The size of the confidence region is determined by the chosen level of confidence. It can be expressed as the probability (i.e., a number between 0 and 1) that the true system can be found within the region.
The probability is computed under the assumption that the estimate has a normal distribution. Alternatively, the confidence region can be expressed as a number of standard deviations. For example, a probability of 0.99 (99%) corresponds to 2.58 standard deviations.
There are three ways to set the confidence level:
Press Apply to compute and plot the new confidence intervals.
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