lightweight_mmm
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media_priors
Hi All,
I have some questions about setting the media_priors.
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Is there a way to change the default HalfNormal distribution to something else, say, Gamma? I ask because suppose I have reason to believe that the PDF should peak at certain positive value (but we know that the HalfNormal is zero-biased).
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Why do we 1-center the costs? What happens if I do not 1-center it? Especially when the costs do not even go into the model as training data but are only used to set the default media_priors. I can understand the reason behind 1-centering the dependent and independent variables of the model. But why the media_priors?
I have the same questions here.
For question 2, I'm not sure what the underlying principle for 1-centering. In our case, 1-centering results in a higher marketing contribution as compared to dividing the media spend by the max value.