Calculating confidence intervals in parameter estimation: a case study

A method to construct simultaneous confidence intervals for least squares estimates is described. The calculation of one-at-a-time confidence intervals is very popular and straight-forward. However, one-at-a-time confidence intervals result in lower confidence levels than anticipated. Simultaneous confidence intervals are more difficult to construct, but are more theoretically sound. A power engineering state estimation application is shown; both types of confidence intervals are constructed using actual data.