answer
Four main techniques for an exploratory investigation
Document review. ...
Interviews. ...
Surveys (face-to-face or online) ...
Field observation.
Power transformer tests
a) Power factor test. ...
b) Insulation resistance test: It is the resistance (in Megohms) offered by an insulation when a direct current voltage is applied to it for a given time. ...
c) Transformation ratio test. ...
d) Ohmic resistance test to windings.
The Anova requires compliance with the following assumptions:
The populations (probability distributions of the dependent variable corresponding to each factor) are normal.
The K samples on which the treatments are applied are independent.
The populations all have equal variance (homoscedasticity).
Mixed methods (MM) combine the quantitative (quanti) and qualitative (quali) perspective in the same study, with the aim of giving depth to the analysis when the research questions are complex.