By setting the smart value to 5 and executing the time series module, the settlement value of PS-InSAR was obtained as the excel data.
However, there are many differences from the last value of the time series and the cumulative displacement.
I know that cumulative displacement analyzes the first and last images using a specific module.
I used 21 TerraSAR-X satellite images.
The images are a period of about one year and six months every 22 days.
In this case, should I look at cumulative displacement as a true value, or should I look at the last value as a true value?
Could you tell me if there is a formal formula for calculating cumulative displacement?
If you use the smart option, the modeled displacement is a non-parametric estimate of the displacement. In other words, the smart option filters the displacement, and the filtered series is the result.
modeled_disp = filter ( displacement )
The cumulative displacement in Sarproz is always calculated based on the model, so
cum_disp = modeled_disp ( end ) – modeled_disp ( beg )
This is why there can be a discrepancy between displacement ( end ) – displacement ( beg ) and cum_disp.
but the discrepancy will be small, of the same order of the noise of your data series