sarproz-group

Differences and Correlation between Cumulative Displacement and final value.

This topic contains 2 replies, has 2 voices, and was last updated by  leewoneung 9 months ago.

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  • #2866

    leewoneung
    Participant

    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?

    Warmest regards,

    Mr.LEE

  • #2867

    periz
    Keymaster

    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
    best

  • #2868

    leewoneung
    Participant

    I would like to see the settlement of PS points over time. So is it better to use a time-series analysis rather than a cumulative displacement??

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