Characterizations of finite sequences $\beta_{1}<\cdots<\beta_{n}$ representing expected values of order statistics from a random sample of size $n$ are given. As a by-product, a characterization of binomial mixtures, when the mixing random variable is supported in the open interval $(0,1)$, is presented; this enables the exact description of the convex hull of the open binomial curve, as well as the open moment curve.

翻译：作为副产品,当混合随机变量在开放间隔值$(0,1)美元中支持混合随机变量时,对二进制混合物进行了定性;这样可以准确描述开放二进制曲线的二次曲线和开放时钟曲线的结壳。