Quantitative methods are based on two indissociable elements:

• the methods,
• the data processed using these methods.

The methods are intended to describe facts. These methods are referred to as descriptive statistics. They can also focus on verifying theoretical elements; this consists of testing and verifying statistical models. Finally, they can focus on establishing methods of prediction based on theoretical statistical models developed following empirical observations. Research using quantitative methods consists of numerically representing or manipulating observations in order to describe and explain the phenomenon that these observations report. Research using qualitative methods refers to the non-numerical examination and interpretation of observations, in order to identify underlying explanations and modes of interrelation.