Definition
For the Poisson distribution the mean and variance are not independent: . The Anscombe transform
aims at transforming the data so that the variance is set approximately 1 whatever the mean. It transforms Poissonian data to approximately Gaussian data of standard deviation 1. This approximation is valid provided that the mean value of the Poissonian data is larger than 4.
Read more about this topic: Anscombe Transform
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