Why do I find a lot of 3s in birth, death, and hospital admission tables I create in Module 3 (Two-way Tables) and in the AIDS data in Module 1 or 2?
In order to maintain the confidentiality of birth, death, and hospital admission records, values between 1 and 5 cases are suppressed in birth, death, and hospital admission cross-tabulations and values smaller than 5 (including 0!) are suppressed in the AIDS data.. In order to avoid creating problems when users import these tables into spreadsheets and other software packages, a “3” or “2” is placed into these cells instead of some character such as an asterisk.
