Empiricism is at the heart of all scientific analysis.  The  scientific method  is the name for the ongoing process that economists, other social scientists, and natural scientists use to:  
1.  Develop models of the world  
2. Test those models with data—evaluating the match between the models and the data

A  model  is a simplified description, or representation, of the world. Sometimes, economists will refer to a model as a  theory. These terms are often used interchangeably.