文档介绍：Chapter 5 Description of categorical data
Content
Rate、proportion and ratio
Application of relative numbers
Standardization of rate
Dynamic series and analysis index
Section 1 Relative Numbers
1、Rate
2、Proportion
3、Ratio
1、Rate
Rate:To describe the frequency or intension of some phenomenon.
=
Number of individual occurred some thing within a period of time
Rate
The whole number of likely to occurred some thing in the same period
Example1 To investigate 8589 old people in some city in 1998, and 2823 people had hypertension.
Morbidity rate:
2823 / 8589 100% = %
2、Proportion
Proportion: To describe the ratio of number of one part and the whole number in the same thing.
Formula:
100%
=
Number of individuals in one part
Proportion
The whole number of individuals
Example2 Calculate the patients proportion of 5 diseases in one hospital in 1990 and 1998.
Example2 Calculate the patients proportions of 5 diseases in one hospital in 1990 and 1998.
Characteristics:
(1)Summation of proportions in one thing is 100%.
(2)Proportions in the same thing are interactional.