At its core, the Prophet procedure is an additive regression model with four main components: A piecewise linear or logistic growth curve trend. Prophet automatically detects changes in trends by selecting changepoints from the data . A yearly seasonal component modeled using Fourier series.
Read moreWhat is seasonality Prior scale prophet?
Basically seasonality prior scale is setting the standard deviation for the normal distribution . Higher seasonality prior scale means we are setting a wider normal distribution when sampling for the 2*n terms for our fourier. At the end, the yearly components will be simply the fourier generated dot beta.
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