The Empirical Experimental method will be determined soon after the definition of the Usability  Evaluation type that will be used. 

After that, then a empirical study method has to be chosen:

Controlled Experiment: from the combination of the four previously defined sets of Usability Evaluation Subjects (see Task P1a), the quantitative data typeand the Usability Test method, the study is used as an experimental method. It should be noted that in a Controlled Experiment the qualitative data can also be obtained from open questions.

Survey: If the objective is to obtain quantitative or qualitative data in an online environment, it is suggested to perform a Survey. 

The Survey study will be developed when it is possible to generalize the conclusions. This study can be: 

• Descriptive, when conducted to enable assertions about some population; 

• Exploratory: is about how user certain technique or why some participante prefer one technique while others prefer another and;

• Explorative this objective is used as a pre-study for further investigation, to ensure that important issues have not been forgotten.

Case Study: Nevertheless,if the study is carried out in a natural environment or in a company and the profiles are selected in the set of Usability Evaluation Subjects (Domain Tester, Domain Analyst,  Domain Developer or End User) and the qualitative data, the evaluation will use a Case Study as an Empirical Study Method.

This task is performed when the Process Executor needs select the type of empirical study.

If Usability Evaluation was chosen, then the Process Executor must select Survey, Case Study or Controlled Experiment as an empirical study.

If Heuristic Evaluation was chosen, then the Process Executor must select Survey as an empirical study.