Margin of Error
When a statistic is
used to estimate a parameter, it is common to compute
a confidence
interval.
The margin of error is the difference between the statistic and the endpoints
of the interval. For example, if the statistic were 0.6 and the confidence interval
ranged from 0.4 to 0.8, then the margin of error would be 0.20. Unless otherwise
specified, the 95% confidence interval is used.