•Second
step: use methods to lessen the chance of re-identifying
individuals from “unique” combinations of variables, e.g.,
–Releasing
a random subsample;
–Limiting
geographic detail;
–Reducing
the number of "unusual cases" (examples of
methods used include rounding, recoding categorical responses, using
ranges for age rather than exact age or date of birth);
and
–Increasing
the uncertainty associated with data (i.e., data swapping, adding random
noise).