Confidence Intervals for Estimates Based on Linear Regression in Forensic Anthropology

Abstract

Forensic anthropologists commonly use simple linear regression to estimate the value of a dependent variable, such as stature, for a single specimen where the value of the independent variable, such as humerus length, is known. Published studies providing regression equations for such use almost invariably include the standard error of estimate. Unfortunately, it is exceptional for forensic anthropologists to use the standard error to calculate correctly the confidence limits for their single predicted value. We attempt to show why this may be and provide explicit guidelines for the proper construction of confidence interval in such circumstances.