We review the cumulant decomposition (a way of decomposing the expectation of a product of random variables (e.g. $\mathbb{E}[XYZ]$) into a sum of terms corresponding to partitions of these variables.) and the Wick decomposition (a way of decomposing a product of (not necessarily random) variables into a sum of terms corresponding to subsets of the variables). Then we generalize each one to a new decomposition where the product function is generalized to an arbitrary function.

翻译：我们回顾了累积量分解（将随机变量乘积的期望，例如$\mathbb{E}[XYZ]$，分解为对应于这些变量划分的项之和的方法）和Wick分解（将（不一定随机的）变量乘积分解为对应于这些变量子集的项之和的方法）。随后，我们将每种分解推广至一种新的分解形式，其中乘积函数被泛化为任意函数。