Assessing measurement error in paleozoological osteometrics with bison remains

Abstract

Paleozoologists seldom consider how measurement error affects their osteometric data. This error may vary between measured dimensions or with degrees of physical deterioration. We investigate this problem with a paleontological sample of five bison radii displaying different levels of physical deterioration. We instructed twelve students to repeatedly measure two dimensions on each radius. The measurement data reveal between dimension variability in how well students repeat their own measurements and variability in how well they reproduce each other's measurements. Further, for one dimension, physical deterioration affects measurement repeatability and reproducibility. Our results suggest that analysts should exercise more care in selecting which bones they include in metric studies of fossil bison. Further, in paleozoological studies generally, analysts should calculate measurement errors using the most weathered and error prone specimens that they wish to include in a measured sample. When possible, these errors should be a product of repeated measurements by multiple analysts to ensure reproducibility.