Definition of Empirical Research

Quantitative Methods
Quantitative empirical research methods are often used to collect information and draw conclusions through numerical data. Quantitative methods are usually predetermined and are set in a more structured format. Some good examples include

1. 
   Surveys
   
2. 
   Longitudinal studies
   
3. 
   Cross-sectional studies
   
4. 
   Experimental research
   
5. 
   Causal comparative research
   

The above techniques are often more effective for physics or medicine.
Qualitative Methods
Qualitative empirical research methods, on the other hand, are used to gather non-numerical data. They are mainly unstructured or semi-structured and are used to find meaning or underlying reasons for a particular phenomenon. In other words, they are used to provide more insight into the problem being researched. So, is qualitative research empirical? The short answer to that is yes. It is indeed empirical but more appropriate in finding answers to social science-related questions.
Types of Empirical Research
Note, there is a difference between methodologies and types of empirical research. Methodologies are the earlier mentioned quantitative and qualitative, and they refer to the methods used to conduct or analyze data. But when it comes to types of empirical research, it can be either experimental or non-experimental.
In experimental research, a particular intervention is often used to drive a hypothesized changed in the variables of interest. In non-experimental empirical research, however, the subjects of the study are simply observed without any form of intervention. This is why it’s also referred to as informal research.
How to Identify Empirical Research Articles
Now that you know the types of empirical research as well as methodologies, how do you distinguish an empirical research paper from a regular research paper? Well, as with any other research question, empirical research questions usually have features that can help you identify them as shown below