 Weak Convexity Suppose \(\mathfrak{I}\) is a legitimate inaccuracy measure. Then if \(c \neq c'\) and \(\mathfrak{I}(c, w) = \mathfrak{I}(c', w)\), then   \[\mathfrak{I}\left(\frac{1}{2}c + \frac{1}{2}c', w\right) \leq \mathfrak{I}(c, w) = \mathfrak{I}(c', w)\]