I have count data (non-financial) from 2010-2014 by week. I am interested in using R and changepoint package to find any significant points of time when the trend changed. I have two questions about implementing change point given that it is searching to significant change to the mean. The data is non-stationary (some trends) and additive.
- Should I take the differencing of the count?
- How do I handle the 53 weeks during leap year?