Anonymize data

Sometimes you need to prepare a dataset that conveys the data structure and patterns but does not contain the real data points. This is what the "Anonymize Data" feature is for.

The data in the selected columns gets replaced with anonymized values. The new value depends on the column type and the old value:

• Categorical. If the categories are defined for the specified column, the value is replaced with a random category. Otherwise, the value is replaced with the synthetic category (such as ' race 5' for the 'race' column). To choose a category, click on the corresponding cell in the ' category' column. Note that a table containing exactly one string column (representing a category) has to be imported before opening data anonymization dialog.

• Numerical. The number gets randomly changed. The scale of the change depends on the specified number randomization factor r. The actual formula is:

  newValue = col[i] * math.pow(10, 2 * r * rnd.nextDouble() - r)

For selecting a random subset of the (possibly already anonymized) dataset, see Selecting random rows.