Details on soft decision trees

In Distilling a Neural Network Into a Soft Decision Tree the authors mention

exponentially decaying running average of the actual probabilities with a time window

but provide no formula for it.

What does it mean speaking formal?

• Interesting paper. Note that in this question you are referring to how the tree is built in order to help distile the knowledge in a NN Dec 19 '20 at 9:50

ma_new = alpha * new_sample + (1-alpha) * ma_old

Where alpha is the parameter that controls rate of decay, between 0.0-1.0.