The missing mass refers to the probability of elements not observed in a sample, and since the work of Good and Turing during WWII, has been studied extensively in many areas including ecology, linguistic, networks and information theory. This work determines what is the \emph{maximal variance of the missing mass}, for any sample and alphabet sizes. The result helps in understanding the missing mass concentration properties.

翻译：缺失质量是指在样本中未观察到元素的概率,而且自二战期间Good和Turing的工作以来,在许多领域,包括生态学、语言学、网络和信息理论方面,已经对Good和Turing的工作进行了广泛研究。这项工作决定了任何样本和字母大小的缺失质量的最大差异。结果有助于理解缺失的质量浓度属性。