Undo

Microdata anonymization is a trial-and-error process. It is necessary to several methods, each with different parameter settings, to find optimal set of anonymization measures that minimize the information loss, while reducing the risk of disclosure to an acceptable level. Before applying an alternative method to the same variable or set of variables, it is important to undo the previously applied methods. Only in this way, it is possible to compare the effect on risk and information loss of a particular method or parameter setting. For instance to compare the effect of recoding the age variable in 5 or 10 year intervals, it is necessary to first undo the recoding in 5-year intervals before recoding in 10 year intervals.

In sdcApp it is possible to undo the last anonymization step. In order to undo several steps, it is required to save and reload the SDC problem. Both ways are explained below.

Undo one step

In order to undo one step, go to the Undo tab. The screen shows

risk measures etc are also reset, script not (completely), random seed not

Undo several steps

Save and reload

Recommended to save the SDC problem after each method to be able to reload. This is also practical if sdcApp or R crash. Also useful to continue working at a later point of transfer a problem to a different computer

Save a previously saved problem

Load a previously saved problem

Note

sdcApp exports four different file types Different file names for different files (data, sdcProblem)