I am doing time series analysis using R. I have to decompose my data into trend, seasonal and random component. I have weekly data for 3 years. I have found two functions in R —
stl()
anddecompose()
. I have read thatstl()
is not good for multiplicative decomposition. Can anybody tell me in what scenario these functions can be used?
Answer
I would say STL
. STL does trend and seasonal see: http://www.wessa.net/download/stl.pdf
Decompose only does seasonal see the documentation here: http://stat.ethz.ch/R-manual/R-devel/library/stats/html/decompose.html
When you work with them be sure to include your trend type (multiplicative, additive) and season type (multiplicative, additive). Trends can also sometimes have a damping factor too.
By multiplicative decomposition I assume you mean in the case for trend. You are not likely to use multiplicative decomposition unless you are decomposing a exponential growth function.
Attribution
Source : Link , Question Author : Arushi , Answer Author : sfjac