2003 at 10:06 pm #82956
John TurnerParticipant@JohnTurner Include @JohnTurner in your post and this person will
be notified via email.I think an important distinction between the two types of intervals is that prediction intervals refer to observable quantities, such as future observations. Confidence intervals refer to parameters, such as probability, that cannot be observed, but still describe the process.
If we wish to describe the mean of a distribution, we would use a confidence interval. If we want to put a bound on the next observation from the distribution, we would use a prediction interval.0November 24, 2005 at 11:50 pm #130287excellent responses. huge help. thanks!
0November 25, 2005 at 6:30 am #130298
Guruprasad DeotaleParticipant@GuruprasadDeotale Include @GuruprasadDeotale in your post and this person will
be notified via email.Mr Turner .,
sir,Can u be contacted through mail?if so mail id please .
thanks & regards .,
gsd0November 25, 2005 at 2:35 pm #130305By any chance did you happen to notice the date of the post? It is 2 years old!!!!!!
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