Introduction

In Privacy-Preserving Data Publishing the protection of privacy depends on generalization. The more general value is used the the better protection for privacy. However generalizing data too much will cause too high distortion and therefore render it useless for dataminers. For example generalizing person's age to interval with step of 5 would be normally offer sufficient protection while generalizing age to interval with size of 20 can cause too much distortion. In addition to numerical values categorical values are also generalized.

For example: if in some case Job is part of QID we can generalize tester, programmer and developer to information technology and surgeon, family doctor and nurese to medicine. If for some reason this generalization does not offer sufficient protection to privacy it can be further generalized to 'any job'.

Getting started

Your task is to decide how much generalization is needed. Depending on whether you have numerical values or categorical values you need to either specify interval size or add generalization rules.

• If you have numeric values follow these steps:
1. Write the size of interval under Select interval size.
• To help you to decide which interval is best there are 2 labels given to you: min which tells you the smallest value for this column and max which tells you the largest value in this column. For example if you are generalzing column age and min is 18 and max is 65 it means that the youngest person in this table is 18 years old and the oldestst is 65 years old.
2. Click next button.
• If you have categorical values follow these steps:
1. define general value for each value.
   1. Below the text box you see different values from that column (in purple boxes). Start clicking on similar values to group them into one rule.
   2. Once you have grouped together all the similar values, click on Set generalization for this rule.
   3. Under Please specify general value for these values enter the more general value. For example, if you have previously clicked on programmer, tester and developer you might want to enter information technology there.
   4. Click ok to close input box.
   5. If you have any unused values (purple boxes) left, repeat steps 1.1 - 1.4. For example if you are generalizing job and you previously generalized programmer, tester and developer to information technology, you might now want to generalize surgeon, family doctor and nurese to medicine
2. Click next button.