In statistics, the Bhattacharyya coefficient is a measure of the statistical separability of classes, giving an estimate of the probability of correct classification.

The Bhattacharyya coefficient is a divergence-type measure which has a straightforward geometric interpretation. It is the cosine of the angle between n-dimensional vectors.

References

A. Djouadi, O. Snorrason and F. Garber, "The quality of Training-Sample estimates of the Bhattacharyya coefficient", IEEE Tran. Pattern analysis and machine intelligence, vol. 12, pp. 92-97, 1990.