The Fano factor, defined as the variance-to-mean ratio of spike counts in a time window, is often used to measure the variability of neuronal spike trains. However, despite its transparent definition, careless use of the Fano factor can easily lead to distorted or even wrong results. One of the problems is the unclear dependence of the Fano factor on the spiking rate, which is often neglected or handled insufficiently. In this paper we aim to explore this problem in more detail and to study the possible solution, which is to evaluate the Fano factor in the operational time. We use equilibrium renewal and Markov renewal processes as spike train models to describe the method in detail, and we provide an illustration on experimental data.

中文翻译：

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Fano 因子：潜在有用的信息

Fano 因子定义为时间窗口中尖峰计数的方差与均值比，通常用于测量神经元尖峰序列的可变性。然而，尽管其定义透明，但不小心使用 Fano 因子很容易导致扭曲甚至错误的结果。问题之一是Fano因子对尖峰率的依赖不明确，这往往被忽视或处理不充分。在本文中，我们旨在更详细地探讨这个问题并研究可能的解决方案，即评估运行时间中的 Fano 因子。我们使用平衡更新和马尔可夫更新过程作为尖峰列车模型来详细描述该方法，并提供了实验数据的说明。