Technical note: Issues with proposed chance match probabilities in barefoot morphology

Several chance match probabilities have been proposed with regards to barefoot morphology. Unfortunately, those assessed in this technical review have critical errors. Some directly assume that the data collected from bare feet are independent. One article, the main discussion point, attempts to use principal component analysis (PCA) to circumvent the issue of dependent data. The authors claim that PCA generates new statistically independent variables. PCA creates new variables which are linearly orthogonal and maximally preserve the variance from the data; however, it does not create statistically independent variables. This technical note highlights the flaws with these arguments; therefore, these proposed chance match probabilities should not be used to support the scientific foundation of the discipline.