Hors-Série IA 2020



Frequency

In a statistical study, we can collect data about particular characteristics of a population. After this data collection we can draw up tables and graphs.
The frequency of a value is the number of occurrences of this value over the total occurrences of the study. It is the proportion of individuals that possess the characteristic in question.
In the case of a quantitative sequence, in which modalities are grouped in classes, the frequency of a class is the quotient of the number of occurrences belonging to this class divided by the number of total occurrences of the study. It represents the proportion of individuals whose characteristic belongs to the class in question.
The frequency of a modality or class is between 0 and 1. It can also be expressed as a percentage of the total occurrences.
The sum of frequencies of all modalities or all classes should be equal to 1 ( or 100%).