Alberto Monteiro wrote: > I have a time series x = f(t), where t is taken for each > month. What is the best function to detect if _x_ has a seasonal > variation? If there is such seasonal effect, what is the > best function to estimate it? > From my own experience, I had the impression that there is nothing like a best approach to estimate the seasonal component of time series data.
Maybe it is possible for you to simulate the assumed nature of your data (variable trend? variable seasonal pattern? count data with overdispersion? maybe a bimodal pattern every year?) and then try various of these methods and check if they can extract your input approximately correctly? Best, Roland ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.