During World War I, the national air services involved developed their own methods of assessing and assigning credit for aerial victories. For various reasons, all belligerents engaged in overclaiming aerial victories to a greater or lesser degree.[1] The accuracy of reported aerial victories varied widely according to definitions and terminology, how strict the standards of verification were defined and upheld, and how well they were able to control for all sorts of cognitive biases in assessing the evidence of aerial victory claims.[1]